Influence of water and terpenes on flammability in some dominant Mediterranean species - Alessio, G A; Penuelas, J; Llusia, J; Ogaya, R; Estiarte, M; De Lillis, M (INTERNATIONAL JOURNAL OF WILDLAND FIRE, 2008)
In the Mediterranean basin, fires are a major concern for forest and shrubland ecosystems. We studied flammability, its seasonality and its relationship with leaf moisture and volatile terpene content and emission in the dominant species of a Mediterranean shrubland and forest in Catalonia ( NE Iberian Peninsula). We measured temperatures and time elapsed between the three flammability phases: smoke, pyrolysis and flame, for four seasons. We sampled twice in spring because of an occasional drought period during this season. Flammability had a significant relationship with leaf hydration, in the shrubland and in the forest. Few and only weak correlations were found between terpene content and flammability. In the future, arid conditions projected by climatic and ecophysiological models will increase fire risk through decreased hydration and subsequent increased flammability of the species.
Keywords: Arbutus unedo; Cistus albidus; emission and content of volatile compounds; Erica multiflora; Globularia alypum; phillyrea latifolia; Pinus halepensis; Pistacia lentiscus; Quercus ilex; Rosmarinus officinalis

Influence of water and terpenes on flammability in some dominant Mediterranean species - Alessio, G. A.; Penuelas, J.; Llusia, J.; Ogaya, R.; Estiarte, M.; De Lillis, M. (INTERNATIONAL JOURNAL OF WILDLAND FIRE, 2008)
In the Mediterranean basin, fires are a major concern for forest and shrubland ecosystems. We studied flammability, its seasonality and its relationship with leaf moisture and volatile terpene content and emission in the dominant species of a Mediterranean shrubland and forest in Catalonia ( NE Iberian Peninsula). We measured temperatures and time elapsed between the three flammability phases: smoke, pyrolysis and flame, for four seasons. We sampled twice in spring because of an occasional drought period during this season. Flammability had a significant relationship with leaf hydration, in the shrubland and in the forest. Few and only weak correlations were found between terpene content and flammability. In the future, arid conditions projected by climatic and ecophysiological models will increase fire risk through decreased hydration and subsequent increased flammability of the species.
The following values have no corresponding Zotero field: pub-location: 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA publisher: CSIRO PUBLISHING
Keywords: Arbutus unedo; Cistus albidus; emission and content of volatile compounds; Erica multiflora; Globularia alypum; phillyrea latifolia; Pinus halepensis; Pistacia lentiscus; Quercus ilex; Rosmarinus officinalis

Influence of water-stress acclimation and Tuber melanosporum mycorrhization on Quercus ilex seedlings - Domínguez Núñez, José Alfonso; Planelles González, Rosa; Rodríguez Barreal, José Antonio; Saiz de Omeñaca González, José Antonio (Agroforestry Systems, 2008)
Mycorrhizal and non-mycorrhizal holm oak (Quercus ilex L.) seedlings inoculated with black trufﬂe (Tuber melanosporum) were grown under nursery conditions and subjected to drought hardening for 4 months in autumn and winter followed by irrigation for 10 days. Leaf water potential and stomatal conductance were monitored during the 4 months of drought. When the test was completed (March), measurements were made for each treatment (inoculated or non-inoculated), and watering regime (watered and water-stressed). Pressure–volume curves, osmotic potential at full turgor, osmotic potential at zero turgor and the tissue modulus of elasticity near full turgor were calculated. Mycorrhizal colonization and growth, and the content of the main mineral nutrients N, P, K, Ca and Mg were measured. Water stress affected plant growth, caused an elastic adjustment of the plant tissues, and decreased the P and K content, and inoculation improved the nitrogen content. Drought acclimation apparently achieved the goal of improving the drought tolerance of holm oak seedlings, without depressing ectomycorrhizal root colonization by T. melanosporum.
Keywords: á mineral nutrition á; black truffle á drought; Black trufﬂe; Drought hardening; Elastic adjustment; elastic adjustment á inoculation; hardening á; Inoculation; Mineral nutrition; Nursery; nursery á osmotic adjustment; osmotic adjustment

Influence of water-stress acclimation and Tuber melanosporum mycorrhization on Quercus ilex seedlings - Domínguez Núñez, José Alfonso; Planelles González, Rosa; Rodríguez Barreal, José Antonio; Saiz de Omeñaca González, José Antonio (Agroforestry Systems, 2008)
Mycorrhizal and non-mycorrhizal holm oak (Quercus ilex L.) seedlings inoculated with black trufﬂe (Tuber melanosporum) were grown under nursery conditions and subjected to drought hardening for 4 months in autumn and winter followed by irrigation for 10 days. Leaf water potential and stomatal conductance were monitored during the 4 months of drought. When the test was completed (March), measurements were made for each treatment (inoculated or non-inoculated), and watering regime (watered and water-stressed). Pressure–volume curves, osmotic potential at full turgor, osmotic potential at zero turgor and the tissue modulus of elasticity near full turgor were calculated. Mycorrhizal colonization and growth, and the content of the main mineral nutrients N, P, K, Ca and Mg were measured. Water stress affected plant growth, caused an elastic adjustment of the plant tissues, and decreased the P and K content, and inoculation improved the nitrogen content. Drought acclimation apparently achieved the goal of improving the drought tolerance of holm oak seedlings, without depressing ectomycorrhizal root colonization by T. melanosporum.
Keywords: á mineral nutrition á; black truffle á drought; Black trufﬂe; Drought hardening; Elastic adjustment; elastic adjustment á inoculation; hardening á; Inoculation; Mineral nutrition; Nursery; nursery á osmotic adjustment; osmotic adjustment

Interactive responses of Quercus suber L. seedlings to light and mild water stress: effects on morphology and gas exchange traits - Puértolas, J; Pardos, M; Jiménez, M D (Annals of Forest Science, 2008)
• The combined eﬀect of water stress and light on seedlings of forest species is a key factor to determine the best silvicultural and aﬀorestation practices in the Mediterranean area. • The aims of this work was (1) to determine the optimal light level for the early development of cork oak seedlings under mild water stress and (2) to test if the combined eﬀect of water stress and light followed the trade-oﬀ, the facilitation or the orthogonal hypothesis. • Shade reduced instantaneous photosynthetic rates and water use eﬃciency in cork oak. However, seedlings grown under moderate shade (15% of full sunlight) were capable to accumulate similar amount of biomass than those grown under more illuminated environments by increasing their speciﬁc leaf area. Absolute diﬀerences in net photosynthesis between light treatments were higher in well watered than in water stressed seedlings. However, the impact of both factors on overall growth was orthogonal. • We concluded that cork oak development is impaired under deep shade (5% of full sunlight) but it can be optimal under moderate shade (15% of full sunlight) even under moderate water stress. Implications of these patterns on regeneration, cultivation and aﬀorestation of cork oak are discussed.
Keywords: Cork oak; foliar anatomy; photosynthesis rate; shade acclimation; water use effciency

Interactive responses of Quercus suber L. seedlings to light and mild water stress: effects on morphology and gas exchange traits - Puértolas, J.; Pardos, M.; Jiménez, M. D. (Annals of Forest Science, 2008)
• The combined eﬀect of water stress and light on seedlings of forest species is a key factor to determine the best silvicultural and aﬀorestation practices in the Mediterranean area. • The aims of this work was (1) to determine the optimal light level for the early development of cork oak seedlings under mild water stress and (2) to test if the combined eﬀect of water stress and light followed the trade-oﬀ, the facilitation or the orthogonal hypothesis. • Shade reduced instantaneous photosynthetic rates and water use eﬃciency in cork oak. However, seedlings grown under moderate shade (15% of full sunlight) were capable to accumulate similar amount of biomass than those grown under more illuminated environments by increasing their speciﬁc leaf area. Absolute diﬀerences in net photosynthesis between light treatments were higher in well watered than in water stressed seedlings. However, the impact of both factors on overall growth was orthogonal. • We concluded that cork oak development is impaired under deep shade (5% of full sunlight) but it can be optimal under moderate shade (15% of full sunlight) even under moderate water stress. Implications of these patterns on regeneration, cultivation and aﬀorestation of cork oak are discussed.
Keywords: Cork oak; foliar anatomy; photosynthesis rate; shade acclimation; water use effciency

Intraspecific competition and water use efficiency in Quercus suber: evidence of an optimum tree density? - Gouveia, António C; Freitas, Helena (Trees, 2008)
The dehesa and montado agroecosystems seem to be water-stress induced structures and some authors have found evidence of a relationship between stand tree density and mean annual precipitation. In order to assess the ecophysiological responses of Quercus suber to increasing tree density and to evaluate if there was evidence of an ‘‘optimum tree density’’ with respect to mean annual rainfall in our study area, we established a tree-density gradient of 20, 40, and 60 trees ha -1 , coded D20, D40, and D60, respectively. Trees in D40 plots had higher speciﬁc leaf area (SLA) values and the highest water content. Both D20 and D60 trees had leaves with higher dry matter content (LDMC). The trade-off between SLA and LDMC was very strong and placed D40 trees as the least stressed, in terms of leaf anatomy. We also found differences in mean carbon isotope discrimination (D), between different density plots, as big as 1.25%. Again, D40 trees discriminated more against 13 C than the trees from D20 and D60 plots, which suggests a less conservative water use strategy, possibly deriving from greater water availability. The lower water retention in the D20 areas and the increased competition for water resources in D60 plots placed trees, in both areas, in a more stressful situation, regarding water availability. The D40 areas thus seemed to represent a more favourable environment for Q. suber in our montado. Therefore, the areas with 40 trees ha -1 suggest the existence of an optimum tree density with respect to annual rainfall in our site, and may represent a compromise between an increased retention of water resources and intraspeciﬁc competition.
Keywords: carbon isotope discrimination; evergreen oak; montado; Specific leaf area; stand density

La renta ambiental de los bosques - CAMPOS PALACIN, P; CAPARROS GASS, A (ARBOR Ciencia, Pensamiento y Cultura, 2008)
The objective of this paper is to show the measurement of the environmental income from two private Spanish forests, the Cork Oak Woodlands of the Alcornocales Natural Park (Cádiz and Málaga) and the Scotch Pine Forest of the Sierra de Guadarrama (Madrid and Segovia). We also contribute to the technical and political debate on governmental regulations of forest environmental accounting in European Union. We have measured the environmental goods and services consumed by private landowners and public visitors through the contingent valuation technique. We have estimated the value of mushrooms gathering by public visitors in the Scotch Pine Forests of the Sierra de Guadarrama taking the price and harvest from the mushroom market in Pinar Grande (Soria). The value for carbon estimated accounts for the avoided damage of the greenhouse effect mitigation due to the sequestration of the atmospheric carbon dioxide. The environmental valuations show that the private environmental profitability rates in the Alcornocales Natural Park and in the Sierra de Guadarrama are 2.13 % and 3.43 %, in relation to their corresponding land market prices. We have estimated that the total net values added are 1.63 and 3.28 times higher than its corresponding conventional net values added in the Alcornocales Natural Park and in the Sierra de Guadarrama.
Keywords: consumer surplus; Cork oak; Exchange value; Hicksian income; joint production; public expenditure; Scotch pine

La renta ambiental de los bosques - Campos Palacín, P.; Caparrós Gass, A. (ARBOR Ciencia, Pensamiento y Cultura, 2008)
The objective of this paper is to show the measurement of the environmental income from two private Spanish forests, the Cork Oak Woodlands of the Alcornocales Natural Park (Cádiz and Málaga) and the Scotch Pine Forest of the Sierra de Guadarrama (Madrid and Segovia). We also contribute to the technical and political debate on governmental regulations of forest environmental accounting in European Union. We have measured the environmental goods and services consumed by private landowners and public visitors through the contingent valuation technique. We have estimated the value of mushrooms gathering by public visitors in the Scotch Pine Forests of the Sierra de Guadarrama taking the price and harvest from the mushroom market in Pinar Grande (Soria). The value for carbon estimated accounts for the avoided damage of the greenhouse effect mitigation due to the sequestration of the atmospheric carbon dioxide. The environmental valuations show that the private environmental profitability rates in the Alcornocales Natural Park and in the Sierra de Guadarrama are 2.13 % and 3.43 %, in relation to their corresponding land market prices. We have estimated that the total net values added are 1.63 and 3.28 times higher than its corresponding conventional net values added in the Alcornocales Natural Park and in the Sierra de Guadarrama.
Keywords: consumer surplus; Cork oak; Exchange value; Hicksian income; joint production; public expenditure; Scotch pine

Land-use changes may explain the recent range expansion of the Black-shouldered Kite Elanus caeruleus in southern Europe - Balbontín, Javier; Negro, Juan José; Sarasola, José Hernán; Ferrero, Juan José; Rivera, Domingo (Ibis, 2008)
Occasional observations of Black-shouldered Kites Elanus caeruleus in Europe date back to the mid-19th century, but it was only recorded as a breeding species in the early 1960s in Portugal and a few years later in neighbouring Spain. This recent colonization, possibly from Africa where the species is abundant, may be due to climate change, land-use changes in southern Europe, or both. As a ﬁrst step to understanding this range expansion process we have developed a habitat selection model using data from the current strongholds of its European distribution. Comparing the proportion of different habitat types around 46 breeding sites and 45 randomly chosen plots, we have found that the area of cultivated parklands known as dehesas in Spain is a strong predictor of the current distribution range of breeding pairs of Black-shouldered Kites. Speciﬁcally, the percentage of dehesas with planted cereal and a low density of trees (i.e. < 7 trees/ha and thus a savannah-like habitat) within the study plots explained 44.6% of the residual deviance in our model. The minimal adequate model classiﬁed 81.3% of breeding sites and random plots correctly. Our results suggest that Black-shouldered Kites may have taken advantage of the gradual increase of cultivated dehesas in the second half of the 20th century to expand its range in Europe. This particular type of dehesa is structurally similar to the African savannahs where the species thrives and may offer a higher density of rodents than traditional dehesas, which primarily contain pastureland for livestock ranching
Keywords: colonization; Dehesa; habitat selection; Land-use change; occurrence models; raptors.

Land-use changes may explain the recent range expansion of the Black-shouldered Kite Elanus caeruleus in southern Europe - Balbontín, Javier; Negro, Juan José; Sarasola, José Hernán; Ferrero, Juan José; Rivera, Domingo (Ibis, 2008)
Occasional observations of Black-shouldered Kites Elanus caeruleus in Europe date back to the mid-19th century, but it was only recorded as a breeding species in the early 1960s in Portugal and a few years later in neighbouring Spain. This recent colonization, possibly from Africa where the species is abundant, may be due to climate change, land-use changes in southern Europe, or both. As a ﬁrst step to understanding this range expansion process we have developed a habitat selection model using data from the current strongholds of its European distribution. Comparing the proportion of different habitat types around 46 breeding sites and 45 randomly chosen plots, we have found that the area of cultivated parklands known as dehesas in Spain is a strong predictor of the current distribution range of breeding pairs of Black-shouldered Kites. Speciﬁcally, the percentage of dehesas with planted cereal and a low density of trees (i.e. < 7 trees/ha and thus a savannah-like habitat) within the study plots explained 44.6% of the residual deviance in our model. The minimal adequate model classiﬁed 81.3% of breeding sites and random plots correctly. Our results suggest that Black-shouldered Kites may have taken advantage of the gradual increase of cultivated dehesas in the second half of the 20th century to expand its range in Europe. This particular type of dehesa is structurally similar to the African savannahs where the species thrives and may offer a higher density of rodents than traditional dehesas, which primarily contain pastureland for livestock ranching
Keywords: colonization; Dehesa; habitat selection; Land-use change; occurrence models; raptors.

The late glacial–Holocene transition as inferred from ostracod and pollen records in the Lago Piccolo di Avigliana (Northern Italy) - Belis, Claudio a.; Finsinger, Walter; Ammann, Brigitta (Palaeogeography, Palaeoclimatology, Palaeoecology, 2008)
Ostracod and pollen records of Lago Piccolo di Avigliana were used for the reconstruction of aquatic and terrestrial palaeoenvironments between 17 and 10 kyr cal BP. A combination of multivariate ordination techniques (PCA and RDA) made it possible to describe ostracod and pollen biostratigraphies and to evaluate whether changes in the aquatic ecosystem were associated with those in the terrestrial environments. Samples and taxa in the ordination plots were grouped into three clusters: a ﬁrst cluster representing herbaceous and shrub pollen taxa (Juniperus, Chenopodiaceae, Gramineae, Artemisia, and Rubiaceae) associated with ostracods typical of oligotrophic and well oxygenated aquatic environments (Cytherissa lacustris), a second cluster containing pollen taxa representing boreal forests (Betula, Pinus sylvestris, and Pinus cembra) associated with ostracod taxa from shallow oligomesotrophic aquatic environments (Candona candida, Darwinula stevensoni), and a third cluster including pollen of thermophilous trees and shrubs (Corylus, Quercus ilex, Fraxinus, Quercus robur-type, and Ulmus) connected to ostracods representing warm mesotrophic aquatic conditions with aquatic vegetation (Cypria ophtalmica, Metacypris cordata). Hypothesis testing with constrained Monte Carlo permutations rejected the null hypothesis that no relationship exists between ostracod and pollen datasets at 2% level of signiﬁcance. As a whole, changes in temperature and precipitation–evaporation balance that inﬂuenced terrestrial vegetation were represented by changes in trophic level and water level in the aquatic environment.
Keywords: Late glacial–Holocene transition; northern Italy; Ordination; Ostracods; pollen

Leaf accumulation of trace elements and polycyclic aromatic hydrocarbons (PAHs) in Quercus ilex L. - De Nicola, F; Maisto, G; Prati, M V; Alfani, a (Environmental pollution (Barking, Essex : 1987), 2008)
Quercus ilex L. leaves were collected four times in one year at six urban sites and one remote area in order to determine trace element and PAH accumulation through concomitant analyses of unwashed and water-washed leaves. Both unwashed and washed leaves showed the highest amounts of trace elements and PAHs in the urban area. Unwashed leaves showed greater differences between urban and remote areas and among the urban sites than washed leaves for trace element and PAH concentrations. Water-washing resulted in a significant (P<0.001) decrease in leaf concentrations of Cr, Cu, Fe, Pb, V and Zn. By contrast, Cd and total PAH concentrations showed no differences between unwashed and washed leaves.
Keywords: Air Pollutants; Air Pollutants: analysis; Aromatic; Aromatic: analysis; Atomic; biomonitoring; cadmium; Cadmium: analysis; chromium; Chromium: analysis; Cities; copper; Copper: analysis; Environmental Monitoring; Environmental Monitoring: methods; Iron; Iron: analysis; Italy; lead; Lead: analysis; PAHs; Plant Leaves; Plant Leaves: chemistry; Polycyclic Hydrocarbons; Quercus; Quercus ilex L.; Spectrophotometry; Trace Elements; Trace Elements: analysis; Unwashed and washed leaves; Vanadium; Vanadium: analysis; Zinc; Zinc: analysis

Leaf accumulation of trace elements and polycyclic aromatic hydrocarbons (PAHs) in Quercus ilex L. - De Nicola, F.; Maisto, G.; Prati, M. V.; Alfani, A. (Environmental pollution (Barking, Essex : 1987), 2008)
Quercus ilex L. leaves were collected four times in one year at six urban sites and one remote area in order to determine trace element and PAH accumulation through concomitant analyses of unwashed and water-washed leaves. Both unwashed and washed leaves showed the highest amounts of trace elements and PAHs in the urban area. Unwashed leaves showed greater differences between urban and remote areas and among the urban sites than washed leaves for trace element and PAH concentrations. Water-washing resulted in a significant (P<0.001) decrease in leaf concentrations of Cr, Cu, Fe, Pb, V and Zn. By contrast, Cd and total PAH concentrations showed no differences between unwashed and washed leaves.
The following values have no corresponding Zotero field: accession-num: 17892907
Keywords: Air Pollutants; Air Pollutants: analysis; Aromatic; Aromatic: analysis; Atomic; biomonitoring; cadmium; Cadmium: analysis; chromium; Chromium: analysis; Cities; copper; Copper: analysis; Environmental Monitoring; Environmental Monitoring: methods; Iron; Iron: analysis; Italy; lead; Lead: analysis; PAHs; Plant Leaves; Plant Leaves: chemistry; Polycyclic Hydrocarbons; Quercus; Quercus ilex L.; Spectrophotometry; Trace Elements; Trace Elements: analysis; Unwashed and washed leaves; Vanadium; Vanadium: analysis; Zinc; Zinc: analysis

Leaf flavonoid content in Quercus ilex L. resprouts and its seasonal variation - Brossa, R.; Casals, I.; Pintó-Marijuan, M.; Fleck, I. (Trees, 2008)
Here, we provide the ﬁrst report on ﬂavonoid content in holm oak (Quercus ilex L.) leaves, analyzed by HPLC–MS/MS. Flavanols and ﬂavonols were the predominant groups, although proanthocyanidins and many soluble tannins had a relevant presence in all leaf samples. Seasonal variation of ﬂavonoids was determined in extracts from Q. ilex leaves during resprouting after a forest ﬁre in two Mediterranean forests. Similar seasonal trends were observed over 2 years during the two main stress seasons (winter and summer). The most abundant ﬂavonoid was the ﬂavanol epicatechin, which showed similar values during the two seasons. Hexosides of the ﬂavonols, quercetin, kaempferol and rhamnetin showed considerably higher content in winter, especially at the lowest temperatures. These variations in both forests are discussed on the basis of the chlorophyll ﬂuorescence results obtained. Anthocyanins were found practically absent in mature leaves. Nutrient or water availability differences between sites or seasons were not related to changes in leaf ﬂavonolhexoside content.
Keywords: á; á hplc; chlorophyll fluorescence; chlorophyll fluorescence á flavanols; esi; flavanols; flavonol-hexosides; flavonol-hexosides á holm oak; Holm oak; HPLC–ESI–MS/MS; ms

Leaf flavonoid content in Quercus ilex L. resprouts and its seasonal variation - Brossa, R.; Casals, I.; Pintó-Marijuan, M.; Fleck, I. (Trees, 2008)
Here, we provide the ﬁrst report on ﬂavonoid content in holm oak (Quercus ilex L.) leaves, analyzed by HPLC–MS/MS. Flavanols and ﬂavonols were the predominant groups, although proanthocyanidins and many soluble tannins had a relevant presence in all leaf samples. Seasonal variation of ﬂavonoids was determined in extracts from Q. ilex leaves during resprouting after a forest ﬁre in two Mediterranean forests. Similar seasonal trends were observed over 2 years during the two main stress seasons (winter and summer). The most abundant ﬂavonoid was the ﬂavanol epicatechin, which showed similar values during the two seasons. Hexosides of the ﬂavonols, quercetin, kaempferol and rhamnetin showed considerably higher content in winter, especially at the lowest temperatures. These variations in both forests are discussed on the basis of the chlorophyll ﬂuorescence results obtained. Anthocyanins were found practically absent in mature leaves. Nutrient or water availability differences between sites or seasons were not related to changes in leaf ﬂavonolhexoside content.
Keywords: á; á hplc; chlorophyll fluorescence; chlorophyll fluorescence á flavanols; esi; flavanols; flavonol-hexosides; flavonol-hexosides á holm oak; Holm oak; HPLC–ESI–MS/MS; ms

Life-history traits in an evergreen Mediterranean oak respond differentially to previous experimental environments - Benayas, J M R; Cuesta, Bárbara; VILLAR-SALVADOR, P; Jáuregui, Pedro (Web Ecology, 2008)
Living organisms respond both to current and previous environments, which can have important consequences on population dynamics. However, there is little experimental evidence based on long-term field studies of the effects of previous environments on the performance of individuals. We tested the hypothesis that trees that establish under different environmental conditions perform differently under similar post-establishment conditions. We used the slow-growing, evergreen Mediterranean oak Quercus ilex subsp. rotundifolia as target species. We analyzed the effects of previous environments, competition effects and tradeoffs among life-history traits (survival, growth, and reproduction). We enhanced seedling establishment for three years by reducing abiotic environmental harshness by means of summer irrigation and artificial shading in 12 experimental plots, while four plots remained as controls. Then these treatments were interrupted for ten years. Seedlings under ameliorated environmental conditions survived and grew faster during early establishment. During the post-management period, previous treatments 1) did not have any effect on survival, 2) experienced a slower above-ground growth, 3) decreased root biomass as indicated from reflectivity of Ground Penetration Radar, 4) increased acorn production mostly through a greater canopy volume and 5) increased acorn production effort. The trees exhibited a combination of effects related to acclimation for coping with abiotic stress and effects of intra-specific competition. In accordance with our hypothesis, tree performance overall depended on previous environmental conditions, and the response was different for different life-history traits. We recommend early management because it increased plot cover, shortened the time to attain sexual maturity and increased the amount of acorn production. Plots such as those assessed in this study may act as sources of propagules in deforested agricultural landscapes thus aiding natural establishment of new plants
Keywords: acorn production; canopy volume; competition; environmental conditions; Growth; management (voyant); shoot/root ratio

Life-history traits in an evergreen Mediterranean oak respond differentially to previous experimental environments - Benayas, J. M. R.; Cuesta, Bárbara; Villar-Salvador, P.; Jáuregui, Pedro (Web Ecology, 2008)
Living organisms respond both to current and previous environments, which can have important consequences on population dynamics. However, there is little experimental evidence based on long-term field studies of the effects of previous environments on the performance of individuals. We tested the hypothesis that trees that establish under different environmental conditions perform differently under similar post-establishment conditions. We used the slow-growing, evergreen Mediterranean oak Quercus ilex subsp. rotundifolia as target species. We analyzed the effects of previous environments, competition effects and tradeoffs among life-history traits (survival, growth, and reproduction). We enhanced seedling establishment for three years by reducing abiotic environmental harshness by means of summer irrigation and artificial shading in 12 experimental plots, while four plots remained as controls. Then these treatments were interrupted for ten years. Seedlings under ameliorated environmental conditions survived and grew faster during early establishment. During the post-management period, previous treatments 1) did not have any effect on survival, 2) experienced a slower above-ground growth, 3) decreased root biomass as indicated from reflectivity of Ground Penetration Radar, 4) increased acorn production mostly through a greater canopy volume and 5) increased acorn production effort. The trees exhibited a combination of effects related to acclimation for coping with abiotic stress and effects of intra-specific competition. In accordance with our hypothesis, tree performance overall depended on previous environmental conditions, and the response was different for different life-history traits. We recommend early management because it increased plot cover, shortened the time to attain sexual maturity and increased the amount of acorn production. Plots such as those assessed in this study may act as sources of propagules in deforested agricultural landscapes thus aiding natural establishment of new plants
Keywords: acorn production; canopy volume; competition; environmental conditions; Growth; management (voyant); shoot/root ratio

Light distribution in scattered-trees open woodlands in Western Spain - Montero, María Jesús; Moreno, Gerardo; Bertomeu, Manuel (Agroforestry Systems, 2008)
We have studied the percentage of radiation transmitted through the tree canopy to the underlying pasture and crops in dehesas of Southwest Spain by means of ﬁsh-eye photographs taken at different distances from the tree. Thirty-six trees were studied covering all the diametric classes (0.1–14 m canopy width) of two stands, with mean density of 19 mature trees ha -1 . Intercepted light decreased with distance following an logistic curve, indicating a rapid increase in the light availability with distance from the tree. For mature trees, radiation was constant beyond 20 m. Applying a multivariable regression light equation, distance, stem diameter and canopy width explained more than 88% of the light variability for each orientation studied. A simple model was built up from light equations, tree growth curves and allometric relationships. From this model, we have estimated that radiation available for crops and pasture decreased up to 21% due to the presence of trees in a standard dehesa with 24 mature trees ha -1 and 13% of canopy cover. In addition, we have generated different radiation maps of virtual dehesas differing in tree age, density and arrangement, which could be useful to determine optimal tree planting schemes and consequent pruning and thinning regimes.
Keywords: allometric relationships; Dehesa; fish-eye photograph; light transmittance; Quercus ilex; radiation map

Light distribution in scattered-trees open woodlands in Western Spain - Montero, María Jesús; Moreno, Gerardo; Bertomeu, Manuel (Agroforestry Systems, 2008)
We have studied the percentage of radiation transmitted through the tree canopy to the underlying pasture and crops in dehesas of Southwest Spain by means of ﬁsh-eye photographs taken at different distances from the tree. Thirty-six trees were studied covering all the diametric classes (0.1–14 m canopy width) of two stands, with mean density of 19 mature trees ha -1 . Intercepted light decreased with distance following an logistic curve, indicating a rapid increase in the light availability with distance from the tree. For mature trees, radiation was constant beyond 20 m. Applying a multivariable regression light equation, distance, stem diameter and canopy width explained more than 88% of the light variability for each orientation studied. A simple model was built up from light equations, tree growth curves and allometric relationships. From this model, we have estimated that radiation available for crops and pasture decreased up to 21% due to the presence of trees in a standard dehesa with 24 mature trees ha -1 and 13% of canopy cover. In addition, we have generated different radiation maps of virtual dehesas differing in tree age, density and arrangement, which could be useful to determine optimal tree planting schemes and consequent pruning and thinning regimes.
Keywords: allometric relationships; Dehesa; fish-eye photograph; light transmittance; Quercus ilex; radiation map

Long-term monitoring of metal pollution by urban trees - Gratani, Loretta; Crescente, Maria Fiore; Varone, Laura (Atmospheric Environment, 2008)
The atmospheric pollution level in Rome was monitored in the year 2006. Five sites in the historical centre were considered. The concentration of Al, Fe, Cu, Zn, and Pb was analysed in washed and unwashed Quercus ilex leaf samples. Moreover, in order to verify the changes in atmospheric pollution in the historical centre of the city after the introduction of the limited trafﬁc zone (LTZ), previous data collected in the years 1979 and 1996 were also considered. The leaf’s internal concentration of Al, Fe, Cu, Zn, and Pb was 28, 22, 40, 77 and 37%, respectively, of the total concentration, and it was in the same range monitored in the years 1979 and 1996. The results underlined a signiﬁcant (p < 0.05) decreasing of metal concentration on unwashed leaves with on an average 92%, compared to ones monitored in the year 1979. The mean value of the total trafﬁc ﬂow during the limitated period (Monday to Friday, from 6:30 a.m. to 6:00 p.m, and Saturday from 2:00 to 6:00 p.m.) was 75.000 vehicles, compared to 90.000 ones before the electronic gates were activated; moreover, a 15% decrease in the daily trafﬁc peak (8:30–9:30 a.m) was monitored. The metal concentration in Q. ilex leaves was be related to motor vehicle emissions, conﬁrmed also by PCA. The data obtained on the leaf metal concentration trend in Rome, over a period of 27 years, underlined the importance of the City Council provisions. These results conﬁrmed the use of Q. ilex for long-term monitoring of metal concentration in those urban areas where the species was naturally present, and widely distributed in the landscape.
Keywords: Bio-monitor; Metal pollution; Quercus ilex; rome; Vehicular trafﬁc

Man-Made Landscapes From the Third–Second Millennia Bc: the Example of Castelo Velho (Freixo De Numão, North-East Portugal) - Figueiral, Isabel; Jorge, Susana O (Oxford Journal of Archaeology, 2008)
The analysis of charred plant material from Castelo Velho (northeastern Portugal) yields information about the environmental background of a long-term architectural project. Work focuses on the physical characteristics of this sui generis site and on the interrelationships between human communities and their vegetal environment. Important vegetation changes are recorded despite the fact that site ‘occupation’is considered to be sporadic and therefore causing only minor anthropogenic impact. Evergreen oaks (Quercus, evergreen) dominate during the ﬁrst two stratigraphic layers but are replaced by the tree-strawberry (Arbutus unedo) during a third layer. This change may result from a premeditated woodland management, ensuring that the site remained visible in the distance. Special attention is given to the plant assemblage and broken pottery found in a sealed structure (layer 3) and thought to have served a ‘ritual’ purpose. Seeds of Triticum aestivum/ compactum are largely predominant.
Keywords: Arbutus unedo (voyant); CHARCOAL ANALYSIS; Evergreen oaks; vegetation changes

Man-Made Landscapes From the Third–Second Millennia Bc: the Example of Castelo Velho (Freixo De Numão, North-East Portugal) - Figueiral, Isabel; Jorge, Susana O. (Oxford Journal of Archaeology, 2008)
The analysis of charred plant material from Castelo Velho (northeastern Portugal) yields information about the environmental background of a long-term architectural project. Work focuses on the physical characteristics of this sui generis site and on the interrelationships between human communities and their vegetal environment. Important vegetation changes are recorded despite the fact that site ‘occupation’is considered to be sporadic and therefore causing only minor anthropogenic impact. Evergreen oaks (Quercus, evergreen) dominate during the ﬁrst two stratigraphic layers but are replaced by the tree-strawberry (Arbutus unedo) during a third layer. This change may result from a premeditated woodland management, ensuring that the site remained visible in the distance. Special attention is given to the plant assemblage and broken pottery found in a sealed structure (layer 3) and thought to have served a ‘ritual’ purpose. Seeds of Triticum aestivum/ compactum are largely predominant.
Keywords: Arbutus unedo (voyant); CHARCOAL ANALYSIS; Evergreen oaks; vegetation changes

Masting mediated by summer drought reduces acorn predation in mediterranean oak forests - Espelta, Josep Maria; Cortés, Pilar; Molowny-Horas, Roberto; Sánchez-Humanes, Belén; Retana, Javier (ECOLOGY, 2008)
Temporally variable production of seed crops by perennial plants (masting) has been hypothesized to be a valuable mechanism in the reduction of seed predation by satiating and starving seed consumers. To achieve these benefits, coexisting species subjected to the same predator would benefit from a similar pattern of seeding fluctuation over time that could lead to a reduction in predation at the within-species level. We tested for the existence of an environmental factor enforcing synchrony in acorn production in two sympatric Mediterranean oaks ( Quercus ilex and Q. humilis) and the consequences on within-species and between species acorn predation, by monitoring 15 mixed forests (450 trees) over seven years. Acorn production in Q. ilex and Q. humilis was highly variable among years, with high population variability (CVp) values. The two species exhibited a very different pattern across years in their initial acorn crop size ( sum of aborted, depredated, and sound acorns). Nevertheless, interannual differences in summer water stress modified the likelihood of abortion during acorn ripening and enforced within-and, particularly, between-species synchrony and population variability in acorn production. The increase in CVp from initial to mature acorn crop ( after summer) accounted for 33% in Q. ilex, 59% in Q. humilis, and 60% in the two species together. Mean yearly acorn pre-dispersal predation by invertebrates was considerably higher in Q. humilis than in Q. ilex. Satiation and starvation of predators was recorded for the two oaks, and this effect was increased by the year-to-year variability in the size of the acorn crop of the two species combined. Moreover, at a longer time scale ( over seven years), we observed a significant reduction in the mean proportion of acorns depredated for each oak and the variability in both species' acorn production combined. Therefore, our results demonstrate that similar patterns of seeding fluctuation over time in coexisting species mediated by an environmental cue ( summer drought) may contribute to the reduction of the impact of seed predation at a within-species level. Future research should be aimed at addressing whether this process could be a factor assisting in the coexistence of Q. ilex and Q. humilis.
The following values have no corresponding Zotero field: pub-location: 1990 M STREET NW, STE 700, WASHINGTON, DC 20036 USA publisher: ECOLOGICAL SOC AMER
Keywords: Curculio spp.; fruit abortion; fruiting synchrony; Mediterranean mixed-oak forests; oaks; predator satiation; Quercus humilis; Quercus ilex; resource matching

Masting mediated by summer drought reduces acorn predation in mediterranean oak forests - Espelta, Josep Maria; Cortés, Pilar; Molowny-Horas, Roberto; Sánchez-Humanes, Belén; Retana, Javier (ECOLOGY, 2008)
Temporally variable production of seed crops by perennial plants (masting) has been hypothesized to be a valuable mechanism in the reduction of seed predation by satiating and starving seed consumers. To achieve these benefits, coexisting species subjected to the same predator would benefit from a similar pattern of seeding fluctuation over time that could lead to a reduction in predation at the within-species level. We tested for the existence of an environmental factor enforcing synchrony in acorn production in two sympatric Mediterranean oaks ( Quercus ilex and Q. humilis) and the consequences on within-species and between species acorn predation, by monitoring 15 mixed forests (450 trees) over seven years. Acorn production in Q. ilex and Q. humilis was highly variable among years, with high population variability (CVp) values. The two species exhibited a very different pattern across years in their initial acorn crop size ( sum of aborted, depredated, and sound acorns). Nevertheless, interannual differences in summer water stress modified the likelihood of abortion during acorn ripening and enforced within-and, particularly, between-species synchrony and population variability in acorn production. The increase in CVp from initial to mature acorn crop ( after summer) accounted for 33% in Q. ilex, 59% in Q. humilis, and 60% in the two species together. Mean yearly acorn pre-dispersal predation by invertebrates was considerably higher in Q. humilis than in Q. ilex. Satiation and starvation of predators was recorded for the two oaks, and this effect was increased by the year-to-year variability in the size of the acorn crop of the two species combined. Moreover, at a longer time scale ( over seven years), we observed a significant reduction in the mean proportion of acorns depredated for each oak and the variability in both species' acorn production combined. Therefore, our results demonstrate that similar patterns of seeding fluctuation over time in coexisting species mediated by an environmental cue ( summer drought) may contribute to the reduction of the impact of seed predation at a within-species level. Future research should be aimed at addressing whether this process could be a factor assisting in the coexistence of Q. ilex and Q. humilis.
Keywords: Curculio spp.; fruit abortion; fruiting synchrony; Mediterranean mixed-oak forests; oaks; predator satiation; Quercus humilis; Quercus ilex; resource matching

Materia orgánica de suelos bajo encinas. Mineralización de carbono y nitrógeno - Gonzalez Parra, J; Candás Villar, M A (Forest Systems, 2008)
Soil characteristics under evergreen oaks forest (Quercus rotundifolia Lam.) located at the East of Segovia were studied. The soils were formed from gneis and limestone. The whole soil was 0-20 cm depth. The soils were classified as mollic Leptosols, eutric Cambisols and calcaric Cambisols. Horizons sequences were the following: O, Ah1, Ah2, C and O, Ah1, Ah2, BC. Organic horizons (3-0 cm depth) were formed by the not-yet decomposed organic remains from evergreen oaks. Mean organic matter content was 25%. The C:N ratio was high and free organic carbon was near 90% of the total carbon, which correspond with a low degree of humification. Soil texture was loamy sand and sandy loam. Soils on limestone present the highest clay fraction contents. The bases saturation degree was high, being Ca 2+ the fundamental cation of exchange complex. Organic matter content and C:N ratio were lower in organic minerals horizons than in organic horizons. Humification degree was 60% with a predominance of HAs over FAs. The polimerization of humic substances makes possible the formation of humus «moder». Carbon mineralization to the total C was ten times higher than nitrogen mineralization in upper horizons. In all horizons the nitrification was higher than N mineralization. Carbon mineralization was lower and N mineralization was higher in deeper horizons compearing with upper horizons.
Keywords: mineralization; nitrogen; organic matter; Quercus rotundifolia; soils

Medicinal plants in the Mediterranean area: synthesis of the results of the project Rubia. - González-Tejero, M R; Casares-Porcel, M; Sánchez-Rojas, C P; Ramiro-Gutiérrez, J M; Molero-Mesa, J; Pieroni, A; Giusti, M E; Censorii, E; de Pasquale, C; Della, a; Paraskeva-Hadijchambi, D; Hadjichambis, a; et al. (Journal of ethnopharmacology, 2008)
Within the scope of the European project RUBIA (ICA3-2002-10023), research has been performed on the traditional use and handling of plant species in several Mediterranean countries, Albania, Algeria, Cyprus, Egypt, Italy, Morocco, and Spain. This paper synthesises the chief results related to the medicinal utilization of those plants.
Keywords: Ethnobotany; Medicinal; Medicinal plants; Mediterranean; Mediterranean Region; Plants; Species Specificity

Microbial activity and quality changes during decomposition of Quercus ilex leaf litter in three Mediterranean woods - Papa, S.; Pellegrino, A.; Fioretto, A. (Applied Soil Ecology, 2008)
Changes in enzyme activities during litter decomposition provide diagnostic information on the dynamics of decay and functional microbial succession. Here we report a comparative study of enzyme activities involved in the breakdown of major plant components and of other key parameters (microbial respiration, fungal biomass, N, lignin and cellulose contents) in homogeneous leaf litter of Quercus ilex L. incubated in three evergreen oak woods in Southern Italy (Campania), differing for chemical and physical soil characteristics and microclimatic conditions. The results showed that the litter mass loss rates were similar in the three wood sites. Independently of the incubation sites, cellulase, xylanase and peroxydase activities showed seasonal variations with maximum and minimum levels in wet and dry periods, respectively, and this pattern closely matched microbial respiration. Activities of a- and b-amylase, instead, were high at the beginning of incubation and quickly decreased with decomposition progress because their substrate was rapidly depleted. Laccase activity, in contrast, was low at the beginning of incubation but after 6 months it increased signiﬁcantly. The increase of laccase activity was correlated to an increase in fungal biomass, probably reﬂecting a major shift in the litter microbial community. As concerns quality changes, N and lignin content did not signiﬁcantly change during decay. The cellulosic component started being degraded after about 6 months in the litter incubated in two of the three wood sites and from the start of decomposition in the third site. Apart from minor differences in the levels of certain enzyme activities, the data showed that the functional microbial succession involved in the decomposition of Q. ilex leaf litter did not change appreciably in response to differences in soil and microclimatic conditions in the incubation sites.
Keywords: Cellulose; Enzyme activities; Fungal biomass; Lignin; litter decomposition; Microbial respiration

Microbial activity and quality changes during decomposition of Quercus ilex leaf litter in three Mediterranean woods - Papa, S; Pellegrino, a; Fioretto, a (Applied Soil Ecology, 2008)
Changes in enzyme activities during litter decomposition provide diagnostic information on the dynamics of decay and functional microbial succession. Here we report a comparative study of enzyme activities involved in the breakdown of major plant components and of other key parameters (microbial respiration, fungal biomass, N, lignin and cellulose contents) in homogeneous leaf litter of Quercus ilex L. incubated in three evergreen oak woods in Southern Italy (Campania), differing for chemical and physical soil characteristics and microclimatic conditions. The results showed that the litter mass loss rates were similar in the three wood sites. Independently of the incubation sites, cellulase, xylanase and peroxydase activities showed seasonal variations with maximum and minimum levels in wet and dry periods, respectively, and this pattern closely matched microbial respiration. Activities of a- and b-amylase, instead, were high at the beginning of incubation and quickly decreased with decomposition progress because their substrate was rapidly depleted. Laccase activity, in contrast, was low at the beginning of incubation but after 6 months it increased signiﬁcantly. The increase of laccase activity was correlated to an increase in fungal biomass, probably reﬂecting a major shift in the litter microbial community. As concerns quality changes, N and lignin content did not signiﬁcantly change during decay. The cellulosic component started being degraded after about 6 months in the litter incubated in two of the three wood sites and from the start of decomposition in the third site. Apart from minor differences in the levels of certain enzyme activities, the data showed that the functional microbial succession involved in the decomposition of Q. ilex leaf litter did not change appreciably in response to differences in soil and microclimatic conditions in the incubation sites.
Keywords: Cellulose; Enzyme activities; Fungal biomass; Lignin; litter decomposition; Microbial respiration

Modeling volatile isoprenoid emissions – a story with split ends - Grote, R; Niinemets, Ü (Plant Biology, 2008)
Accurate prediction of plant-generated volatile isoprenoid fluxes is necessary for reliable estimation of atmospheric ozone and aerosol formation potentials. In recent years, significant progress has been made in understanding the environmental and physiological controls on isoprenoid emission and in scaling these emissions to canopy and landscape levels. We summarize recent developments and compare different approaches for simulating volatile isoprenoid emission and scaling up to whole forest canopies with complex architecture. We show that the current developments in modeling volatile isoprenoid emissions are “split-ended” with simultaneous but separated efforts in fine-tuning the empirical emission algorithms and in constructing process-based models. In modeling volatile isoprenoid emissions, simplified leaf-level emission algorithms (Guenther algorithms) are highly successful, particularly after scaling these models up to whole regions, where the influences of different ecosystem types, ontogenetic stages, and variations in environmental conditions on emission rates and dynamics partly cancel out. However, recent experimental evidence indicates important environmental effects yet unconsidered and emphasize, the importance of a highly dynamic plant acclimation in space and time. This suggests that current parameterizations are unlikely to hold in a globally changing and dynamic environment. Therefore, long-term predictions using empirical algorithms are not necessarily reliable. We show that process-based models have large potential to capture the influence of changing environmental conditions, in particular if the leaf models are linked with physiologically based whole-plant models. This combination is also promising in considering the possible feedback impacts of emissions on plant physiological status such as mitigation of thermal and oxidative stresses by volatile isoprenoids. It might be further worth while to incorporate main features of these approaches in regional empirically-based emission estimations thereby merging the “split ends”.
Keywords: BVOC emission; Isoprenoids; Modeling; Scaling; Spatial variability; temporal variability

Modelling leaf mass per area in forest canopy as affected by prevailing radiation conditions - Davi, H.; Barbaroux, C.; Dufrêne, E.; François, C.; Montpied, P.; Bréda, N.; Badeck, F. (Ecological Modelling, 2008)
Leaf mass per area (LMA) is a key leaf trait, which conditions the assessment of carbon balance and the adaptation of the species to their environment. LMA decreases exponentially within the canopy at a lower rate coefﬁcient (kLMA) than the extinction coefﬁcient (kPAR) of photosynthetically active radiation (PAR); consequently the canopy is not fully optimized for the carbon balance. A new algorithm to simulate LMA in forest canopies is developed. The algorithm is based on a relationship between LMA of leaves at a given canopy depth and PAR, that they absorb, during leaf growth. The LMA sub-model is then tested against independent experimental data to demonstrate its validity to assess (i) the LMA vertical distribution inside the canopy, (ii) its evolution during the season and (iii) the variability observed between sites, years and species. Then, the LMA sub-model is coupled with a process-based model simulating carbon, water and energy balances in forest ecosystem. The coupled model is applied to a sensitive analysis for a case study in a beech forest.
Keywords: Carbon; Fagus sylvatica L.; Leaf mass per area; Modelling; Photosynthetically active radiation; Quercus ilex L.; Quercus petraea (Matt.) Liebl.

Modelling leaf mass per area in forest canopy as affected by prevailing radiation conditions - Davi, H.; Barbaroux, C.; Dufrêne, E.; François, C.; Montpied, P.; Bréda, N.; Badeck, F. (Ecological Modelling, 2008)
Leaf mass per area (LMA) is a key leaf trait, which conditions the assessment of carbon balance and the adaptation of the species to their environment. LMA decreases exponentially within the canopy at a lower rate coefﬁcient (kLMA) than the extinction coefﬁcient (kPAR) of photosynthetically active radiation (PAR); consequently the canopy is not fully optimized for the carbon balance. A new algorithm to simulate LMA in forest canopies is developed. The algorithm is based on a relationship between LMA of leaves at a given canopy depth and PAR, that they absorb, during leaf growth. The LMA sub-model is then tested against independent experimental data to demonstrate its validity to assess (i) the LMA vertical distribution inside the canopy, (ii) its evolution during the season and (iii) the variability observed between sites, years and species. Then, the LMA sub-model is coupled with a process-based model simulating carbon, water and energy balances in forest ecosystem. The coupled model is applied to a sensitive analysis for a case study in a beech forest.
Keywords: Carbon; Fagus sylvatica L.; Leaf mass per area; Modelling; Photosynthetically active radiation; Quercus ilex L.; Quercus petraea (Matt.) Liebl.

Modelling rainfall interception in a mediterranean Quercus ilex ecosystem: Lesson from a throughfall exclusion experiment - Limousin, Jean-Marc; Rambal, Serge; OURCIVAL, JEAN-MARC; Joffre, Richard (Journal of Hydrology, 2008)
In the Mediterranean basin, precipitation is expected to decline by the end of the 21st century as a consequence of climate change. A throughfall exclusion experiment has been established in a Quercus ilex coppice in southern France to anticipate the response of this ecosystem to a reduced precipitation amount by removing part of the throughfall. The experiment involved four 140 m 2 plots: a control plot, a throughfall exclusion plot, a thinned plot and a throughfall exclusion in a thinned plot. This experiment has been used during nearly two years to monitor throughfall amounts in the different plots. Additionally, stemﬂow has been recorded on 20 trees between 25 April 2006 and 15 May 2007. The control plot had a stem density of 6885 stems ha 1 and a leaf area index of 3.1, rainfall partitioning into interception loss, throughfall and stemﬂow was, respectively, 30.9%, 56.6% and 12.5% of the total precipitation (1605 mm over the study period). Thinning reduced the stem basal area by 33% and the total interception loss by 34.6%. Given the rainfall partitioning, the throughfall exclusion was found to remove 19% of total precipitation, which was conﬁrmed by soil water content measurements. The revised Gash analytical model predicted interception with an agreement of 6.2% of total precipitation. Results show a good transferability of the model to a plot with a different stem density, thus supporting the idea that model parameters and evaporation from a wet canopy scale linearly with canopy cover.
Keywords: Gash analytical model; Mediterranean evergreen forest; Quercus ilex; rainfall interception; throughfall; Throughfall exclusion experiment

Modulation of leaf attributes and water use efficiency in Quercus suber along a rainfall gradient - Gouveia, António C.; Freitas, Helena (Trees, 2008)
The aim of our study was to assess the intraspeciﬁc variation of a range of leaf attributes and carbon isotope discrimination (D), in Quercus suber, along an 800 mm rainfall gradient in Portugal. We measured speciﬁc leaf area (SLA), leaf thickness (LT) and density, and used leaf carbon isotope content as an integrated record of water use efﬁciency. The values of SLA of Q. suber were strongly, positively correlated with rainfall, decreasing as rainfall decreased. This reduction was mainly driven by LT, which was tightly correlated with SLA (R = -0.80, P\0.001), and steadily increased with declining rainfall. The signiﬁcant increase in carbon isotope discrimination towards the wetter end of the gradient, with a difference of 4.2% in D between the two extremes, suggests a strong adjustment of leaf gas exchange to water availability. Leaf changes associated with precipitation in Q. suber thus seem to inﬂuence water economy, since reduction of SLA with the increase of LT with aridity improves water use efﬁ- ciency. These data suggest that this evergreen tree species relies on its foliage plasticity and physiology to overcome water shortage.
Keywords: carbon isotope discrimination; carbon isotope discrimination á; evergreen tree; evergreen tree á; leaf plasticity; leaf plasticity á; rainfall gradient

Modulation of leaf attributes and water use efficiency in Quercus suber along a rainfall gradient - Gouveia, António C.; Freitas, Helena (Trees, 2008)
The aim of our study was to assess the intraspeciﬁc variation of a range of leaf attributes and carbon isotope discrimination (D), in Quercus suber, along an 800 mm rainfall gradient in Portugal. We measured speciﬁc leaf area (SLA), leaf thickness (LT) and density, and used leaf carbon isotope content as an integrated record of water use efﬁciency. The values of SLA of Q. suber were strongly, positively correlated with rainfall, decreasing as rainfall decreased. This reduction was mainly driven by LT, which was tightly correlated with SLA (R = -0.80, P\0.001), and steadily increased with declining rainfall. The signiﬁcant increase in carbon isotope discrimination towards the wetter end of the gradient, with a difference of 4.2% in D between the two extremes, suggests a strong adjustment of leaf gas exchange to water availability. Leaf changes associated with precipitation in Q. suber thus seem to inﬂuence water economy, since reduction of SLA with the increase of LT with aridity improves water use efﬁ- ciency. These data suggest that this evergreen tree species relies on its foliage plasticity and physiology to overcome water shortage.
Keywords: carbon isotope discrimination; carbon isotope discrimination á; evergreen tree; evergreen tree á; leaf plasticity; leaf plasticity á; rainfall gradient

Morphological-anatomical characterization and identification of Tomentella ectomycorrhizas. - Jakucs, Erzsébet; Eros-Honti, Zsolt (Mycorrhiza, 2008)
Over the last two decades, much information has been gathered on the ectomycorrhizal fungus community composition of plant associations of boreal, temperate, and tropical regions. Worldwide, Tomentella ectomycorrhizas (ECM) are often common and dominant in the mycorrhizosphere of coniferous and deciduous forests. They are present under different environmental conditions and associate with diverse plant hosts. Tomentella sporocarps, however, are rarely found aboveground, so Tomentella species are often missing from fungus community studies based on fruit-body presence. Tomentella is a resupinate genus of Thelephoraceae (Basidiomycota) forming black-brown, brown, yellow, or ochre ECM on the roots of gymnosperm and angiosperm trees, distinguished by typical morphological-anatomical characteristics (clamped hyphae, angular mantle, surface network, special rhizomorphs and cystidia). In this paper, we review the taxonomic position and morphological-anatomical characteristics of Tomentella ECM. A short summary of the microscopic features used for distinguishing tomentelloids during morphotyping and identification is presented in order to support molecular and ecological studies of ectomycorrhizal fungus communities.
Keywords: Anatomy; ECM; ectomycorrhiza; identification; morphology; Tomentella

Mycelial abundance and other factors related to truffle productivity in Tuber melanosporum–Quercus ilex orchards - Suz, Laura M.; Martín, María P.; Oliach, Daniel; Fischer, Christine R.; Colinas, Carlos (FEMS Microbiology Letters, 2008)
Relative quantification of DNA from Tuber melanosporum mycelia was performed by conventional and real-time PCR in soil from trees in three truffle orchards of different ages to determine: (1) whether burn appearance is related to the amount of T. melanosporum mycelium in soil, and (2) whether productivity onset and truffle production are related to (a) the amount of T. melanosporum mycelium in soil, (b) tree height and diameter, (c) burn extension and (d) surface rock cover. The burn seems to appear only after a certain amount of mycelium has formed. Precociously productive trees presented higher quantities of mycelium than nonproductive trees in the productivity onset study, while highly productive trees presented less quantities of mycelium than nonproductive trees in the productivity study. Trees with high but not excessive surface rock cover showed greater truffle production. Larger trees tended to display a burn earlier than smaller trees.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: burn; DNA soil mycelium; real-time PCR; rock cover; truffle; Tuber melanosporum

Mycelial abundance and other factors related to truffle productivity in Tuber melanosporum–Quercus ilex orchards - Suz, Laura M; Martín, María P; Oliach, Daniel; Fischer, Christine R; Colinas, Carlos (FEMS Microbiology Letters, 2008)
Relative quantification of DNA from Tuber melanosporum mycelia was performed by conventional and real-time PCR in soil from trees in three truffle orchards of different ages to determine: (1) whether burn appearance is related to the amount of T. melanosporum mycelium in soil, and (2) whether productivity onset and truffle production are related to (a) the amount of T. melanosporum mycelium in soil, (b) tree height and diameter, (c) burn extension and (d) surface rock cover. The burn seems to appear only after a certain amount of mycelium has formed. Precociously productive trees presented higher quantities of mycelium than nonproductive trees in the productivity onset study, while highly productive trees presented less quantities of mycelium than nonproductive trees in the productivity study. Trees with high but not excessive surface rock cover showed greater truffle production. Larger trees tended to display a burn earlier than smaller trees.
Keywords: burn; DNA soil mycelium; real-time PCR; rock cover; truffle; Tuber melanosporum

New data on ectomycorrhizae and soils of the Chinese truffles Tuber pseudoexcavatum and Tuber indicum, and their impact on truffle cultivation. - Garcia-Montero, Luis G.; Di Massimo, Gabriella; Manjon, Jose L.; García-Abril, Antonio (Mycorrhiza, 2008)
Chinese truffles serve as a good complement to the market for Tuber melanosporum (Périgord black truffle). However, Chinese truffles could be introduced accidentally or fraudulently into the plantations of Mediterranean truffles, and they could have a negative effect on truffle production and natural ecosystems. The study of Tuber species from China which are commercialized in Europe began 14 years ago. Tuber pseudoexcavatum was proposed as a new species, and this has been validated by some authors based on molecular and phylogenetic studies. We synthesize their ectomycorrhizae using samples from the type collection, and we compare T. pseudoexcavatum and Tuber indicum ectomycorrhizae. The ectomycorrhizae of these species have a morphology which is related to the ectomycorrhizae of T. melanosporum. We provide useful information for the rapid screening of the above-mentioned Chinese truffles ectomycorrhizae, for the quality control of commercial plants mycorrhized with Tuber. Moreover, we analyze the soil tolerance and the host plant affinity of T. pseudoexcavatum and T. indicum, in order to assess the capacity of both Chinese truffles to penetrate T. melanosporum plantations and habitats.
The following values have no corresponding Zotero field: accession-num: 18813959
Keywords: Chinese truffle; Ectomycorrhizae; Truffle cultivation; Truffle ecology; Truffle yield

New data on ectomycorrhizae and soils of the Chinese truffles Tuber pseudoexcavatum and Tuber indicum, and their impact on truffle cultivation. - Garcia-Montero, Luis G; Di Massimo, Gabriella; Manjon, Jose L; García-Abril, Antonio (Mycorrhiza, 2008)
Chinese truffles serve as a good complement to the market for Tuber melanosporum (Périgord black truffle). However, Chinese truffles could be introduced accidentally or fraudulently into the plantations of Mediterranean truffles, and they could have a negative effect on truffle production and natural ecosystems. The study of Tuber species from China which are commercialized in Europe began 14 years ago. Tuber pseudoexcavatum was proposed as a new species, and this has been validated by some authors based on molecular and phylogenetic studies. We synthesize their ectomycorrhizae using samples from the type collection, and we compare T. pseudoexcavatum and Tuber indicum ectomycorrhizae. The ectomycorrhizae of these species have a morphology which is related to the ectomycorrhizae of T. melanosporum. We provide useful information for the rapid screening of the above-mentioned Chinese truffles ectomycorrhizae, for the quality control of commercial plants mycorrhized with Tuber. Moreover, we analyze the soil tolerance and the host plant affinity of T. pseudoexcavatum and T. indicum, in order to assess the capacity of both Chinese truffles to penetrate T. melanosporum plantations and habitats.
Keywords: Chinese truffle; Ectomycorrhizae; Truffle cultivation; Truffle ecology; Truffle yield

New Eco-Friendly Gypsum Materials for Civil Construction - Eires, Rute; Camoes, Aires; Jalali, Said (ADVANCED MATERIALS FORUM IV, 2008)
The sustainable world's economic growth and people's life improvement greatly depend on the use of alternative products in the architecture and construction, such as industrial wastes conventionally called ``green materials{''}. This paper concerns the main results of an experimental work carried out with the objective of developing new composite materials based on gypsum and incorporating waste material as granulated cork, a by-product of cork industry, and cellulose fibres. a waste of paper industry. Such materials are intended to be used as composite boards for non structural elements of construction, such as dry walls and ceiling. Cork (bark of the plant Quercus Suber L), a substance largely produced in Portugal, is a material whose characteristics are of considerable interest for the construction industry. It is regarded as a strategic material with enormous potential by its reduced density, elasticity, compressibility; waterproof, vibration absorption, thermal and acoustic insulation efficiency \{[\}1]. During the first stage of this research work the gypsum binder and its properties Were Studied. Then, composites with mineral additions (added to increase the waterproofing and resistance) were also developed and submitted to tests to determine their physical and mechanical properties. In last stage, reinforced composites using different industrial by-products have been developed. This paper will present the properties and the manufacture methods used to produce the above mentioned eco-friendly composites that can case ways for using industrial wastes as new construction materials, with excellent inherent thermal and acoustic properties.
Keywords: Construction Technology; Cork Residue; Green materials; Sustainability; Waste recycling

New Eco-Friendly Gypsum Materials for Civil Construction - Eires, Rute; Camoes, Aires; Jalali, Said (ADVANCED MATERIALS FORUM IV, 2008)
The sustainable world's economic growth and people's life improvement greatly depend on the use of alternative products in the architecture and construction, such as industrial wastes conventionally called ``green materials{''}. This paper concerns the main results of an experimental work carried out with the objective of developing new composite materials based on gypsum and incorporating waste material as granulated cork, a by-product of cork industry, and cellulose fibres. a waste of paper industry. Such materials are intended to be used as composite boards for non structural elements of construction, such as dry walls and ceiling. Cork (bark of the plant Quercus Suber L), a substance largely produced in Portugal, is a material whose characteristics are of considerable interest for the construction industry. It is regarded as a strategic material with enormous potential by its reduced density, elasticity, compressibility; waterproof, vibration absorption, thermal and acoustic insulation efficiency \{[\}1]. During the first stage of this research work the gypsum binder and its properties Were Studied. Then, composites with mineral additions (added to increase the waterproofing and resistance) were also developed and submitted to tests to determine their physical and mechanical properties. In last stage, reinforced composites using different industrial by-products have been developed. This paper will present the properties and the manufacture methods used to produce the above mentioned eco-friendly composites that can case ways for using industrial wastes as new construction materials, with excellent inherent thermal and acoustic properties.
The following values have no corresponding Zotero field: periodical: ADVANCED MATERIALS FORUM IV pub-location: LAUBLSRUTISTR 24, CH-8717 STAFA-ZURICH, SWITZERLAND
Keywords: Construction Technology; Cork Residue; Green materials; Sustainability; Waste recycling

Non-enzymatic hydrolysis of fluorescein diacetate (FDA) in a Mediterranean oak (Quercus ilex L.) litter - Alarcón-Gutiérrez, E.; Floch, C.; Ruaudel, F.; Criquet, S. (European Journal of Soil Science, 2008)
We show the presence of interfering substances when the total microbial activity in litter samples is measured with fluorescein diacetate (FDA), and we propose some methodological modifications to avoid such interference. Three distinct litter layers (the OhLn, the OhLv and the OhLf) of evergreen oak (Quercus ilex L.) were characterized by 13C CPMAS NMR and the spectra show that the recalcitrant aromatic and phenolic compounds increase with the degree of degradation of litter. A wide range of sources of interference in the hydrolysis of FDA was found. To understand the origin of this interference, sterilized litter materials (i.e. γ-irradiated or autoclaved) and a wide range of organic substances (i.e. amino acids, glucose, sorbitol and organic humic acids) were investigated. Insignificant differences on the FDA hydrolysis activity (FDA activity) were found in the γ-irradiated and non-irradiated OhLn litter, indicating that γ-irradiation does not destroy enzymes. Conversely, after heat-sterilization of litter, samples showed FDA activity corresponding to 60, 34.8 and 30.8% (in the OhLn, the OhLv and the OhLf layers, respectively) of that of control litters. This indicates the presence of non-enzymatic interfering substances in the FDA assays. As the humification and litter depth increased, hydrolysis of FDA due to interferences decreased, indicating degradation and/or chelation of interfering substances. We hypothesize that lysine, arginine, histidine and cysteine are mainly responsible for the hydrolysis of FDA. We suggest that the use of phosphate buffer (50 mm, pH 7.0) with incubation < 30 minutes, in combination with a temperature between 30 and 40°C, produces insignificant interference in the determination of the final FDA activity in litter samples.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: CPMAS 13C NMR spectroscopy (voyant); hydrolysis; litter; Soil

Non-enzymatic hydrolysis of fluorescein diacetate (FDA) in a Mediterranean oak (Quercus ilex L.) litter - Alarcón-Gutiérrez, E; Floch, C; Ruaudel, F; Criquet, S (European Journal of Soil Science, 2008)
We show the presence of interfering substances when the total microbial activity in litter samples is measured with fluorescein diacetate (FDA), and we propose some methodological modifications to avoid such interference. Three distinct litter layers (the OhLn, the OhLv and the OhLf) of evergreen oak (Quercus ilex L.) were characterized by 13C CPMAS NMR and the spectra show that the recalcitrant aromatic and phenolic compounds increase with the degree of degradation of litter. A wide range of sources of interference in the hydrolysis of FDA was found. To understand the origin of this interference, sterilized litter materials (i.e. γ-irradiated or autoclaved) and a wide range of organic substances (i.e. amino acids, glucose, sorbitol and organic humic acids) were investigated. Insignificant differences on the FDA hydrolysis activity (FDA activity) were found in the γ-irradiated and non-irradiated OhLn litter, indicating that γ-irradiation does not destroy enzymes. Conversely, after heat-sterilization of litter, samples showed FDA activity corresponding to 60, 34.8 and 30.8% (in the OhLn, the OhLv and the OhLf layers, respectively) of that of control litters. This indicates the presence of non-enzymatic interfering substances in the FDA assays. As the humification and litter depth increased, hydrolysis of FDA due to interferences decreased, indicating degradation and/or chelation of interfering substances. We hypothesize that lysine, arginine, histidine and cysteine are mainly responsible for the hydrolysis of FDA. We suggest that the use of phosphate buffer (50 mm, pH 7.0) with incubation < 30 minutes, in combination with a temperature between 30 and 40°C, produces insignificant interference in the determination of the final FDA activity in litter samples.
Keywords: CPMAS 13C NMR spectroscopy (voyant); hydrolysis; litter; Soil

O Algoritmo BARCOR: Classificação de Cortiça para Rolhas Recorrendo a Quatro Atributos de Qualidade - Barreto, Luís Soares (Silva Lusitana, 2008)
t. The author proposes an analytical method named algorithm BARCOR that integrates TOPSIS ("Technique for Order Preference by Similarity to Ideal Solution"), regression, tree models and cluster analysis, to select the minimum number of attributes of cork quality to efficiently classify this material when used to the production of stoppers. When using attributes evenly weighted he shows that only the four attributes are sufficient. If unevenly weights of the attributes are used, this number can be reduced to three. He proposes two models with four and three attributes as explanatory variables to obtain expedite and preliminary classifications of the cork. He admits that the algorithm has potential to be applied in other similar situations.
The following values have no corresponding Zotero field: publisher: scielopt
Keywords: Algorithm; Classification; Cork; Quality; stoppers

O Algoritmo BARCOR: Classificação de Cortiça para Rolhas Recorrendo a Quatro Atributos de Qualidade - Barreto, Luís Soares (Silva Lusitana, 2008)
t. The author proposes an analytical method named algorithm BARCOR that integrates TOPSIS ("Technique for Order Preference by Similarity to Ideal Solution"), regression, tree models and cluster analysis, to select the minimum number of attributes of cork quality to efficiently classify this material when used to the production of stoppers. When using attributes evenly weighted he shows that only the four attributes are sufficient. If unevenly weights of the attributes are used, this number can be reduced to three. He proposes two models with four and three attributes as explanatory variables to obtain expedite and preliminary classifications of the cork. He admits that the algorithm has potential to be applied in other similar situations.
Keywords: Algorithm; Classification; Cork; Quality; stoppers

Oak seedling survival and growth along resource gradients in Mediterranean forests: implications for regeneration in current and future environmental scenarios - Gómez-Aparicio, L.; PÉREZ-RAMOS, I. M.; Mendoza, I.; Matías, L.; Quero, J. L.; Castro, J.; Zamora, R.; MARAÑON, T. (Oikos, 2008)
Understanding seedling performance across resource gradients is crucial for defining the regeneration niche of plant species under current environmental conditions and for predicting potential changes under a global change scenario. A 2-year field experiment was conducted to determine how seedling survival and growth of two evergreen and two deciduous Quercus species vary along gradients of light and soil properties in two Mediterranean forests with contrasting soils and climatic conditions. Half the seedlings were subjected to an irrigation treatment during the first year to quantify the effects on performance of an alteration in the summer drought intensity. Linear and non-linear models were parameterized and compared to identify major resources controlling seedling performance. We found both site-specific and general patterns of regeneration. Strong site-specificity was found in the identity of the best predictors of seedling survival: survival decreased linearly with increasing light (i.e. increasing desiccation risk) in the drier site, whereas it decreased logistically with increasing spring soil water content (i.e. increasing waterlogging risk) in the wetter site. We found strong empirical support for multiple resource limitation at the drier site, the response to light being modulated by the availability of soil resources (water and P). Evidence for regeneration niche partitioning among Quercus species was only found at the wetter site. However, at both sites Quercus species shared the same response to summer drought alleviation through water addition: increased first-year survival but not final survival (i.e. after two years). This suggests that extremely dry summers (i.e. the second summer in the experiment) can cancel out the positive effects of previous wetter summers. Therefore, an increase in the intensity and frequency of summer drought with climate change might cause a double negative impact on Quercus regeneration, due to a general reduction in survival probability and the annulment of the positive effects of (infrequent) ‘wet’ years. Overall, results presented in this study are a major step towards the development of a mechanistic model of Mediterranean forest dynamics that incorporates the idiosyncrasies and generalities of tree regeneration in these systems, and that allow simulation and prediction of the ecological consequences of resource level alterations due to global change.
Keywords: abiotic factors; growth (voyant); light; Mediterranean forests; Quercus; Regeneration; seedling survival; soil conditions; summer drought

Ontogenetic changes in stomatal and biochemical limitations to photosynthesis of two co-occurring Mediterranean oaks differing in leaf life span - Juárez-López, Francisco José; Escudero, Alfonso; Mediavilla, Sonia (Tree Physiology, 2008)
A quantitative analysis was applied to the stomatal and biochemical limitations to light-saturated net photosynthesis under optimal field conditions in mature trees and seedlings of the co-occurring evergreen oak, Quercus ilex L., and the deciduous oak, Q. faginea Lam. Stomatal limitation to photosynthesis, maximal Rubisco activity and electron transport rate were determined from assimilation versus intercellular leaf carbon dioxide concentration response curves of leaves that were subsequently analyzed for nitrogen (N) concentration, mass per unit area, thickness and percent internal air space. In both species, seedlings had a lower leaf mass per unit area, thickness and leaf N concentration than mature trees. The root system of seedlings during their third year after planting was dominated by a taproot. A lower leaf N concentration of seedlings was associated with lower maximal Rubisco activity and electron transport rate and with assimilation rates similar to or lower than those of mature trees, despite the higher stomatal conductances and potential photosynthetic nitrogen-use efficiencies of seedlings. Consequently, stomatal limitation to photosynthesis increased with tree age in both species. In both seedlings and mature trees, a lower assimilation rate in Q. ilex than in Q. faginea was associated with lower stomatal conductance, N allocation to photosynthetic functions, maximal Rubisco activity and electron transport rate, and potential photosynthetic nitrogen-use efficiency but greater leaf thickness and leaf mass per unit area. Tree-age-related changes differed quantitatively between species, and the characteristics of the two species were more similar in seedlings than in mature trees. Despite higher stomatal conductances, seedlings are more N limited than adult trees, which contributes to lower biochemical efficiency.
10.1093/treephys/28.3.367
Keywords: A–ci response curves; biochemical capacity; leaf morphology; leaf N allocation; mature trees; Quercus faginea; Quercus ilex; seedlings; Stomatal conductance

Opzioni selvicolturali su cedui di leccio del Gargano: risultati a 14 anni dall'avvio della sperimentazione - La Marca, O; Marziliano, P A; Scopigno, D (iForest - Biogeosciences and Forestry, 2008)
In the frame of a long-term research program concerning management of ageing holm oak coppices, results available after 14 growing seasons are reported in present paper. Experimental treatments include: A) 50 standards per hectare, all of the same age; B) 250 standards per hectare, all of the same age; C) 140 standards per hectare, with two different ages; D) conversion to high forest; E) natural evolution (control). A total of 15 permanent plots were established (5 treatments x 3 replicates per treatment) and the experimental design used is that of randomised blocks. Based on observations concerning seedlings and shoots development and standards growth and competitive effects, the following preliminary results may be highlighted: i) recovering the traditional coppicing system with few standards per hectare represents a valid option from both ecological and shoots growth point of view; the stools, with few standards per hectare, showed a larger number of sprouts, provided with a higher average height and larger diameters; ii) uneven-aged standards represent a good alternative form the points of view of both landscape impact immediately after felling operations and stand resistance to climatic damages; iii) a good alternative is to apply conversion treatments to high forest, whenever their site quality allows these operations.
Keywords: Conversion To High Forest; coppice; Holm oak; Regeneration; Standard Density

Orbital- and sub-orbital-scale climate impacts on vegetation of the western Mediterranean basin over the last 48,000 yr - Fletcher, William J; Sánchez Goñi, Maria Fernanda (Quaternary Research, 2008)
High-resolution pollen analysis of Alborán Sea core MD95-2043 provides a 48-ka continuous vegetation record that can be directly correlated with sea surface and deep-water changes. The reliability of this record is supported by comparison with that of Padul (Sierra Nevada, Spain). Marine Isotope Stage (MIS) 3 was characterised by ﬂuctuations in Quercus forest cover in response to Dansgaard-Oeschger climate variability. MIS 2 was characterised by the dominance of semi-desert vegetation. Despite overall dry and cold conditions during MIS 2, Heinrich events (HEs) 2 and 1 were distinguished from the last glacial maximum by more intensely arid conditions. Taxon-speciﬁc vegetation responses to a tripartite climatic structure within the HEs are observed. In MIS 1, the Bölling-Allerød was marked by rapid afforestation, while a re-expansion of semidesert environments occurred during the Younger Dryas. The maximum development of mixed Quercus forest occurred between 11.7 and 5.4 cal ka BP, with forest decline since 5.4 cal ka BP. On orbital timescales, a long-term expansion of semi-desert vegetation from MIS 3 into MIS 2 reﬂects global ice-volume trends, while Holocene arboreal decline reﬂects summer insolation decrease. The inﬂuence of precession on the amplitude of forest development and vegetation composition is also detected
Keywords: Dansgaard-Oeschger variability; Heinrich events; Holocene; Iberian margin; Land–sea correlation; LGM; Marine palynology; Mediterranean Region; Precession

Orbital- and sub-orbital-scale climate impacts on vegetation of the western Mediterranean basin over the last 48,000 yr - Fletcher, William J.; Sánchez Goñi, Maria Fernanda (Quaternary Research, 2008)
High-resolution pollen analysis of Alborán Sea core MD95-2043 provides a 48-ka continuous vegetation record that can be directly correlated with sea surface and deep-water changes. The reliability of this record is supported by comparison with that of Padul (Sierra Nevada, Spain). Marine Isotope Stage (MIS) 3 was characterised by ﬂuctuations in Quercus forest cover in response to Dansgaard-Oeschger climate variability. MIS 2 was characterised by the dominance of semi-desert vegetation. Despite overall dry and cold conditions during MIS 2, Heinrich events (HEs) 2 and 1 were distinguished from the last glacial maximum by more intensely arid conditions. Taxon-speciﬁc vegetation responses to a tripartite climatic structure within the HEs are observed. In MIS 1, the Bölling-Allerød was marked by rapid afforestation, while a re-expansion of semidesert environments occurred during the Younger Dryas. The maximum development of mixed Quercus forest occurred between 11.7 and 5.4 cal ka BP, with forest decline since 5.4 cal ka BP. On orbital timescales, a long-term expansion of semi-desert vegetation from MIS 3 into MIS 2 reﬂects global ice-volume trends, while Holocene arboreal decline reﬂects summer insolation decrease. The inﬂuence of precession on the amplitude of forest development and vegetation composition is also detected
The following values have no corresponding Zotero field: publisher: University of Washington
Keywords: Dansgaard-Oeschger variability; Heinrich events; Holocene; Iberian margin; Land–sea correlation; LGM; Marine palynology; Mediterranean Region; Precession

Pathogenicity of Pythium spiculum and P-sterilum on feeder roots of Quercus rotundifolia - Jimenez, J. J.; Sanchez, J. E.; Romero, M. A.; Belbahri, L.; Trapero, A.; Lefort, F.; Sanchez, M. E. (PLANT PATHOLOGY, 2008)
APSAPSThe following values have no corresponding Zotero field: pub-location: 9600 GARSINGTON RD, OXFORD OX4 2DQ, OXON, ENGLAND publisher: BLACKWELL PUBLISHING
Keywords: pathogenic; Pythium spiculum; Pythium sterilum; Quercus ilex

Pathogenicity of Pythium spiculum and P-sterilum on feeder roots of Quercus rotundifolia - Jimenez, J J; Sanchez, J E; Romero, M A; Belbahri, L; TRAPERO, A; Lefort, F; SÁNCHEZ, M E (PLANT PATHOLOGY, 2008)
APS
Keywords: pathogenic; Pythium spiculum; Pythium sterilum; Quercus ilex

Phenolic variations in mite infected leaves of Quercus ilex L. (Fagaceae) - Karioti, A; Tooulakou, G; Karabourniotis, G; Bilia, A R; Skaltsa, H (PLANTA MEDICA, 2008)
Structures on the surfaces of leaves, such as dense layers of non-glandular trichomes, strongly affect phylloplane mite activities. On the other hand the feeding of eriophyoid mites on leaf surfaces can cause hyperplasia of leaf trichomes (erinea formation). In many cases the hyperplasia is accompanied by the accumulation of pigments within trichome cells, causing an impressive red-brown colouration of the eri- neum. There is no information, however, on the structure of these pigments as well as on the chemical alterations in the phenolic content of plant trichomes in response to mite attack. Erinea formation on the abaxial surface of Quercus ilex leaves upon Aceria ilicis (Acari: Eriophyoidea) attack provides an excel- lent model on this topic. Differences in the structure and chemical composition of isolated trichomes derived either from healthy (normal trichomes) or mite attacked (hypertrophic trichomes) leaves were examined. Carbon investment was comparable between the two different trichome types, but the cell walls of the hypertrophic trichomes appeared thinner and did not contain microcrystalline cellulose. Observations under the fluorescence microscope showed that the emitted fluorescence was different between the two trichome types, indicating a different composition in fluorescencing phenolic com- pounds. The chemical analyses confirmed that hypertrophic trichomes contained higher concentrations of the feeding deterrents proanthocyanidin B3 and catechin, as well as of quercetin-3-O-glucoside, but lower concentrations of acylated flavonoid glycosides, than the normal ones. The results showed that the structural and functional changes in leaf trichomes upon mite attack may be an effort of the leaf to compensate the damage caused by the pest
Keywords: Fagaceae; Leaf trichomes; Mites; phenolics; Quercus ilex

Photoprotective responses of Mediterranean and Atlantic trees to the extreme heat-wave of summer 2003 in Southwestern Europe - García-Plazaola, José Ignacio; Esteban, Raquel; Hormaetxe, Koldobika; Fernández-Marín, Beatriz; Becerril, José Maria (Trees, 2008)
Summer 2003 was extremely hot in Europe. High light in combination with heat and drought exacerbates the generation of photo-oxidative stress. Under these conditions photoprotective responses can be critical for plant survival. Photoprotection was analysed in 2003 in several Mediterranean and Atlantic woody species. These data were compared with previous summers (1998, 1999 and 2001) to evaluate the potential acclimation for each species. A pattern of changes consisting on a decrease in chlorophyll, ascorbate and Fv/Fm and an increase in tocopherol, xanthophyll cycle pigments (VAZ) and deepoxidation index was regularly observed. Acclimation potential was measured by the use of the plasticity index for each parameter. Mediterranean species were more plastic than Atlantic ones. The latter were unable to increase antioxidant pools to the same extent or to downregulate the efﬁciency of light energy conversion. These results indicate that most Mediterranean species are able to perform an efﬁcient acclimation to heat stress, whilst Atlantic species will be more affected by climate warming.
Keywords: á summer 2003; antioxidants; antioxidants á heat-wave á; heat-wave; mediterranean species; mediterranean species á photoprotection; photoprotection; summer 2003

Photoprotective responses of Mediterranean and Atlantic trees to the extreme heat-wave of summer 2003 in Southwestern Europe - García-Plazaola, José Ignacio; Esteban, Raquel; Hormaetxe, Koldobika; Fernández-Marín, Beatriz; Becerril, José Maria (Trees, 2008)
Summer 2003 was extremely hot in Europe. High light in combination with heat and drought exacerbates the generation of photo-oxidative stress. Under these conditions photoprotective responses can be critical for plant survival. Photoprotection was analysed in 2003 in several Mediterranean and Atlantic woody species. These data were compared with previous summers (1998, 1999 and 2001) to evaluate the potential acclimation for each species. A pattern of changes consisting on a decrease in chlorophyll, ascorbate and Fv/Fm and an increase in tocopherol, xanthophyll cycle pigments (VAZ) and deepoxidation index was regularly observed. Acclimation potential was measured by the use of the plasticity index for each parameter. Mediterranean species were more plastic than Atlantic ones. The latter were unable to increase antioxidant pools to the same extent or to downregulate the efﬁciency of light energy conversion. These results indicate that most Mediterranean species are able to perform an efﬁcient acclimation to heat stress, whilst Atlantic species will be more affected by climate warming.
Keywords: á summer 2003; antioxidants; antioxidants á heat-wave á; heat-wave; mediterranean species; mediterranean species á photoprotection; photoprotection; summer 2003

Photosynthesis and photoprotective strategies in Laurus nobilis L. and Quercus ilex L. under summer drought and winter cold - Arena, C.; Vitale, L.; Virzo De Santo, A. (Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology, 2008)
Abstract Photosynthesis and photoprotective mechanisms were investigated in the field on Laurus nobilis L. and Quercus ilex L. leaves exposed to summer drought (July) and winter cold (February) conditions compared with no-stress conditions (May). In July, net photosynthetic rate (A) and stomatal conductance (g s) decreased significantly compared with May in both species; conversely the highest ETR/A ratio and no difference in non-photochemical quenching (NPQ) was observed. In February A, g s and ETR/A declined compared with May but the highest NPQ were found in both species. Our data suggest that during summer, an increase of photochemical alternative pathways to carbon reduction, were able to effectively protect the photosynthetic apparatus under drought. In winter, the thermal dissipation of excess absorbed light constitutes the main safety valve for the photosynthetic apparatus.
doi: 10.1080/11263500802410819doi: 10.1080/11263500802410819The following values have no corresponding Zotero field: publisher: Taylor & Francis
Keywords: Dissipative processes; L. nobilis; leaf gas-exchange; Q. ilex; summer drought; winter cold

Photosynthesis and photoprotective strategies in Laurus nobilis L. and Quercus ilex L. under summer drought and winter cold - Arena, C; Vitale, L; Virzo de Santo, A (Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology, 2008)
Abstract Photosynthesis and photoprotective mechanisms were investigated in the field on Laurus nobilis L. and Quercus ilex L. leaves exposed to summer drought (July) and winter cold (February) conditions compared with no-stress conditions (May). In July, net photosynthetic rate (A) and stomatal conductance (g s) decreased significantly compared with May in both species; conversely the highest ETR/A ratio and no difference in non-photochemical quenching (NPQ) was observed. In February A, g s and ETR/A declined compared with May but the highest NPQ were found in both species. Our data suggest that during summer, an increase of photochemical alternative pathways to carbon reduction, were able to effectively protect the photosynthetic apparatus under drought. In winter, the thermal dissipation of excess absorbed light constitutes the main safety valve for the photosynthetic apparatus.
doi: 10.1080/11263500802410819
Keywords: Dissipative processes; L. nobilis; leaf gas-exchange; Q. ilex; summer drought; winter cold

Phytoclimatic versatility and potential diversity of natural arboreal forest cover in peninsular Spain - Garcia Lopez, J. M.; ALLUÉ CAMACHO, C. (INVESTIGACION AGRARIA-SISTEMAS Y RECURSOS FORESTALES, 2008)
A multivariate methodology was assayed to evaluate the phytoclimatic versatility of peninsular Spain and how this relates to the potential diversity of natural tree covers. The instances of greatest phytoclimatic versatility occur in a range of altitude between 1000 and 1300 m; these are cool phytoclimates with only short, low-intensity periods of aridity. These factorial ambits of maximum versatility correspond chiefly to the substeppe nemoral subtype VI(VII), followed by genuine nemoral VI and humid nemoromediterranean VI(IV)(2) subtypes. The lowest values of versatility and potential diversity correspond to dry genuine Mediterranean (IV(1)) or transitional Mediterranean IV(VI)(1) subtypes and to alpine oroborealoid or oroarcticoid subtypes. In geographical terms, intermediate mountain areas in the north of the Peninsula and some massifs in the southern half score the highest in the Diversity Index used. The lowest scores are found in the southern half of the Peninsula, although in the northern half low scores are also found for littoral areas, interior areas of the Duero and Ebro basins and alpine areas. Autoecological phytoclimatic spectra headed by stands of Pinus nigra and Quercus petraea present the greatest phytoclimatic versatility, while those headed by Quercus ilex ballota and Pinus uncinata stands present the least versatility. This article offers new methodological horizons for the study of the effects of climate change on plant diversity.
The following values have no corresponding Zotero field: pub-location: CTRA CORUNA KM 7 5, MADRID, 28040, SPAIN publisher: INST NACIONAL INVESTIGACION TECHNOLOGIA AGRARIA ALIMENTARIA
Keywords: Biodiversity; climate change; competition; Simpson Index; suitability

Phytoclimatic versatility and potential diversity of natural arboreal forest cover in peninsular Spain - Garcia Lopez, J M; ALLUÉ CAMACHO, C (INVESTIGACION AGRARIA-SISTEMAS Y RECURSOS FORESTALES, 2008)
A multivariate methodology was assayed to evaluate the phytoclimatic versatility of peninsular Spain and how this relates to the potential diversity of natural tree covers. The instances of greatest phytoclimatic versatility occur in a range of altitude between 1000 and 1300 m; these are cool phytoclimates with only short, low-intensity periods of aridity. These factorial ambits of maximum versatility correspond chiefly to the substeppe nemoral subtype VI(VII), followed by genuine nemoral VI and humid nemoromediterranean VI(IV)(2) subtypes. The lowest values of versatility and potential diversity correspond to dry genuine Mediterranean (IV(1)) or transitional Mediterranean IV(VI)(1) subtypes and to alpine oroborealoid or oroarcticoid subtypes. In geographical terms, intermediate mountain areas in the north of the Peninsula and some massifs in the southern half score the highest in the Diversity Index used. The lowest scores are found in the southern half of the Peninsula, although in the northern half low scores are also found for littoral areas, interior areas of the Duero and Ebro basins and alpine areas. Autoecological phytoclimatic spectra headed by stands of Pinus nigra and Quercus petraea present the greatest phytoclimatic versatility, while those headed by Quercus ilex ballota and Pinus uncinata stands present the least versatility. This article offers new methodological horizons for the study of the effects of climate change on plant diversity.
Keywords: Biodiversity; climate change; competition; Simpson Index; suitability

Plant and carabid beetle species diversity in relation to forest type and structural heterogeneity - Taboada, Ángela; Tárrega, Reyes; Calvo, Leonor; Marcos, Elena; Marcos, José Antonio; Salgado, José María (European Journal of Forest Research, 2008)
The aim of this study was to evaluate the inﬂuence of forest structure (mainly resulting from human uses) and forest type (the identity of the dominant tree species) on biodiversity. We determined the diversity of two taxonomical groups: the understory vegetation and the edaphic carabid beetle fauna. We selected eight types of forest ecosystems (ﬁve replicates or stands per forest type): pine (Pinus sylvestris) plantations of three age classes (10, 40 and 80 years since reforestation), an old-growth relict natural pine forest, and four types of oak (Quercus pyrenaica) stands: mature forests with livestock grazing and ﬁrewood extraction, mature forests where uses have been abandoned, ‘‘dehesa’’ ecosystems and shrubby oak ecosystems. The results obtained by a global PCA analysis indicated that both tree size and dominant species inﬂuenced the ordination of the 40 forest stands. In general, carabids were more sensitive to changes in forest heterogeneity and responded more clearly to the analysed structural variables than the understory vegetation, although the species richness of both groups was signiﬁ- cantly correlated and higher in case of oak forests. Pine forest ecosystems were characterised by the lowest species richness for both taxonomical groups, the lowest plant diversity and by the lowest coefﬁcients of variation and, consequently, low structural heterogeneity. As a result, it was very difﬁcult to discriminate the effects of the spatial heterogeneity and the dominant tree species on biodiversity
Keywords: Biodiversity; carabid beetles; heterogeneity; oak forests; pine plantations; understory vegetation

Plant and carabid beetle species diversity in relation to forest type and structural heterogeneity - Taboada, Ángela; Tárrega, Reyes; Calvo, Leonor; Marcos, Elena; Marcos, José Antonio; Salgado, José María (European Journal of Forest Research, 2008)
The aim of this study was to evaluate the inﬂuence of forest structure (mainly resulting from human uses) and forest type (the identity of the dominant tree species) on biodiversity. We determined the diversity of two taxonomical groups: the understory vegetation and the edaphic carabid beetle fauna. We selected eight types of forest ecosystems (ﬁve replicates or stands per forest type): pine (Pinus sylvestris) plantations of three age classes (10, 40 and 80 years since reforestation), an old-growth relict natural pine forest, and four types of oak (Quercus pyrenaica) stands: mature forests with livestock grazing and ﬁrewood extraction, mature forests where uses have been abandoned, ‘‘dehesa’’ ecosystems and shrubby oak ecosystems. The results obtained by a global PCA analysis indicated that both tree size and dominant species inﬂuenced the ordination of the 40 forest stands. In general, carabids were more sensitive to changes in forest heterogeneity and responded more clearly to the analysed structural variables than the understory vegetation, although the species richness of both groups was signiﬁ- cantly correlated and higher in case of oak forests. Pine forest ecosystems were characterised by the lowest species richness for both taxonomical groups, the lowest plant diversity and by the lowest coefﬁcients of variation and, consequently, low structural heterogeneity. As a result, it was very difﬁcult to discriminate the effects of the spatial heterogeneity and the dominant tree species on biodiversity
Keywords: Biodiversity; carabid beetles; heterogeneity; oak forests; pine plantations; understory vegetation

Plant MTs-long neglected members of the metallothionein superfamily - Freisinger, Eva (DALTON TRANSACTIONS, 2008)
Occurrence of metallothioneins (MTs) was initially thought to be restricted to the animal kingdom, and the corresponding functions such as detoxification of heavy metal ions were assumed to be taken over in plants by the enzymatically synthesized phytochelatins. This perception was revised in the past years, and the existence of plant metallothioneins is generally accepted. Compared to the vertebrate forms, members of the plant MT family display a significantly larger sequence diversity, however, surprisingly little information is available concerning their possible functions, properties, and structures. Gene expression studies, and thus studies on the mRNA level, are the major source of data aiming at elucidating the function of plant MTs. However, so far it is not possible to unambiguously assign a specific function to a given metallothionein as proposed functions overlap, are complementary to each other, or even contradictory results are obtained. With respect to the structures and properties of plant metallothioneins even less scientific contributions are available illustrating the early stages, in which this research area resides. Existing data covers the metal ion content of the different plant metallothionein species and the pH stabilities of the resulting metal-thiolate clusters. Further, for a limited selection of proteins the number of clusters formed has been proposed and predictions towards the secondary structure of the protein backbone made. A recently determined three-dimensional structure of the larger domain of the wheat metallothionein E(c)-1 describes a metal ion coordination mode unprecedented for any metallothionein so far.
APS
Keywords: Heavy metals; plant metallothioneins

Plant MTs-long neglected members of the metallothionein superfamily - Freisinger, Eva (DALTON TRANSACTIONS, 2008)
Occurrence of metallothioneins (MTs) was initially thought to be restricted to the animal kingdom, and the corresponding functions such as detoxification of heavy metal ions were assumed to be taken over in plants by the enzymatically synthesized phytochelatins. This perception was revised in the past years, and the existence of plant metallothioneins is generally accepted. Compared to the vertebrate forms, members of the plant MT family display a significantly larger sequence diversity, however, surprisingly little information is available concerning their possible functions, properties, and structures. Gene expression studies, and thus studies on the mRNA level, are the major source of data aiming at elucidating the function of plant MTs. However, so far it is not possible to unambiguously assign a specific function to a given metallothionein as proposed functions overlap, are complementary to each other, or even contradictory results are obtained. With respect to the structures and properties of plant metallothioneins even less scientific contributions are available illustrating the early stages, in which this research area resides. Existing data covers the metal ion content of the different plant metallothionein species and the pH stabilities of the resulting metal-thiolate clusters. Further, for a limited selection of proteins the number of clusters formed has been proposed and predictions towards the secondary structure of the protein backbone made. A recently determined three-dimensional structure of the larger domain of the wheat metallothionein E(c)-1 describes a metal ion coordination mode unprecedented for any metallothionein so far.
APSAPSThe following values have no corresponding Zotero field: pub-location: THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND publisher: ROYAL SOC CHEMISTRY
Keywords: Heavy metals; plant metallothioneins

Plant physiological and environmental controls over the exchange of acetaldehyde between forest canopies and the atmosphere - Jardine, K; Harley, P; Karl, T; Guenther, A; Lerdau, M; Mak, J E (BIOGEOSCIENCES, 2008)
We quantified fine scale sources and sinks of gas phase acetaldehyde in two forested ecosystems in the US. During the daytime, the upper canopy behaved as a net source while at lower heights, reduced emission rates or net uptake were observed. At night, uptake generally predominated throughout the canopies. Net ecosystem emission rates were inversely related to foliar density due to the extinction of light in the canopy and a respective decrease of the acetaldehyde compensation point. This is supported by branch level studies revealing much higher compensation points in the light than in the dark for poplar (Populus deltoides) and holly oak (Quercus ilex) implying a higher light/temperature sensitivity for acetaldehyde production relative to consumption. The view of stomata as the major pathway for acetaldehyde exchange is supported by strong linear correlations between branch transpiration rates and acetaldehyde exchange velocities for both species. In addition, natural abundance carbon isotope analysis of gas-phase acetaldehyde during poplar branch fumigation experiments revealed a significant kinetic isotope effect of 5.1 +/- 0.3 parts per thousand associated with the uptake of acetaldehyde. Similar experiments with dry dead poplar leaves showed no fractionation or uptake of acetaldehyde, confirming that this is only a property of living leaves. We suggest that acetaldehyde belongs to a potentially large list of plant metabolites where stomatal resistance can exert long term control over both emission and uptake rates due to the presence of both source(s) and sink(s) within the leaf which strongly buffer large changes in concentrations in the substomatal airspace due to changes in stomatal resistance. We conclude that the exchange of acetaldehyde between plant canopies and the atmosphere is fundamentally controlled by ambient acetaldehyde concentrations, stomatal resistance, and the compensation point which is a function of light/temperature.
APS
Keywords: acetaldehydes; emission; Populus deltoides; Quercus ilex; stomatal resistance

Predator abundance in relation to small game management in southern Portugal: conservation implications - Beja, Pedro; Gordinho, Luís; Reino, Luís; Loureiro, Filipa; Santos-Reis, Margarida; Borralho, Rui (European Journal of Wildlife Research, 2008)
The interaction between hunting interests and legally protected predators is often a contentious conservation problem, requiring detailed understanding of predator responses to game management. This issue was addressed in southern Portugal in a treatment-control natural experiment, whereby the abundances of small game, corvids, birds of prey and carnivores were compared in 12 game estates (>500 ha) and 12 matching areas with similar sizes and land uses but no gamemanagement. European rabbits (Oryctolagus cuniculus), Iberian hares (Lepus granatensis) and, less so, red-legged partridges (Alectoris rufa) were far more numerous in game estates than elsewhere. Among legally controlled species, there were less Eurasian jays (Garrulus glandarius) but more red foxes (Vulpes vulpes) in game estates, though the latter were primary targets of predator culling. Fox abundance within game estates varied inversely with an index of management intensity (density of small game feeding sites) and increased along with hare abundance. As for protected species, only common kestrels (Falco tinnunculus) and genets (Genetta genetta) were fewer in game estates. The abundance of raptors within game estates varied inversely with gamekeeper density, whereas that of common buzzards (Buteo buteo) increased along with rabbit abundance. Overall, there was little evidence that game management reduced local predator abundances, except in the most intensively managed estates. Game estates provided concentrations of prey that was scarce elsewhere, which may have favoured increased abundances of some predators. Further investigations are needed to find out whether high prey densities may attract predators to game estates with increased mortality risk, which may thus become population sinks for protected species.
Keywords: birds of prey; carnivores; conservation conflict; hunting; predator control

Predator abundance in relation to small game management in southern Portugal: conservation implications - Beja, Pedro; Gordinho, Luís; Reino, Luís; Loureiro, Filipa; Santos-Reis, Margarida; Borralho, Rui (European Journal of Wildlife Research, 2008)
The interaction between hunting interests and legally protected predators is often a contentious conservation problem, requiring detailed understanding of predator responses to game management. This issue was addressed in southern Portugal in a treatment-control natural experiment, whereby the abundances of small game, corvids, birds of prey and carnivores were compared in 12 game estates (>500 ha) and 12 matching areas with similar sizes and land uses but no gamemanagement. European rabbits (Oryctolagus cuniculus), Iberian hares (Lepus granatensis) and, less so, red-legged partridges (Alectoris rufa) were far more numerous in game estates than elsewhere. Among legally controlled species, there were less Eurasian jays (Garrulus glandarius) but more red foxes (Vulpes vulpes) in game estates, though the latter were primary targets of predator culling. Fox abundance within game estates varied inversely with an index of management intensity (density of small game feeding sites) and increased along with hare abundance. As for protected species, only common kestrels (Falco tinnunculus) and genets (Genetta genetta) were fewer in game estates. The abundance of raptors within game estates varied inversely with gamekeeper density, whereas that of common buzzards (Buteo buteo) increased along with rabbit abundance. Overall, there was little evidence that game management reduced local predator abundances, except in the most intensively managed estates. Game estates provided concentrations of prey that was scarce elsewhere, which may have favoured increased abundances of some predators. Further investigations are needed to find out whether high prey densities may attract predators to game estates with increased mortality risk, which may thus become population sinks for protected species.
Keywords: birds of prey; carnivores; conservation conflict; hunting; predator control

Real-time PCR identification and detection of Fuscoporia torulosa in Quercus ilex - Campanile, G; Schena, L; Luisi, N (Plant Pathology, 2008)
Fuscoporia torulosa is the causal agent of white alveolar wood decay on several species including a large number of forest trees. Early detection of the fungus is essential to identify diseased trees before spread occurs to healthy plants. However, current detection methods based on isolation from infected tissues on semi-selective media are laborious, time consuming and require expertise in identifying the pathogen after isolation. In the present study, a rapid and reliable Scorpion-PCR based molecular method to identify and detect F. torulosa in planta was developed in a highly polymorphic portion of the internal transcribed spacer (ITS) regions. Specificity of primers and probe was assessed by means of both BLAST analyses and by using genomic DNA from 131 F. torulosa isolates and 43 other fungi and oomycetes from different hosts and geographic areas. In Scorpion-PCR the limit of detection was 1 pg of total DNA and a high correlation (r2 = 0·996) was achieved between target DNA quantity and cycle threshold (Ct). Real-time PCR combined with effective procedures for DNA extraction enabled the detection of F. torulosa from naturally infected tissues of oaks with and without fruit bodies in approximately 6 h. Comparative testing showed that detection of F. torulosa in wood samples is more sensitive and reliable with real-time PCR than with conventional isolation.
Keywords: molecular detection; Phellinus torulosus; Scorpion-PCR; white rot; wood decay

Real-time PCR identification and detection of Fuscoporia torulosa in Quercus ilex - Campanile, G.; Schena, L.; Luisi, N. (Plant Pathology, 2008)
Fuscoporia torulosa is the causal agent of white alveolar wood decay on several species including a large number of forest trees. Early detection of the fungus is essential to identify diseased trees before spread occurs to healthy plants. However, current detection methods based on isolation from infected tissues on semi-selective media are laborious, time consuming and require expertise in identifying the pathogen after isolation. In the present study, a rapid and reliable Scorpion-PCR based molecular method to identify and detect F. torulosa in planta was developed in a highly polymorphic portion of the internal transcribed spacer (ITS) regions. Specificity of primers and probe was assessed by means of both BLAST analyses and by using genomic DNA from 131 F. torulosa isolates and 43 other fungi and oomycetes from different hosts and geographic areas. In Scorpion-PCR the limit of detection was 1 pg of total DNA and a high correlation (r2 = 0·996) was achieved between target DNA quantity and cycle threshold (Ct). Real-time PCR combined with effective procedures for DNA extraction enabled the detection of F. torulosa from naturally infected tissues of oaks with and without fruit bodies in approximately 6 h. Comparative testing showed that detection of F. torulosa in wood samples is more sensitive and reliable with real-time PCR than with conventional isolation.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: molecular detection; Phellinus torulosus; Scorpion-PCR; white rot; wood decay

Regional phenological models for forecasting the start and peak of the Quercus pollen season in Spain - García-Mozo, H.; Chuine, I.; Aira, M. J. J.; Belmonte, J.; Bermejo, D.; Díaz de la Guardia, C.; Elvira, B.; Gutiérrez, M.; Rodríguez-Rajo, J.; Ruiz, L.; Trigo, M. M. M.; Tormo, R.; et al. (Agricultural and Forest Meteorology, 2008)
he study sought to achieve the broadest possible spatial and temporal predictions by examining genetic variations in the timing of ﬂowering between populations of the Iberian Quercus species using pollen data from 15 sites in Spain. The speciﬁc objective of the study was to develop and ﬁt regional phenological model to predict the ﬂowering start and ﬂowering peak of Quercus species in the Iberian Peninsula by ascertaining whether potentially signiﬁcant genetic variations in the timing of ﬂowering required different phenological models or if, on the contrary, regional models for several localities can explain the variability detected in Quercus phenology in Spain. Model estimates did not vary greatly as a function of environment within similar climate areas where the same species grew; thus, model estimates of the temperature response of individuals growing in similar climate areas did not differ signiﬁcantly. The percentage of variance explained by models was greater in models ﬁtted with local data (75–97%). Nevertheless, acceptable results were also obtained using regional models (55–85%). The lowest value was found for the Simplifed Model including all Spanish sites together (51%).
Keywords: Aerobiology; Modelling; oak forest; Phenology; pollen; Quercus

Regional phenological models for forecasting the start and peak of the Quercus pollen season in Spain - García-Mozo, H.; Chuine, I.; Aira, M.J. J; Belmonte, J.; Bermejo, D.; Díaz de la Guardia, C.; Elvira, B.; Gutiérrez, M.; Rodríguez-Rajo, J.; Ruiz, L.; Trigo, M.M. M; Tormo, R.; et al. (Agricultural and Forest Meteorology, 2008)
he study sought to achieve the broadest possible spatial and temporal predictions by examining genetic variations in the timing of ﬂowering between populations of the Iberian Quercus species using pollen data from 15 sites in Spain. The speciﬁc objective of the study was to develop and ﬁt regional phenological model to predict the ﬂowering start and ﬂowering peak of Quercus species in the Iberian Peninsula by ascertaining whether potentially signiﬁcant genetic variations in the timing of ﬂowering required different phenological models or if, on the contrary, regional models for several localities can explain the variability detected in Quercus phenology in Spain. Model estimates did not vary greatly as a function of environment within similar climate areas where the same species grew; thus, model estimates of the temperature response of individuals growing in similar climate areas did not differ signiﬁcantly. The percentage of variance explained by models was greater in models ﬁtted with local data (75–97%). Nevertheless, acceptable results were also obtained using regional models (55–85%). The lowest value was found for the Simplifed Model including all Spanish sites together (51%).
Keywords: Aerobiology; Modelling; oak forest; Phenology; pollen; Quercus

The relationship between cork oak growth patterns and soil, slope and drainage in a cork oak woodland in Southern Portugal - Costa, Augusta; Madeira, Manuel; Oliveira, Ângelo Carvalho (Forest Ecology and Management, 2008)
The inﬂuence of soil type, slope and drainage on tree growth patterns (density, tree size, crown canopy cover and cork yield) was assessed in a cork oak montado, located in Central-western Portugal, based on a GIS approach followed by ﬁeld survey. Five soil groups, that is, Arenosols, Regosols, Podzols, Luvisols and Gleysols, combined in three slope classes (ﬂat, undulating and steep) under two different hydromorphic conditions (normal or deﬁcient) were compared based on ﬁve cork oak stand parameters using ANOVA and PCA tests. The results showed a clear inﬂuence of soil type on cork oak growth patterns (cork yield, basal area, number of trees per hectare, crown canopy cover and circumference at breast height). In Arenosols all parameters showed maximum values and, in contrast, in Gleysols were found the minimum values. For instance, the average of the annual cork production for Gleysols (153 kg ha 1 year 1 ) was only 70% of the expected annual cork production of Arenosols (219 kg ha 1 year 1 ) and the average exploited tree density decreased from 56 trees ha 1 in Arenosols to 44 trees ha 1 in Gleysols, for an average exploited tree density of 53 trees ha 1 for the study area. Slope also seems to inﬂuence the cork oak growth patterns, as signiﬁcant statistical differences were found for cork oak growth parameters between slope classes: steep slopes decreased the cork production, the tree size (circumference at breast height) and the tree density. An overall PCA test showed that three main soil groups could be identiﬁed: (i) Arenosols and Podzols; (ii) Regosols and (iii) Luvisols and Gleysols, showing that the former, which could allow the tree root development, have a positive inﬂuence on the cork oak growth. A two-way analysis of variance, for soil type and slope, showed that the cork yield and the exploited tree density are clearly affected by these two factors interaction.
Keywords: cork yield; drainage; montado; Quercus Suber L; slope; Soil; tree density

The relationship between cork oak growth patterns and soil, slope and drainage in a cork oak woodland in Southern Portugal - Costa, Augusta; Madeira, Manuel; Oliveira, Ângelo Carvalho (Forest Ecology and Management, 2008)
The inﬂuence of soil type, slope and drainage on tree growth patterns (density, tree size, crown canopy cover and cork yield) was assessed in a cork oak montado, located in Central-western Portugal, based on a GIS approach followed by ﬁeld survey. Five soil groups, that is, Arenosols, Regosols, Podzols, Luvisols and Gleysols, combined in three slope classes (ﬂat, undulating and steep) under two different hydromorphic conditions (normal or deﬁcient) were compared based on ﬁve cork oak stand parameters using ANOVA and PCA tests. The results showed a clear inﬂuence of soil type on cork oak growth patterns (cork yield, basal area, number of trees per hectare, crown canopy cover and circumference at breast height). In Arenosols all parameters showed maximum values and, in contrast, in Gleysols were found the minimum values. For instance, the average of the annual cork production for Gleysols (153 kg ha 1 year 1 ) was only 70% of the expected annual cork production of Arenosols (219 kg ha 1 year 1 ) and the average exploited tree density decreased from 56 trees ha 1 in Arenosols to 44 trees ha 1 in Gleysols, for an average exploited tree density of 53 trees ha 1 for the study area. Slope also seems to inﬂuence the cork oak growth patterns, as signiﬁcant statistical differences were found for cork oak growth parameters between slope classes: steep slopes decreased the cork production, the tree size (circumference at breast height) and the tree density. An overall PCA test showed that three main soil groups could be identiﬁed: (i) Arenosols and Podzols; (ii) Regosols and (iii) Luvisols and Gleysols, showing that the former, which could allow the tree root development, have a positive inﬂuence on the cork oak growth. A two-way analysis of variance, for soil type and slope, showed that the cork yield and the exploited tree density are clearly affected by these two factors interaction.
Keywords: cork yield; drainage; montado; Quercus Suber L; slope; Soil; tree density

Relationship between net photosynthesis and leaf respiration in Mediterranean evergreen species - Gratani, L; Varone, L; Catoni, R (Photosynthetica, 2008)
The relationship between net photosynthetic (PN) and leaf respiration (R) rates of Quercus ilex, Phillyrea latifolia, Myrtus communis, Arbutus unedo, and Cistus incanus was monitored in the period February 2006 to February 2007. The species investigated had low R and PN during winter, increasing from March to May, when mean air temperature reached 19.2 °C. During the favourable period, C. incanus and A. unedo had a higher mean PN (16.4±2.4 µmol m −2 s −1 ) than P. latifolia, Q. ilex, and M. communis (10.0±1.3 µmol m −2 s −1 ). The highest R (1.89±0.30 µmol m −2 s −1 , mean of the species), associated to a significant PN decrease (62 % of the maximum, mean value of the species), was measured in July (mean R/PN ratio 0.447±0.091). Q10, indicating the respiration sensitivity to short-term temperature increase, was in the range 1.49 to 2.21. Global change might modify R/PN determining differences in dry matter accumulation among the species, and Q. ilex and P. latifolia might be the most favoured species by their ability to maintain sufficiently higher PN and lower R during stress periods.
Keywords: arbutus; cistus; Myrtus; Phillyrea; Q10; Quercus; seasonal course; temperature.

Remote estimation of carbon dioxide uptake by a Mediterranean forest - Garbulsky, Martín F.; Penuelas, Josep; Papale, Dario; Filella, Iolanda (Global Change Biology, 2008)
The estimation of the carbon balance in ecosystems, regions, and the biosphere is currently one of the main concerns in the study of the ecology of global change. Current remote sensing methodologies for estimating gross primary productivity are not satisfactory because they rely too heavily on (i) the availability of climatic data, (ii) the definition of land-use cover, and (iii) the assumptions of the effects of these two factors on the radiation-use efficiency of vegetation (RUE). A new methodology is urgently needed that will actually assess RUE and overcome the problems associated with the capture of fluctuations in carbon absorption in space and over time. Remote sensing techniques such as the widely used reflectance vegetation indices (e.g. NDVI, EVI) allow green plant biomass and therefore plant photosynthetic capacity to be assessed. However, there are vegetation types, such as the Mediterranean forests, with a very low seasonality of these vegetation indices and a high seasonality of carbon uptake. In these cases it is important to detect how much of this capacity is actually realized, which is a much more challenging goal. The photochemical reflectance index (PRI) derived from freely available satellite information (MODIS sensor) presented for a 5-year analysis for a Mediterranean forest a positive relationship with the RUE. Thus, we show that it is possible to estimate RUE and GPP in real time and therefore actual carbon uptake of Mediterranean forests at ecosystem level using the PRI. This conceptual and technological advancement would avoid the need to rely on the sometimes unreliable maximum RUE.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: carbon cycle; CO2 uptake; eddy covariance; Mediterranean forests; MODIS; primary productivity; radiation use efficiency; Remote sensing; Vegetation

Remote estimation of carbon dioxide uptake by a Mediterranean forest - GARBULSKY, MARTÍN F; Penuelas, Josep; Papale, Dario; Filella, Iolanda (Global Change Biology, 2008)
The estimation of the carbon balance in ecosystems, regions, and the biosphere is currently one of the main concerns in the study of the ecology of global change. Current remote sensing methodologies for estimating gross primary productivity are not satisfactory because they rely too heavily on (i) the availability of climatic data, (ii) the definition of land-use cover, and (iii) the assumptions of the effects of these two factors on the radiation-use efficiency of vegetation (RUE). A new methodology is urgently needed that will actually assess RUE and overcome the problems associated with the capture of fluctuations in carbon absorption in space and over time. Remote sensing techniques such as the widely used reflectance vegetation indices (e.g. NDVI, EVI) allow green plant biomass and therefore plant photosynthetic capacity to be assessed. However, there are vegetation types, such as the Mediterranean forests, with a very low seasonality of these vegetation indices and a high seasonality of carbon uptake. In these cases it is important to detect how much of this capacity is actually realized, which is a much more challenging goal. The photochemical reflectance index (PRI) derived from freely available satellite information (MODIS sensor) presented for a 5-year analysis for a Mediterranean forest a positive relationship with the RUE. Thus, we show that it is possible to estimate RUE and GPP in real time and therefore actual carbon uptake of Mediterranean forests at ecosystem level using the PRI. This conceptual and technological advancement would avoid the need to rely on the sometimes unreliable maximum RUE.
Keywords: carbon cycle; CO2 uptake; eddy covariance; Mediterranean forests; MODIS; primary productivity; radiation use efficiency; Remote sensing; Vegetation

The response of epiphytic lichens to air pollution and subsets of ecological predictors: a case study from the Italian Prealps. - Cristofolini, Fabiana; Giordani, Paolo; Gottardini, Elena; Modenesi, Paolo (Environmental pollution (Barking, Essex : 1987), 2008)
We investigated the response of epiphytic lichens to air pollution, against the background of other ecological predictors in a prealpine heterogeneous area, using Non-Parametric Multiplicative Regression (NPMR). The best NPMR model for total lichen diversity according to N environmental predictors at tree level has a cross R(2)=0.709. It includes 10 variables, belonging to three different subsets of factors: two pollution-related factors (distance in meters from the road and from the cement factory); four stand-related (habitat, heat index, LAI and elevation) and four substrate-related factors (inclination, circumference and texture and tree species). Considering separately the effects of each subset on lichen diversity, substrate- and stand-related factors produce good models with similar cross R(2) (0.490 and 0.500, respectively), whereas pollution-related factors produce a model with a lower cross R(2) (0.340). Hence, we provide information to investigate the applicability of lichen biomonitoring to complex heterogeneous areas where standardized protocols are not reliable.
The following values have no corresponding Zotero field: accession-num: 17689161
Keywords: Ecological factors; Lichen diversity; NPMR; Standardized protocol; Toblino

The response of epiphytic lichens to air pollution and subsets of ecological predictors: a case study from the Italian Prealps. - Cristofolini, Fabiana; Giordani, Paolo; Gottardini, Elena; Modenesi, Paolo (Environmental pollution (Barking, Essex : 1987), 2008)
We investigated the response of epiphytic lichens to air pollution, against the background of other ecological predictors in a prealpine heterogeneous area, using Non-Parametric Multiplicative Regression (NPMR). The best NPMR model for total lichen diversity according to N environmental predictors at tree level has a cross R(2)=0.709. It includes 10 variables, belonging to three different subsets of factors: two pollution-related factors (distance in meters from the road and from the cement factory); four stand-related (habitat, heat index, LAI and elevation) and four substrate-related factors (inclination, circumference and texture and tree species). Considering separately the effects of each subset on lichen diversity, substrate- and stand-related factors produce good models with similar cross R(2) (0.490 and 0.500, respectively), whereas pollution-related factors produce a model with a lower cross R(2) (0.340). Hence, we provide information to investigate the applicability of lichen biomonitoring to complex heterogeneous areas where standardized protocols are not reliable.
Keywords: Ecological factors; Lichen diversity; NPMR; Standardized protocol; Toblino

The response of soil erosion and sediment export to land-use change in four areas of Europe: The importance of landscape pattern - Bakker, Martha M; Govers, Gerard; van Doorn, Anne; Quetier, Fabien; Chouvardas, Dimitris; Rounsevell, Mark (Geomorphology, 2008)
The response of erosion and sediment export to past land-use change has been studied in four agricultural areas of Europe. Three of these areas were subject to land abandonment or de-intensification and one to intensification of land-use practices. Erosion and sediment yield were modeled using the WaTEM/SEDEM model, which combines the RUSLE equation with a sediment routing algorithm. Spatial relationships between the RUSLE C-factor (i.e. land-use) and other erosion and sediment exportdetermining factors (slope, soil erodibility and distance to rivers) were investigated, as these account for non-linearity in the response of erosion and sediment export to land-use change. Erosion and sediment export have decreased enormously in the de-intensified areas, but slightly increased in the intensively cultivated area. The spatial pattern of land-use change in relation to other erosion and sediment export-determining factors appears to have a large impact on the response of soil erosion and sediment export to land-use change. That the drivers of abandonment of arable land and erosion coincide indicates that de-intensification leads to a more favourable landscape pattern with respect to reduction of erosion and sediment export. This mechanism applies not only within the study areas, but also among the European study areas where the process of intensification of some areas and de-intensification of others might result in an overall decrease of erosion and sediment yield through time
Keywords: EUROPE; Land-use change; landscape pattern; soil erosion

The response of soil erosion and sediment export to land-use change in four areas of Europe: The importance of landscape pattern - Bakker, Martha M.; Govers, Gerard; van Doorn, Anne; Quetier, Fabien; Chouvardas, Dimitris; Rounsevell, Mark (Geomorphology, 2008)
The response of erosion and sediment export to past land-use change has been studied in four agricultural areas of Europe. Three of these areas were subject to land abandonment or de-intensification and one to intensification of land-use practices. Erosion and sediment yield were modeled using the WaTEM/SEDEM model, which combines the RUSLE equation with a sediment routing algorithm. Spatial relationships between the RUSLE C-factor (i.e. land-use) and other erosion and sediment exportdetermining factors (slope, soil erodibility and distance to rivers) were investigated, as these account for non-linearity in the response of erosion and sediment export to land-use change. Erosion and sediment export have decreased enormously in the de-intensified areas, but slightly increased in the intensively cultivated area. The spatial pattern of land-use change in relation to other erosion and sediment export-determining factors appears to have a large impact on the response of soil erosion and sediment export to land-use change. That the drivers of abandonment of arable land and erosion coincide indicates that de-intensification leads to a more favourable landscape pattern with respect to reduction of erosion and sediment export. This mechanism applies not only within the study areas, but also among the European study areas where the process of intensification of some areas and de-intensification of others might result in an overall decrease of erosion and sediment yield through time
Keywords: EUROPE; Land-use change; landscape pattern; soil erosion

Responses of photosynthesis to high temperatures in oak saplings assessed by chlorophyll-a fluorescence: inter-specific diversity and temperature-induced plasticity - Daas, C; Montpied, P; Hanchi, B; Dreyer, E (Annals of forest science, 2008)
• The sensitivity of photosynthesis to high temperature was investigated in greenhouse-grown saplings of three Mediterranean (Quercus canariensis Willd., Q. coccifera L. and Q. suber L.) and two temperate European oak species (Q. robur L. and Q. petraea Matt. Liebl.). The sensitivity to high temperature was inferred from F0T curves producing the critical temperature (Tc ) at which a rapid rise in ground chlorophyll a ﬂuorescence (F0) occurs. Tc is known to acclimate to moderately increased ambient temperature by displaying signiﬁcant increases. • We ﬁrst checked whether acclimation of Tc was paralleled by an increase in optimal temperature for light driven electron ﬂux (Topt ,), recorded by measuring quantum yield of photochemistry under saturating CO2 and moderate irradiance. Saplings of Q. suber and Q. canariensis were submitted to four, ﬁve days long ambient temperature steps (15, 25, 35 and 15 ◦ C again). Tc was usually largely above 45 ◦ C while Topt was around 30–35 ◦ C. Both increased with ambient temperature in the two species, and decreased again when temperature returned to the initial values. This recovery was nevertheless not complete after a week at 15 ◦ C. • A second experiment tested whether the plasticity of Tc was of the same extent in the ﬁve species. A signiﬁcant increase of Tc followed by a decrease was detected in all species. Only small inter-speciﬁc diﬀerences were detected in Tc , and temperature induced plasticity was similar in the diﬀerent species: Tc increased by about 4–5 ◦ C while ambient temperature was increased from 15 to 35 ◦ C. Mediterranean and European oaks did not diﬀer in this respect. • This result does not support the hypothesis that oak species from warmer regions would display a larger plasticity of Tc in response to increasing temperatures.
Keywords: optimal temperature; Photochemistry; quantum yield; Quercus canariensis; Quercus coccifera; Quercus petraea; Quercus robur; Quercus suber

Responses of photosynthesis to high temperatures in oak saplings assessed by chlorophyll-a fluorescence: inter-specific diversity and temperature-induced plasticity - Daas, C.; Montpied, P.; Hanchi, B.; Dreyer, E. (Annals of forest science, 2008)
• The sensitivity of photosynthesis to high temperature was investigated in greenhouse-grown saplings of three Mediterranean (Quercus canariensis Willd., Q. coccifera L. and Q. suber L.) and two temperate European oak species (Q. robur L. and Q. petraea Matt. Liebl.). The sensitivity to high temperature was inferred from F0T curves producing the critical temperature (Tc ) at which a rapid rise in ground chlorophyll a ﬂuorescence (F0) occurs. Tc is known to acclimate to moderately increased ambient temperature by displaying signiﬁcant increases. • We ﬁrst checked whether acclimation of Tc was paralleled by an increase in optimal temperature for light driven electron ﬂux (Topt ,), recorded by measuring quantum yield of photochemistry under saturating CO2 and moderate irradiance. Saplings of Q. suber and Q. canariensis were submitted to four, ﬁve days long ambient temperature steps (15, 25, 35 and 15 ◦ C again). Tc was usually largely above 45 ◦ C while Topt was around 30–35 ◦ C. Both increased with ambient temperature in the two species, and decreased again when temperature returned to the initial values. This recovery was nevertheless not complete after a week at 15 ◦ C. • A second experiment tested whether the plasticity of Tc was of the same extent in the ﬁve species. A signiﬁcant increase of Tc followed by a decrease was detected in all species. Only small inter-speciﬁc diﬀerences were detected in Tc , and temperature induced plasticity was similar in the diﬀerent species: Tc increased by about 4–5 ◦ C while ambient temperature was increased from 15 to 35 ◦ C. Mediterranean and European oaks did not diﬀer in this respect. • This result does not support the hypothesis that oak species from warmer regions would display a larger plasticity of Tc in response to increasing temperatures.
Keywords: optimal temperature; Photochemistry; quantum yield; Quercus canariensis; Quercus coccifera; Quercus petraea; Quercus robur; Quercus suber

Responses of Photosynthetic and Defence Systems to High Temperature Stress in Quercus suber L Seedlings Grown under Elevated CO2 - FARIA, T.; Vaz, M.; Schwanz, P.; PolIe, A. (Plant biology (Stuttgart, Germany), 2008)
Growth in elevated CO2 led to an increase in biomass production per plant as a result of enhanced carbon uptake and lower rates of respiration, compared to ambient C02-grown plants. No down-regulation of photosynthesis was found after six months of growth under elevated CO2. Photosynthetic rates at 15°C or 35°C were also higher in elevated than in ambient C02-grown plants, when measured at their respective CO2 growth condition. Stomata of elevated C02-grown plants were less responsive to temperature as compared to ambient CO2 plants. The after effect of a heat-shock treatment (4 h at 45°C in a chamber with 80% of relative humidity and 800—1000 tmol rn2 photon flux density) on Amax was less in elevated than in ambient C02-grown plants. At the photochemical level, the negative effect of the heat-shock treatment was slightly more pronounced in ambient than in elevated CO2-grown plants. A greater tolerance to oxidative stress caused by high temperatures in elevated C02-grown plants, in comparison to ambient CO2 plants, is suggested by the increase in superoxide dismutase activity, after 1 h at 45°C, as well as its relatively high activity after 2 and 4 h of the heat shock in the elevated C02-grown plants in contrast with the decrease to residual levels of superoxide dismutase activity in ambient C02-grown plants immediately after 1 h at 45°C. The observed increase in catalase after 1 h at 45°C in both ambient and elevated C02-grown plants, can be ascribed to the higher rates of photorespiration and respiration under this high temperature.
Keywords: catalase; Elevated CO2; photosynthesis; Quercus suber L.; superoxide dismutase; Temperature

Responses of Photosynthetic and Defence Systems to High Temperature Stress in Quercus suber L Seedlings Grown under Elevated CO2 - Faria, T; Vaz, M; Schwanz, P; PolIe, A (Plant biology (Stuttgart, Germany), 2008)
Growth in elevated CO2 led to an increase in biomass production per plant as a result of enhanced carbon uptake and lower rates of respiration, compared to ambient C02-grown plants. No down-regulation of photosynthesis was found after six months of growth under elevated CO2. Photosynthetic rates at 15°C or 35°C were also higher in elevated than in ambient C02-grown plants, when measured at their respective CO2 growth condition. Stomata of elevated C02-grown plants were less responsive to temperature as compared to ambient CO2 plants. The after effect of a heat-shock treatment (4 h at 45°C in a chamber with 80% of relative humidity and 800—1000 tmol rn2 photon flux density) on Amax was less in elevated than in ambient C02-grown plants. At the photochemical level, the negative effect of the heat-shock treatment was slightly more pronounced in ambient than in elevated CO2-grown plants. A greater tolerance to oxidative stress caused by high temperatures in elevated C02-grown plants, in comparison to ambient CO2 plants, is suggested by the increase in superoxide dismutase activity, after 1 h at 45°C, as well as its relatively high activity after 2 and 4 h of the heat shock in the elevated C02-grown plants in contrast with the decrease to residual levels of superoxide dismutase activity in ambient C02-grown plants immediately after 1 h at 45°C. The observed increase in catalase after 1 h at 45°C in both ambient and elevated C02-grown plants, can be ascribed to the higher rates of photorespiration and respiration under this high temperature.
Keywords: catalase; Elevated CO2; photosynthesis; Quercus suber L.; superoxide dismutase; Temperature

Responses of the aleppo pine (Pinus halepensis Mill.) and the holm oak (Quercus ilex L. subsp. ballota (Desf.) Samp.) to the collection of overland runoffs through minicatchments in different Mediterranean environments - DE SIMÓN NAVARRETE, E.; Ripoll Morales, M. A.; Fernández Ondoño, E.; Navarro Reyes, F. B.; Jiménez Morales, M. N.; Gallego Teruel, E. (Forest Systems; Vol 15, No 2 (2006), 2008)
Water is one of the most limiting factors in the forestation of Mediterranean areas, so that the survival and development of these areas is always connected to the availability of water resources. The aim of this study is to assess the efficiency of a series of hydraulic structures linked to land preparation, called minicatchments, as runoff collectors meant to increase water availability in the forestation. In order to do so, the amount of overland runoff reaching every seedling, as well as the survival of the reforestation in four places with different climatic and edaphic characteristics have been assessed. Results obtained show how water availability depends both on the amount of water reaching the bank and on the physical properties of the land. The areas that have normally been considered more difficult to restore due to a de-structured profile, to the presence of superficial physical crusts and to a scarce vegetal cover are the ones showing a better response to the technique of runoff collection trough minicatchments.
Keywords: minicatchment; overland runoff; Soil moisture

Responses of the aleppo pine (Pinus halepensis Mill.) and the holm oak (Quercus ilex L. subsp. ballota (Desf.) Samp.) to the collection of overland runoffs through minicatchments in different Mediterranean environments - DE SIMÓN NAVARRETE, E; Ripoll Morales, M A; Fernández Ondoño, E; Navarro Reyes, F B; Jiménez Morales, M N; Gallego Teruel, E (Forest Systems; Vol 15, No 2 (2006), 2008)
Water is one of the most limiting factors in the forestation of Mediterranean areas, so that the survival and development of these areas is always connected to the availability of water resources. The aim of this study is to assess the efficiency of a series of hydraulic structures linked to land preparation, called minicatchments, as runoff collectors meant to increase water availability in the forestation. In order to do so, the amount of overland runoff reaching every seedling, as well as the survival of the reforestation in four places with different climatic and edaphic characteristics have been assessed. Results obtained show how water availability depends both on the amount of water reaching the bank and on the physical properties of the land. The areas that have normally been considered more difficult to restore due to a de-structured profile, to the presence of superficial physical crusts and to a scarce vegetal cover are the ones showing a better response to the technique of runoff collection trough minicatchments.
Keywords: minicatchment; overland runoff; Soil moisture

The role of temporal shrub encroachment for the maintenance of Spanish holm oak Quercus ilex dehesas - Ramírez, José Alberto; Díaz, Mario (Forest Ecology and Management, 2008)
Dehesas are man-made systems composed by evergreen oaks (Quercus ilex and Quercus suber) scattered over a grassland understorey. They cover about 3.1 million ha in the southwest of the Iberian Peninsula and are to be preserved under the EU Habitats Directive due to the high levels of plant and animal diversity they maintain. The main current threat to long-term dehesa farming is a chronic absence of natural tree regeneration.We test whether dehesa abandonment would promote natural regeneration, how size structure of tree populations change after abandonment, and whether shrub encroachment would enhance seedling recruitment by measuring the size structure of mature tree populations, shrub cover and seedling density in 17 dehesa farms of known date of abandonment. Size structures were approximately bell-shaped in farms abandoned less than 16 years ago, progressively approaching afterwards the inverse J-shaped distribution typical from holm oak forests. Proportions of young mature trees changed with age of abandonment according to a logistic growth function. Proportions typical from forests (70–80%) were reached 30 years after abandonment, whereas balanced numbers of young and old trees were reached 20–25 years after abandonment. Short-term seedling recruitment was not related to age of abandonment or to covers of most dominant shrubs and was positively related to cover of mature trees and of Cytisus multiflorus, a nurse shrub for holm oak seedlings. Synthesis and applications: Conservation of dehesas and their associated biodiversity values should be based on financing temporal abandonment of productive dehesa farming for 20 years, keeping land in good agricultural condition by re-opening the encroached plots after tree recruitment (i.e. rotational set-aside). The proposed measure has the additional advantages of easy monitoring and straightforward evaluation of its effectiveness.
Keywords: Dehesa; Quercus ilex; Regeneration; rotational set-aside; Shrub cover; Sustainability

The role of temporal shrub encroachment for the maintenance of Spanish holm oak Quercus ilex dehesas - Ramírez, José Alberto; Díaz, Mario (Forest Ecology and Management, 2008)
Dehesas are man-made systems composed by evergreen oaks (Quercus ilex and Quercus suber) scattered over a grassland understorey. They cover about 3.1 million ha in the southwest of the Iberian Peninsula and are to be preserved under the EU Habitats Directive due to the high levels of plant and animal diversity they maintain. The main current threat to long-term dehesa farming is a chronic absence of natural tree regeneration.We test whether dehesa abandonment would promote natural regeneration, how size structure of tree populations change after abandonment, and whether shrub encroachment would enhance seedling recruitment by measuring the size structure of mature tree populations, shrub cover and seedling density in 17 dehesa farms of known date of abandonment. Size structures were approximately bell-shaped in farms abandoned less than 16 years ago, progressively approaching afterwards the inverse J-shaped distribution typical from holm oak forests. Proportions of young mature trees changed with age of abandonment according to a logistic growth function. Proportions typical from forests (70–80%) were reached 30 years after abandonment, whereas balanced numbers of young and old trees were reached 20–25 years after abandonment. Short-term seedling recruitment was not related to age of abandonment or to covers of most dominant shrubs and was positively related to cover of mature trees and of Cytisus multiflorus, a nurse shrub for holm oak seedlings. Synthesis and applications: Conservation of dehesas and their associated biodiversity values should be based on financing temporal abandonment of productive dehesa farming for 20 years, keeping land in good agricultural condition by re-opening the encroached plots after tree recruitment (i.e. rotational set-aside). The proposed measure has the additional advantages of easy monitoring and straightforward evaluation of its effectiveness.
Keywords: Dehesa; Quercus ilex; Regeneration; rotational set-aside; Shrub cover; Sustainability

Seasonal and annual variation of carbon exchange in an evergreen Mediterranean forest in southern France - ALLARD, V.; OURCIVAL, J. M.; Rambal, S.; JOFFRE, R.; Rocheteau, A. (Global Change Biology, 2008)
We present 9 years of eddy covariance measurements made over an evergreen Mediterranean forest in southern France. The goal of this study was to quantify the different components of the carbon (C) cycle, gross primary production (GPP) and ecosystem respiration (Reco), and to assess the effects of climatic variables on these fluxes and on the net ecosystem exchange of carbon dioxide. The Puéchabon forest acted as a net C sink of −254 g C m−2 yr−1, with a GPP of 1275 g C m−2 yr−1 and a Reco of 1021 g C m−2 yr−1. On average, 83% of the net annual C sink occurred between March and June. The effects of exceptional events such the insect-induced partial canopy defoliation that occurred in spring 2005, and the spring droughts of 2005 and 2006 are discussed. A high interannual variability of ecosystem C fluxes during summer and autumn was observed but the resulting effect on the annual net C budget was moderate. Increased severity and/or duration of summer drought under climate change do not appear to have the potential to negatively impact the average C budget of this ecosystem. On the contrary, factors affecting ecosystem functioning (drought and/or defoliation) during March–June period may reduce dramatically the annual C balance of evergreen Mediterranean forests.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: CO2 fluxes; eddy covariance; Mediterranean ecosystem; Quercus ilex

Seasonal and annual variation of carbon exchange in an evergreen Mediterranean forest in southern France - ALLARD, V; Ourcival, J M; Rambal, S; Joffre, R; Rocheteau, A (Global Change Biology, 2008)
We present 9 years of eddy covariance measurements made over an evergreen Mediterranean forest in southern France. The goal of this study was to quantify the different components of the carbon (C) cycle, gross primary production (GPP) and ecosystem respiration (Reco), and to assess the effects of climatic variables on these fluxes and on the net ecosystem exchange of carbon dioxide. The Puéchabon forest acted as a net C sink of −254 g C m−2 yr−1, with a GPP of 1275 g C m−2 yr−1 and a Reco of 1021 g C m−2 yr−1. On average, 83% of the net annual C sink occurred between March and June. The effects of exceptional events such the insect-induced partial canopy defoliation that occurred in spring 2005, and the spring droughts of 2005 and 2006 are discussed. A high interannual variability of ecosystem C fluxes during summer and autumn was observed but the resulting effect on the annual net C budget was moderate. Increased severity and/or duration of summer drought under climate change do not appear to have the potential to negatively impact the average C budget of this ecosystem. On the contrary, factors affecting ecosystem functioning (drought and/or defoliation) during March–June period may reduce dramatically the annual C balance of evergreen Mediterranean forests.
Keywords: CO2 fluxes; eddy covariance; Mediterranean ecosystem; Quercus ilex

Seasonal variability of dry matter content and its relationship with shoot growth and nonstructural carbohydrates - Palacio, Sara; Milla, Rubén; Albuixech, Jorge; Pérez-Rontomé, Carmen; Camarero, Jesús Julio; Maestro, Melchor; Montserrat-Martí, Gabriel (New Phytologist, 2008)
* • This study assesses how different phases of shoot growth underlie seasonal change in leaf and stem dry matter content (LDMC and SDMC, respectively) of 12 woody Mediterranean species. The relationship between LDMC and nonstructural carbohydrate (NSC) concentrations is also explored and the seasonal vs interspecies variability of LDMC compared. * • LDMC, SDMC and shoot elongation rate (SER) were measured on a monthly basis for a minimum of 12 months. Bud growth rate (BGR) and NSC concentrations were also assessed in several of the study species. * • LDMC and SDMC decreased during shoot elongation in spring and increased in summer, showing a significant negative correlation with SER, but were unrelated to BGR. Half of the species analysed showed a positive relationship between LDMC and NSC. Seasonal fluctuations of LDMC within species were higher than interspecies differences, and species ranking was significantly affected by the month of sampling, except during winter months. * • Seasonal changes in LDMC and SDMC are mainly related to shoot elongation phenology, and NSC sink–source relationships between old and growing organs can explain this relationship in some species. Owing to the high seasonal variability in LDMC, it is recommended that samples for comparative purposes should be collected as close to the winter as possible.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd accession-num: 18643937
Keywords: Carbohydrate Metabolism; functional classifications; leaf dry matter content (LDMC); leaf traits; leaf water status; Mediterranean; Phenology; Plant Development; Plant Leaves; Plant Leaves: growth & development; Plant Leaves: metabolism; Plant Shoots; Plant Shoots: growth & development; Plant Shoots: metabolism; Plant Stems; Plant Stems: growth & development; Plant Stems: metabolism; Plants; Plants: metabolism; Seasons; shoot growth; Species Specificity

Seasonal variability of dry matter content and its relationship with shoot growth and nonstructural carbohydrates - Palacio, Sara; Milla, Rubén; Albuixech, Jorge; Pérez-Rontomé, Carmen; Camarero, Jesús Julio; Maestro, Melchor; Montserrat-Martí, Gabriel (New Phytologist, 2008)
* • This study assesses how different phases of shoot growth underlie seasonal change in leaf and stem dry matter content (LDMC and SDMC, respectively) of 12 woody Mediterranean species. The relationship between LDMC and nonstructural carbohydrate (NSC) concentrations is also explored and the seasonal vs interspecies variability of LDMC compared. * • LDMC, SDMC and shoot elongation rate (SER) were measured on a monthly basis for a minimum of 12 months. Bud growth rate (BGR) and NSC concentrations were also assessed in several of the study species. * • LDMC and SDMC decreased during shoot elongation in spring and increased in summer, showing a significant negative correlation with SER, but were unrelated to BGR. Half of the species analysed showed a positive relationship between LDMC and NSC. Seasonal fluctuations of LDMC within species were higher than interspecies differences, and species ranking was significantly affected by the month of sampling, except during winter months. * • Seasonal changes in LDMC and SDMC are mainly related to shoot elongation phenology, and NSC sink–source relationships between old and growing organs can explain this relationship in some species. Owing to the high seasonal variability in LDMC, it is recommended that samples for comparative purposes should be collected as close to the winter as possible.
Keywords: Carbohydrate Metabolism; functional classifications; leaf dry matter content (LDMC); leaf traits; leaf water status; Mediterranean; Phenology; Plant Development; Plant Leaves; Plant Leaves: growth & development; Plant Leaves: metabolism; Plant Shoots; Plant Shoots: growth & development; Plant Shoots: metabolism; Plant Stems; Plant Stems: growth & development; Plant Stems: metabolism; Plants; Plants: metabolism; Seasons; shoot growth; Species Specificity

Seed bank composition and above-ground vegetation in response to grazing in sub-Mediterranean oak forests (NW Greece) - Chaideftou, Evgenia; Thanos, Costas A.; Bergmeier, Erwin; Kallimanis, Athanasios; Dimopoulos, Panayotis (Plant Ecology, 2008)
We investigate the persistent soil seed bank composition and its relation to the above-ground ﬂora of grazed and non-grazed sub-Mediterranean deciduous oak forests of NW Greece. Twenty-eight taxa were recorded in the soil seed bank and 83 taxa (70 taxa in plots of seed bank sampling) in the aboveground vegetation. The dominant tree species and many woodland species found in the above-ground vegetation were absent from the soil seed bank. Similarity between the soil seed bank and the aboveground vegetation decreased with grazing, and grazing led to a decrease of species richness in above-ground vegetation and soil seed bank. Beta diversity of vegetation among grazed and among nongrazed plots did not differ, but was signiﬁcantly higher between grazed and non-grazed areas. Beta diversity of the soil seed bank declined with grazing. When applying classiﬁcation tree and logistic regression analyses, non-grazed forest sites are clearly differentiated by the presence of Phillyrea latifolia, Euphorbia amygdaloides and Brachypodium sylvaticum. PCA ordination of above-ground species composition reﬂected a gradient from sites grazed by ruminants to non-grazed sites, but no clear structure was detected in the seed bank.
Keywords: á ruminants; Deciduous oak forests; deciduous oak forests á; grazing á browsing á; Grazing Browsing; greece; greece á wild boar; Ruminants; Soil seed bank; soil seed bank á; Wild boar; Wood pasture; wood pasture á

Seed bank composition and above-ground vegetation in response to grazing in sub-Mediterranean oak forests (NW Greece) - Chaideftou, Evgenia; Thanos, Costas a; Bergmeier, Erwin; Kallimanis, Athanasios; Dimopoulos, Panayotis (Plant Ecology, 2008)
We investigate the persistent soil seed bank composition and its relation to the above-ground ﬂora of grazed and non-grazed sub-Mediterranean deciduous oak forests of NW Greece. Twenty-eight taxa were recorded in the soil seed bank and 83 taxa (70 taxa in plots of seed bank sampling) in the aboveground vegetation. The dominant tree species and many woodland species found in the above-ground vegetation were absent from the soil seed bank. Similarity between the soil seed bank and the aboveground vegetation decreased with grazing, and grazing led to a decrease of species richness in above-ground vegetation and soil seed bank. Beta diversity of vegetation among grazed and among nongrazed plots did not differ, but was signiﬁcantly higher between grazed and non-grazed areas. Beta diversity of the soil seed bank declined with grazing. When applying classiﬁcation tree and logistic regression analyses, non-grazed forest sites are clearly differentiated by the presence of Phillyrea latifolia, Euphorbia amygdaloides and Brachypodium sylvaticum. PCA ordination of above-ground species composition reﬂected a gradient from sites grazed by ruminants to non-grazed sites, but no clear structure was detected in the seed bank.
Keywords: á ruminants; Deciduous oak forests; deciduous oak forests á; grazing á browsing á; Grazing Browsing; greece; greece á wild boar; Ruminants; Soil seed bank; soil seed bank á; Wild boar; Wood pasture; wood pasture á

Seed removal in two coexisting oak species: ecological consequences of seed size, plant cover and seed-drop timing - Pérez-Ramos, Ignacio M; Urbieta, Itziar R; Marañón, Teodoro; Zavala, M A; Kobe, Richard K (Oikos, 2008)
Seed predation and dispersal can critically influence plant community structure and dynamics. Inter-specific differences arising at these early stages play a crucial role on tree recruitment patterns, which in turn could influence forest dynamics and species segregation in heterogeneous environments such as Mediterranean forests. We investigated removal rates from acorns set onto the ground in two coexisting Mediterranean oak species –Quercus canariensis and Q. suber– in southern Spain. We developed maximum likelihood estimators to investigate the main factors controlling probabilities of seed removal and to describe species-specific functional responses. To account for inter-specific differences in seed-drop timing, two experiments were established: a simultaneous exposure of acorns of the two species (synchronous experiments) and a seed exposure following their natural seed-drop phenology (diachronic experiments). A total of 1536 acorns were experimentally distributed along a wide and natural gradient of plant cover, and removal was periodically monitored for three months at two consecutive years (with contrasting differences in seed production and thus seed availability on the ground). The probability of seed removal increased with plant cover (leaf area index, LAI) for the two oak species. Inter-specific differences in acorn removal were higher in open areas and disappeared in closed microhabitats, especially during a non-mast year. Despite later seed-drop, Q. suber acorns were removed faster and at a higher proportion than those of Q. canariensis. The higher probability of seed removal for this species could be attributed to its larger seed size compared to Q. canariensis, as inter-specific differences were less pronounced when similar sized acorns were exposed. Inter-specific differences in seed removal, arising from seed size variability and microsite heterogeneity, could be of paramount importance in oak species niche separation, driving stand dynamics and composition along environmental gradients.
Keywords: plant cover (voyant); Quercus canariensis; Quercus suber; Seed removal; Seed size

Seed removal in two coexisting oak species: ecological consequences of seed size, plant cover and seed-drop timing - Pérez-Ramos, Ignacio M.; Urbieta, Itziar R.; Marañón, Teodoro; Zavala, M. A.; Kobe, Richard K. (Oikos, 2008)
Seed predation and dispersal can critically influence plant community structure and dynamics. Inter-specific differences arising at these early stages play a crucial role on tree recruitment patterns, which in turn could influence forest dynamics and species segregation in heterogeneous environments such as Mediterranean forests. We investigated removal rates from acorns set onto the ground in two coexisting Mediterranean oak species –Quercus canariensis and Q. suber– in southern Spain. We developed maximum likelihood estimators to investigate the main factors controlling probabilities of seed removal and to describe species-specific functional responses. To account for inter-specific differences in seed-drop timing, two experiments were established: a simultaneous exposure of acorns of the two species (synchronous experiments) and a seed exposure following their natural seed-drop phenology (diachronic experiments). A total of 1536 acorns were experimentally distributed along a wide and natural gradient of plant cover, and removal was periodically monitored for three months at two consecutive years (with contrasting differences in seed production and thus seed availability on the ground). The probability of seed removal increased with plant cover (leaf area index, LAI) for the two oak species. Inter-specific differences in acorn removal were higher in open areas and disappeared in closed microhabitats, especially during a non-mast year. Despite later seed-drop, Q. suber acorns were removed faster and at a higher proportion than those of Q. canariensis. The higher probability of seed removal for this species could be attributed to its larger seed size compared to Q. canariensis, as inter-specific differences were less pronounced when similar sized acorns were exposed. Inter-specific differences in seed removal, arising from seed size variability and microsite heterogeneity, could be of paramount importance in oak species niche separation, driving stand dynamics and composition along environmental gradients.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: plant cover (voyant); Quercus canariensis; Quercus suber; Seed removal; Seed size

Sheep farms in the Spanish rangelands (dehesas): Typologies according to livestock management and economic indicators - Gaspar, P; Escribano, M; Mesías, F J; Ledesma, a. Rodriguez De; Pulido, F (Small Ruminant Research, 2008)
Forty-six dehesa sheep farms of Extremadura (SW Spain) were analyzed on the basis of previously determined technical and economic indicators. A principal component analysis gave ﬁve principal components – related to intensiﬁcation, proﬁtability, and livestock mix – that characterized the farms. Using multivariate techniques based on these factors, a farm typology was established with six categories—three of sheep alone at different levels of intensiﬁcation, and three of sheep in combination with beef cattle or Iberian pig. This typology enabled homogeneous groups of farms to be considered for possible administrative actions relating to their optimal dimensions and stocking rates
Keywords: Dehesa; Farm typology; Principal component analysis; Sheep; technical and economic management

Sheep farms in the Spanish rangelands (dehesas): Typologies according to livestock management and economic indicators - Gaspar, P.; Escribano, M.; Mesías, F. J.; Ledesma, a Rodriguez De; Pulido, F. (Small Ruminant Research, 2008)
Forty-six dehesa sheep farms of Extremadura (SW Spain) were analyzed on the basis of previously determined technical and economic indicators. A principal component analysis gave ﬁve principal components – related to intensiﬁcation, proﬁtability, and livestock mix – that characterized the farms. Using multivariate techniques based on these factors, a farm typology was established with six categories—three of sheep alone at different levels of intensiﬁcation, and three of sheep in combination with beef cattle or Iberian pig. This typology enabled homogeneous groups of farms to be considered for possible administrative actions relating to their optimal dimensions and stocking rates
Keywords: Dehesa; Farm typology; Principal component analysis; Sheep; technical and economic management

Silviculture and Carbon Sequestration in Mediterranean Oak Forests - Cañellas, I; Sanchez-Gonzalez, M; Bogino, S M; Adame, P; Herrero, C; Roig, S; Paulo, J A; Bravo, F (Managing Forest Ecosystems: The Challenge of Climate Change,, 2008)
The Kyoto Protocol requires every industrialized country to have a transparent and verifiable method for estimating the size and evolution of the carbon stored in forest ecosystems. The intergovernmental panel on climate change (IPCC, 2007) predicts the evolution of the stock over the first commitment period (2008–2012) using the “bottom-up approach”. This approach is based on the use of data from national or regional forest inventories. The biomass of living trees including their dead parts comprises the main carbon pool in forest ecosystems along with the biomass of understorey plants, litter, woody debris and soil organic matter (Pignard et al., 2004). The objective of this chapter is to present some of the studies currently being carried out in Spain and Portugal which are concerned with the possibility of estimating the amount of carbon fixed by two of the main oak species in the Iberian Peninsula; rebollo oak (Quercus pyrenaica Willd.) and cork oak (Quercus suber L.). Three different methodological approaches have been used. The first approach is to use growth models to evaluate the carbon sequestration in both cork and wood over the life of a cork oak plantation. This approach has been applied both for Spain and Portugal. The second approach involves using a yield table as a tool to estimate the carbon sequestration in Quercus pyrenaica forests based on Spanish National Forest Inventories. In a third approach, data from a network of plots is used to estimate the carbon sequestration in pure and mixed Quercus pyrenaica forests. The application of these different methodologies would allow us to forecast and improve the carbon sequestration in oak forests as well as increasing our understanding of their dynamics.
Keywords: biomass; carbon stock; Kyoto protocol; Portugal; Spain

Silviculture and Carbon Sequestration in Mediterranean Oak Forests - Cañellas, I.; Sánchez-González, M.; Bogino, S. M.; Adame, P.; Herrero, C.; ROIG, S.; Paulo, J. A.; Bravo, F. (Managing Forest Ecosystems: The Challenge of Climate Change,, 2008)
The Kyoto Protocol requires every industrialized country to have a transparent and verifiable method for estimating the size and evolution of the carbon stored in forest ecosystems. The intergovernmental panel on climate change (IPCC, 2007) predicts the evolution of the stock over the first commitment period (2008–2012) using the “bottom-up approach”. This approach is based on the use of data from national or regional forest inventories. The biomass of living trees including their dead parts comprises the main carbon pool in forest ecosystems along with the biomass of understorey plants, litter, woody debris and soil organic matter (Pignard et al., 2004). The objective of this chapter is to present some of the studies currently being carried out in Spain and Portugal which are concerned with the possibility of estimating the amount of carbon fixed by two of the main oak species in the Iberian Peninsula; rebollo oak (Quercus pyrenaica Willd.) and cork oak (Quercus suber L.). Three different methodological approaches have been used. The first approach is to use growth models to evaluate the carbon sequestration in both cork and wood over the life of a cork oak plantation. This approach has been applied both for Spain and Portugal. The second approach involves using a yield table as a tool to estimate the carbon sequestration in Quercus pyrenaica forests based on Spanish National Forest Inventories. In a third approach, data from a network of plots is used to estimate the carbon sequestration in pure and mixed Quercus pyrenaica forests. The application of these different methodologies would allow us to forecast and improve the carbon sequestration in oak forests as well as increasing our understanding of their dynamics.
The following values have no corresponding Zotero field: periodical: Managing Forest Ecosystems: The Challenge of Climate Change, electronic-resource-num: 10.1007/978-1-4020-8343-3
Keywords: biomass; carbon stock; Kyoto protocol; Portugal; Spain

Silvopastoral systems in Portugal: Current status and future prospects - Castro, M (Agroforestry in Europe: Current Status and Future Prospects., 2008)
Portugal has a high diversity of agroforestry systems like other Mediterranean countries. This is the result of the Mediterranean climate, great variability of bioclimatic conditions, a long history of land use, and a marked variation in land tenure between north and south of the country. Four major silvopastoral systems are described: two classically Mediterranean – montado and Olive tree system, and two typically of the transitional environment between Mediterranean and Temperate conditions – Pyrenean oak and Chestnut systems. Some products of traditional agroforestry systems such as charcoal, organic manure, livestock production and others have become less valuable with the socio-economic transformation of the 1960s. These systems have been declining from approximately 1950 onwards. Currently, the focus on sustainable agriculture, with greater emphasis on nature and landscape conservation, has meant that environmental values now represent new opportunities for income generation from these systems. A better understanding of traditional agroforestry systems is needed for the formulation of a specific European policy that will preserve European landscapes. This paper looks at the future potential for silvopastoral systems in Portugal based on current status.
Keywords: chestnut systems; montado; olive tree system; Portugal; pyrenean oak system

Silvopastoral systems in Portugal: Current status and future prospects - Castro, M. (Agroforestry in Europe: Current Status and Future Prospects., 2008)
Portugal has a high diversity of agroforestry systems like other Mediterranean countries. This is the result of the Mediterranean climate, great variability of bioclimatic conditions, a long history of land use, and a marked variation in land tenure between north and south of the country. Four major silvopastoral systems are described: two classically Mediterranean – montado and Olive tree system, and two typically of the transitional environment between Mediterranean and Temperate conditions – Pyrenean oak and Chestnut systems. Some products of traditional agroforestry systems such as charcoal, organic manure, livestock production and others have become less valuable with the socio-economic transformation of the 1960s. These systems have been declining from approximately 1950 onwards. Currently, the focus on sustainable agriculture, with greater emphasis on nature and landscape conservation, has meant that environmental values now represent new opportunities for income generation from these systems. A better understanding of traditional agroforestry systems is needed for the formulation of a specific European policy that will preserve European landscapes. This paper looks at the future potential for silvopastoral systems in Portugal based on current status.
The following values have no corresponding Zotero field: periodical: Agroforestry in Europe: Current Status and Future Prospects.
Keywords: chestnut systems; montado; olive tree system; Portugal; pyrenean oak system

Sistema para a Predição do Crescimento da Cortiça - Almeida, Alice; Tomé, Margarida (Silva Lusitana, 2008)
. Cork growth modelling was based on two models: cork growth model for complete rings and a model for total cork thickness prediction. The cork growth model was developed using data from 189 cork samples taken at breast height. Four biological growth functions were considered using their formulation as difference equations. The evaluation of the fitting and predictive ability of the models was based on model efficiency and on several statistics computed with the press residuals, complemented with graphical analysis to assess the regression assumptions. The model selected - Lundqvist-A - can be used to predict cork thickness in complete rings at any year of the cork rotation. The model for the prediction of total cork thickness is used to predict total cork thickness from the thickness in complete rings
Keywords: accumulated cork thickness in complete rings; cork growth; growth models; prediction; total cork thickness prediction

Sistema para a Predição do Crescimento da Cortiça - Almeida, Alice; Tomé, Margarida (Silva Lusitana, 2008)
. Cork growth modelling was based on two models: cork growth model for complete rings and a model for total cork thickness prediction. The cork growth model was developed using data from 189 cork samples taken at breast height. Four biological growth functions were considered using their formulation as difference equations. The evaluation of the fitting and predictive ability of the models was based on model efficiency and on several statistics computed with the press residuals, complemented with graphical analysis to assess the regression assumptions. The model selected - Lundqvist-A - can be used to predict cork thickness in complete rings at any year of the cork rotation. The model for the prediction of total cork thickness is used to predict total cork thickness from the thickness in complete rings
The following values have no corresponding Zotero field: publisher: scielopt
Keywords: accumulated cork thickness in complete rings; cork growth; growth models; prediction; total cork thickness prediction

Soil water content and emergence time control seedling establishment in three co-occurring Mediterranean oak species - Urbieta, Itziar R.; Pérez-Ramos, Ignacio M.; Zavala, Miguel A.; Marañón, Teodoro; Kobe, Richard K. (Canadian Journal of Forest Research, 2008)
Tree species can differ in their responses to resource availability during the critical phase of establishment, which could influence forest dynamics. In Mediterranean forests, most of the attention has focused on the effects of shade and summer drought on seedling survival, but little is known about the effect of autumn to spring rains on earlier stages of recruitment. A sowing experiment was set up along natural light and water gradients with three co-occurring oak species (Quercus suber L. (cork oak), Quercus canariensis Willd. (Algerian oak), and Quercus pyrenaica Willd. (Pyrenean oak)) that show limited natural regeneration in southern Spain. Recruitment stages were monitored for 1 year. Models of seed germination, seedling emergence, and seedling survival as well as of overall recruitment patterns were developed as functions of light, soil moisture, and soil compaction. The influence of intraspecific variation in seed mass and emergence time were also tested. Excess soil water levels during the winter reduced germination and emergence and lengthened time to emergence (in waterlogged open areas), which in turn decreased seedling survival during the dry season. Seedlings from larger seeds were more likely to germinate and emerge. The results suggest that temporal and spatial variability of soil water content, mediated by emergence time and seed size, play a crucial role in the regeneration dynamics of Mediterranean oak forests.
doi: 10.1139/X08-089doi: 10.1139/X08-089The following values have no corresponding Zotero field: publisher: NRC Research Press
Keywords: Mediterranean oak species; Modelling; seed germination; seedling emergence; seedling survival (voyant); Soil water content

Soil water content and emergence time control seedling establishment in three co-occurring Mediterranean oak species - Urbieta, Itziar R; Pérez-Ramos, Ignacio M; Zavala, MIGUEL a; Marañón, Teodoro; Kobe, Richard K (Canadian Journal of Forest Research, 2008)
Tree species can differ in their responses to resource availability during the critical phase of establishment, which could influence forest dynamics. In Mediterranean forests, most of the attention has focused on the effects of shade and summer drought on seedling survival, but little is known about the effect of autumn to spring rains on earlier stages of recruitment. A sowing experiment was set up along natural light and water gradients with three co-occurring oak species (Quercus suber L. (cork oak), Quercus canariensis Willd. (Algerian oak), and Quercus pyrenaica Willd. (Pyrenean oak)) that show limited natural regeneration in southern Spain. Recruitment stages were monitored for 1 year. Models of seed germination, seedling emergence, and seedling survival as well as of overall recruitment patterns were developed as functions of light, soil moisture, and soil compaction. The influence of intraspecific variation in seed mass and emergence time were also tested. Excess soil water levels during the winter reduced germination and emergence and lengthened time to emergence (in waterlogged open areas), which in turn decreased seedling survival during the dry season. Seedlings from larger seeds were more likely to germinate and emerge. The results suggest that temporal and spatial variability of soil water content, mediated by emergence time and seed size, play a crucial role in the regeneration dynamics of Mediterranean oak forests.
doi: 10.1139/X08-089
Keywords: Mediterranean oak species; Modelling; seed germination; seedling emergence; seedling survival (voyant); Soil water content

Soil water content at the catchment level and plant water status relationships in a Mediterranean Quercus ilex forest - Bellot, J; Ortiz de Urbina, J M (Journal of Hydrology, 2008)
This paper presents an analysis of the forest hydrology and plant water status interaction, focusing on the relationship between the hydrological water balance at the catchment level and the predawn leaf water potential of the species Quercus ilex (holm oak). The catchment water balance approach was applied to a Mediterranean watershed forested with holm oak to evaluate the daily soil water reserve at the catchment level. After this, evapotranspiration and soil water content were combined to estimate the potential soil water reserve and evaluate plant water status at the catchment level. A close relationship was detected between leaf water potential and the soil water reserve, and was ﬁtted to a negative exponential curve to estimate predawn leaf water potential from a hydrological database. The proposed equation can help to predict the frequency, intensity, and length of droughts potentially capable of causing structural damage to the forest, from the hydrological time series records.
Keywords: Catchments; Plant water status; Predawn water potential; Quercus ilex; soil water; water balance

Soil water content at the catchment level and plant water status relationships in a Mediterranean Quercus ilex forest - Bellot, J.; Ortiz de Urbina, J. M. (Journal of Hydrology, 2008)
This paper presents an analysis of the forest hydrology and plant water status interaction, focusing on the relationship between the hydrological water balance at the catchment level and the predawn leaf water potential of the species Quercus ilex (holm oak). The catchment water balance approach was applied to a Mediterranean watershed forested with holm oak to evaluate the daily soil water reserve at the catchment level. After this, evapotranspiration and soil water content were combined to estimate the potential soil water reserve and evaluate plant water status at the catchment level. A close relationship was detected between leaf water potential and the soil water reserve, and was ﬁtted to a negative exponential curve to estimate predawn leaf water potential from a hydrological database. The proposed equation can help to predict the frequency, intensity, and length of droughts potentially capable of causing structural damage to the forest, from the hydrological time series records.
Keywords: Catchments; Plant water status; Predawn water potential; Quercus ilex; soil water; water balance

Spanish Wood Pasture: Origin and Durability of an Historical Wooded Landscape in Mediterranean Europe - Clément, Vincent (Environment and History, 2008)
Spanish dehesas, the most extensive wood pastures in Mediterranean Europe, are a vivid example for demonstrating that the impact of rural communities on forests has not always been a bad thing. Environmental history is vital for understanding this cultural landscape. This article first analyses the origin of the dehesa. The border logic and the medieval Reconquest are elements that undoubtedly played a decisive part in its genesis; but, for the significance of Roman influence in Spain, it is necessary to consider the question of the possible existence of dehesas in Antiquity. The second aspect concerns the spreading of this landscape from the Middle Ages onwards. Dehesas are usually linked to the large properties owned by military orders, but most of all the spreading of the dehesa was favoured by the rise of transhumance from the thirteenth century onwards. Finally, the article emphasises that the durability of the Spanish wood pasture can be explained by a combination of several factors: insecurity along the border, the fact that transhumance was the most important industry in Spain for many centuries, and the protective laws adopted by the rural communities in order to protect their dehesas.
Keywords: Dehesa; Mesta; Spanish Reconquest; Transhumance; woodland landscape

Spanish Wood Pasture: Origin and Durability of an Historical Wooded Landscape in Mediterranean Europe - Clément, Vincent (Environment and History, 2008)
Spanish dehesas, the most extensive wood pastures in Mediterranean Europe, are a vivid example for demonstrating that the impact of rural communities on forests has not always been a bad thing. Environmental history is vital for understanding this cultural landscape. This article first analyses the origin of the dehesa. The border logic and the medieval Reconquest are elements that undoubtedly played a decisive part in its genesis; but, for the significance of Roman influence in Spain, it is necessary to consider the question of the possible existence of dehesas in Antiquity. The second aspect concerns the spreading of this landscape from the Middle Ages onwards. Dehesas are usually linked to the large properties owned by military orders, but most of all the spreading of the dehesa was favoured by the rise of transhumance from the thirteenth century onwards. Finally, the article emphasises that the durability of the Spanish wood pasture can be explained by a combination of several factors: insecurity along the border, the fact that transhumance was the most important industry in Spain for many centuries, and the protective laws adopted by the rural communities in order to protect their dehesas.
Keywords: Dehesa; Mesta; Spanish Reconquest; Transhumance; woodland landscape

A spatial distribution model of cork oak (Quercus suber) in southwestern Spain: A suitable tool for reforestation - Hidalgo, P J; Marín, J M; Quijada, J; Moreira, J M (Forest Ecology and Management, 2008)
Cork oak (Quercus suber) is an evergreen tree characterized by a thick bark, which grows in Mediterranean schlerophyllous forests. It is most prevalent in the southwestern Iberian Peninsula. Despite the potential of the province of Huelva (southwestern Spain) to maintain mature forests of cork oak, the tree has been severely depleted and most forests have either disappeared or are seriously threatened. This paper presents a spatial distribution model of cork oak for the province of Huelva with a view to determining the optimal areas for reforestation. The model draws on all available digital cartographic information with respect to cork oak distribution: topographic data (altitude, slope and orientation) were obtained from a Digital Terrain Model (20 m scale); rainfall, temperature and PET models were based on data collected from a network of meteorological stations; litologic data derive from the litologic map of Huelva (1:100,000). The result of this work is a mesh of points at a resolution of 100 m, sufﬁcient to meet the needs of any kind of reforestation or management programmes in the area studied. Each point of this mesh contains the corresponding values for bioclimatic, topographic and litologic variables in a georeferenced data matrix. The independent variables responsible for cork oak distribution (binary dependent variables) were then identiﬁed by means of binary logistic regression analysis. North-facing slopes, abundant annual rainfall and litology were the main explaining variables. The spatial distribution model was produced by applying the formula obtained to spatial analysis software. This model is proposed as a basis for future reforestation plans, especially in those areas most affected by forest ﬁres.
Keywords: binary logistic regression; climatic modeling; Cork oak; Quercus suber; Reforestation; spatial analysis

Stomatal uptake and stomatal deposition of ozone in isoprene and monoterpene emitting plants - Fares, S; Loreto, F; Kleist, E; Wildt, J (Plant Biology, 2008)
Volatile isoprenoids were reported to protect plants against ozone. To understand whether this could be the result of a direct scavenging of ozone by these molecules, the stomatal and non-stomatal uptake of ozone was estimated in plants emitting isoprene or monoterpenes. Ozone uptake by holm oak (Quercus ilex, a monoterpene emitter) and black poplar (Populus nigra, an isoprene emitter) was studied in whole plant enclosures (continuously stirred tank reactors, CSTR). The ozone uptake by plants was estimated measuring ozone concentration at the inlet and outlet of the reactors, after correcting for the uptake of the enclosure materials. Destruction of ozone at the cuticle or at the plant stems was found to be negligible compared to the ozone uptake through the stomata. For both plant species, a relationship between stomatal conductance and ozone uptake was found. For the poplar, the measured ozone losses were explained by the uptake of ozone through the stomata only, and ozone destruction by gas phase reactions with isoprene was negligible. For the oak, gas phase reactions of ozone with the monoterpenes emitted by the plants contributed significantly to ozone destruction. This was confirmed by two different experiments showing a) that in cases of high stomatal conductance but under low CO2 concentration, a reduction of monoterpene emission was still associated with reduced O3 uptake; and b) that ozone losses due to the gas phase reactions only can be measured when using the exhaust from a plant chamber to determine the gas phase reactivity in an empty reaction chamber. Monoterpenes can therefore relevantly scavenge ozone at leaf level contributing to protection against ozone.
Keywords: isoprene; Monoterpenes; Ozone uptake; photosynthesis; reaction chambers; Stomatal conductance

Stomatal uptake and stomatal deposition of ozone in isoprene and monoterpene emitting plants - Fares, S.; Loreto, F.; Kleist, E.; Wildt, J. (Plant Biology, 2008)
Volatile isoprenoids were reported to protect plants against ozone. To understand whether this could be the result of a direct scavenging of ozone by these molecules, the stomatal and non-stomatal uptake of ozone was estimated in plants emitting isoprene or monoterpenes. Ozone uptake by holm oak (Quercus ilex, a monoterpene emitter) and black poplar (Populus nigra, an isoprene emitter) was studied in whole plant enclosures (continuously stirred tank reactors, CSTR). The ozone uptake by plants was estimated measuring ozone concentration at the inlet and outlet of the reactors, after correcting for the uptake of the enclosure materials. Destruction of ozone at the cuticle or at the plant stems was found to be negligible compared to the ozone uptake through the stomata. For both plant species, a relationship between stomatal conductance and ozone uptake was found. For the poplar, the measured ozone losses were explained by the uptake of ozone through the stomata only, and ozone destruction by gas phase reactions with isoprene was negligible. For the oak, gas phase reactions of ozone with the monoterpenes emitted by the plants contributed significantly to ozone destruction. This was confirmed by two different experiments showing a) that in cases of high stomatal conductance but under low CO2 concentration, a reduction of monoterpene emission was still associated with reduced O3 uptake; and b) that ozone losses due to the gas phase reactions only can be measured when using the exhaust from a plant chamber to determine the gas phase reactivity in an empty reaction chamber. Monoterpenes can therefore relevantly scavenge ozone at leaf level contributing to protection against ozone.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: isoprene; Monoterpenes; Ozone uptake; photosynthesis; reaction chambers; Stomatal conductance

Stress assessment of argan (Argania spinosa (L.) Skeels) in response to land uses across an aridity gradient: Translational asymmetry and branch fractal dimension - ALADOS, C L; El Aich, A (Journal of Arid Environments, 2008)
We used Translational Asymmetry (TA) of the annual stem, branch growth pattern and fractal dimension to quantify stress during development of argan (Argania spinosa (L.) Skeels) throughout its range in Morocco. Under communal grazing conditions known as ‘‘mouchaˆa’’ (Grazing Management), the branch fractal dimension was reduced and the TA of plants increased, reﬂecting the stressful conditions in which the argan trees were growing. Under Wild growing conditions, developmental instability increased as moisture decreased across a gradient of aridity. Under Barley Management conditions (barley crops are cultivated underneath of argan), argan increased branch complexity (branch fractal dimension) in the mildest area (Essaouira), which imposed an additional cost that results in increased TA. The results of the study best ﬁt the predictions that the level of asymmetry and fractal dimension reﬂects stressful conditions, which can be used to monitor the effect of environmental stress in the conservation of argan ecosystem.
Keywords: argan; aridity; developmental instability; environmental stress; fractal; Grazing; land use; translational asymmetry

Stress assessment of argan (Argania spinosa (L.) Skeels) in response to land uses across an aridity gradient: Translational asymmetry and branch fractal dimension - Alados, C. L.; El Aich, A. (Journal of Arid Environments, 2008)
We used Translational Asymmetry (TA) of the annual stem, branch growth pattern and fractal dimension to quantify stress during development of argan (Argania spinosa (L.) Skeels) throughout its range in Morocco. Under communal grazing conditions known as ‘‘mouchaˆa’’ (Grazing Management), the branch fractal dimension was reduced and the TA of plants increased, reﬂecting the stressful conditions in which the argan trees were growing. Under Wild growing conditions, developmental instability increased as moisture decreased across a gradient of aridity. Under Barley Management conditions (barley crops are cultivated underneath of argan), argan increased branch complexity (branch fractal dimension) in the mildest area (Essaouira), which imposed an additional cost that results in increased TA. The results of the study best ﬁt the predictions that the level of asymmetry and fractal dimension reﬂects stressful conditions, which can be used to monitor the effect of environmental stress in the conservation of argan ecosystem.
Keywords: argan; aridity; developmental instability; environmental stress; fractal; Grazing; land use; translational asymmetry

Structural analysis of woody species in Mediterranean old fields - La Mantia, T; Rühl, J; Pasta, S; Campisi, D G; Terrazzino, G (Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology, 2008)
Abstract The study analyses the changes in vegetation structure and composition within a sere of secondary succession at Pantelleria Island (Sicilian Channel, Italy). It aims to show that not only phytosociological data but also structural parameters, like woody species? height and spatial distribution indices are useful to describe and interpret renaturation processes. Woody species structure was recorded on abandoned terraces, both on north-facing and on south-facing slopes. Relevés were made in fallows representing five different stages of succession. The pace of succession, measured through the analysis of woody species cover, basal area, height distribution and spatial indices, resulted quite rapid: already after 50 years of abandonment terraces are covered by dense maquis communities. Our study also revealed that different plant species or groups prevail during colonisation dynamics, mostly depending on exposition, a factor which strongly influences also the speed of colonisation by woody species. In this case study, human activity seems to be unnecessary to accelerate the process of renaturation, except in some unfavourable contexts. Species turnover rate, biodiversity value, and structural evolution along progressive succession must be taken into account in nature management and conservation policies of terraced landscapes, which are nowadays one of the most endangered landscape types throughout the Mediterranean area.
doi: 10.1080/11263500802410793
Keywords: Abandonment; landscape conservation; Secondary succession; Sicily; Spatial pattern

TDR measurement of stem and soil water content in two Mediterranean oak species - HERNÁNDEZ-SANTANA, VIRGINIA; MARTÍNEZ-FERNÁNDEZ, JOSÉ (Hydrological Sciences Journal, 2008)
Abstract Since 1990s, time domain reflectometry (TDR) has been applied to estimate the stem water content of living trees. Here, new calibration equations relating the apparent dielectric constant (Ka ) to the volumetric water content (?) were developed for two Mediterranean oak species. Our calibration equations differ from those previously calculated for other species, suggesting that stem water contents could be monitored more accurately using species-specific curves. The stem water content in the trees of these species and the surrounding soil were monitored with TDR to examine the feasibility of this technology for recording changes in trunk water storage. The average stem water contents of the oaks reflect the soil water contents, and the temporal differences observed (17%) point to the importance of trunk water for coping with soil water deficit. Although it would be very useful to obtain a single function to estimate the stem water content of trees, it remains necessary to obtain the results in more species.
doi: 10.1623/hysj.53.4.921
Keywords: Quercus pyrenaica; Quercus rotundifolia; Soil moisture; stem water content; TDR

TDR measurement of stem and soil water content in two Mediterranean oak species - HERNÁNDEZ-SANTANA, VIRGINIA; MARTÍNEZ-FERNÁNDEZ, JOSÉ (Hydrological Sciences Journal, 2008)
Abstract Since 1990s, time domain reflectometry (TDR) has been applied to estimate the stem water content of living trees. Here, new calibration equations relating the apparent dielectric constant (Ka ) to the volumetric water content (?) were developed for two Mediterranean oak species. Our calibration equations differ from those previously calculated for other species, suggesting that stem water contents could be monitored more accurately using species-specific curves. The stem water content in the trees of these species and the surrounding soil were monitored with TDR to examine the feasibility of this technology for recording changes in trunk water storage. The average stem water contents of the oaks reflect the soil water contents, and the temporal differences observed (17%) point to the importance of trunk water for coping with soil water deficit. Although it would be very useful to obtain a single function to estimate the stem water content of trees, it remains necessary to obtain the results in more species.
doi: 10.1623/hysj.53.4.921doi: 10.1623/hysj.53.4.921The following values have no corresponding Zotero field: publisher: Taylor & Francis
Keywords: Quercus pyrenaica; Quercus rotundifolia; Soil moisture; stem water content; TDR

Trace element accumulation in woody plants of the Guadiamar Valley, SW Spain: a large-scale phytomanagement case study. - Domínguez, María T; Marañón, Teodoro; Murillo, José M; Schulin, Rainer; Robinson, Brett H (Environmental pollution (Barking, Essex : 1987), 2008)
Phytomanagement employs vegetation and soil amendments to reduce the environmental risk posed by contaminated sites. We investigated the distribution of trace elements in soils and woody plants from a large phytomanaged site, the Guadiamar Valley (SW Spain), 7 years after a mine spill, which contaminated the area in 1998. At spill-affected sites, topsoils (0-25 cm) had elevated concentrations of As (129 mg kg(-1)), Bi (1.64 mg kg(-1)), Cd (1.44 mg kg(-1)), Cu (115 mg kg(-1)), Pb (210 mg kg(-1)), Sb (13.8 mg kg(-1)), Tl (1.17 mg kg(-1)) and Zn (457 mg kg(-1)). Trace element concentrations in the studied species were, on average, within the normal ranges for higher plants. An exception was white poplar (Populus alba), which accumulated Cd and Zn in leaves up to 3 and 410 mg kg(-1) respectively. We discuss the results with regard to the phytomanagement of trace element contaminated sites.
Keywords: Bioaccumulation; biodegradation; Environmental; Environmental Monitoring; Environmental Monitoring: methods; Heavy; Heavy metal; Heavy: analysis; Mass spectrometry; metals; Mining; Olea; Olea europaea; Olea: chemistry; Phytoremediation; Plant Leaves; Plant Leaves: chemistry; Populus; Populus alba; Populus: chemistry; Quercus; Quercus ilex; Quercus: chemistry; Soil; Soil Pollutants; Soil Pollutants: analysis; Soil: analysis; Spain; Species Specificity

Trace element accumulation in woody plants of the Guadiamar Valley, SW Spain: a large-scale phytomanagement case study. - Domínguez, María T.; Marañón, Teodoro; Murillo, José M.; Schulin, Rainer; Robinson, Brett H. (Environmental pollution (Barking, Essex : 1987), 2008)
Phytomanagement employs vegetation and soil amendments to reduce the environmental risk posed by contaminated sites. We investigated the distribution of trace elements in soils and woody plants from a large phytomanaged site, the Guadiamar Valley (SW Spain), 7 years after a mine spill, which contaminated the area in 1998. At spill-affected sites, topsoils (0-25 cm) had elevated concentrations of As (129 mg kg(-1)), Bi (1.64 mg kg(-1)), Cd (1.44 mg kg(-1)), Cu (115 mg kg(-1)), Pb (210 mg kg(-1)), Sb (13.8 mg kg(-1)), Tl (1.17 mg kg(-1)) and Zn (457 mg kg(-1)). Trace element concentrations in the studied species were, on average, within the normal ranges for higher plants. An exception was white poplar (Populus alba), which accumulated Cd and Zn in leaves up to 3 and 410 mg kg(-1) respectively. We discuss the results with regard to the phytomanagement of trace element contaminated sites.
The following values have no corresponding Zotero field: accession-num: 17602809
Keywords: Bioaccumulation; biodegradation; Environmental; Environmental Monitoring; Environmental Monitoring: methods; Heavy; Heavy metal; Heavy: analysis; Mass spectrometry; metals; Mining; Olea; Olea europaea; Olea: chemistry; Phytoremediation; Plant Leaves; Plant Leaves: chemistry; Populus; Populus alba; Populus: chemistry; Quercus; Quercus ilex; Quercus: chemistry; Soil; Soil Pollutants; Soil Pollutants: analysis; Soil: analysis; Spain; Species Specificity

Traditional Land-Use Systems: Sustainability, Efficiency and Biodiversity - Hindmarch, Colin; Pienkowski, Mike (Land Management: The Hidden Costs, 2008)
Currently used methods of intensive land man- agement are unsustainable (Section 2), and our attempts to protect the environment fiom their damaging effects have at best been limited, and in some cases counter-productive (Section 3). Robust, biologically-rich landscapes seem to be the natural result of using locally adapted land-management systems. Although these are not as productive as intensive systems, they have a rich variety of produce, and are sustainable, efficient and capable of providing the basis for biological conservation at a number of ecologi- cal des. Unfortunately, they are now largely confined to the least versatile soils, and are dding.
Keywords: palaeo-ecological view; pastoral systems; sustainable land-uses; traditional land-uses systems

Transformaciones de un ecosistema palustre.: La gran ciénaga del Bermejo-Mendoza, siglos XVIII y XIX - Prieto, M R; Abraham, E; Dussel, P (Multequina, 2008)
The area that presently comprises part of the departments of Guaymallen, Lavalle and Maipu in the province f Mendoza was occupied until the beginning of the 20 th century by a large marshy and lacustrine system. This system has undergone variations in its extension and water volume along several centuries until its desiccation in the first quarter of the 20 th century. By the turn of the 18 th century and beginning of the 19 th the marsh started a disproportionate growth reaching enormous dimensions, thus provoking the loss of farming land and pasture fields. Our interest has been the study of the natural and anthropic causes that occasioned the transformation of this ecosystem. For this, we have resorted to historical documents, ancient maps, descriptions by voyageurs and scientists, complemented by field work in the relicts of the old marsh zone plus the analysis of aerial photographs and satellite images. The phenomenon can be attributed to the wrong watering management in the higher oasis zones, to the topographic characteristic of the terrain and the deficient drainage, jointly with geotectonic phenomena and a period of large snow precipitation in the cordillera that caused the ascent of the phreatic layers.
Keywords: climatic variations; dehesa environment; Environmental history; hydric resources

Transformaciones de un ecosistema palustre.: La gran ciénaga del Bermejo-Mendoza, siglos XVIII y XIX - Prieto, M. R.; Abraham, E.; Dussel, P. (Multequina, 2008)
The area that presently comprises part of the departments of Guaymallen, Lavalle and Maipu in the province f Mendoza was occupied until the beginning of the 20 th century by a large marshy and lacustrine system. This system has undergone variations in its extension and water volume along several centuries until its desiccation in the first quarter of the 20 th century. By the turn of the 18 th century and beginning of the 19 th the marsh started a disproportionate growth reaching enormous dimensions, thus provoking the loss of farming land and pasture fields. Our interest has been the study of the natural and anthropic causes that occasioned the transformation of this ecosystem. For this, we have resorted to historical documents, ancient maps, descriptions by voyageurs and scientists, complemented by field work in the relicts of the old marsh zone plus the analysis of aerial photographs and satellite images. The phenomenon can be attributed to the wrong watering management in the higher oasis zones, to the topographic characteristic of the terrain and the deficient drainage, jointly with geotectonic phenomena and a period of large snow precipitation in the cordillera that caused the ascent of the phreatic layers.
Keywords: climatic variations; dehesa environment; Environmental history; hydric resources

Trends in the surface vegetation dynamics of the national parks of Spain as observed by satellite sensors - Alcaraz-Segura, Domingo; Cabello, Javier; Paruelo, José M.; Delibes, Miguel (Applied Vegetation Science, 2008)
Questions: What are the current dynamics, as observed by synoptic sensors, of surface vegetation in Spanish protected areas? Are these areas and their vegetation types uniformly affected by the increase in vegetation greenness detected throughout Europe? Location: Iberian National Parks of Spain. Methods: We used the normalized difference vegetation index (NDVI) from global inventory modeling and mapping studies (GIMMS) advanced very high resolution radiometer (AVHRR) dataset to monitor surface vegetation. NDVI is a surrogate for the photosynthetically active radiation absorbed by vegetation (fAPAR). This functional attribute has a short-time response to disturbances, is connected to ecosystem services and can be monitored through remote sensing. First, we provide a baseline description of the NDVI dynamics in the parks and analysed its temporal trends (1981-2003). Then, we evaluated the relationships of the seasonal dynamics and interannual trends with the climate conditions, vegetation types and conservation histories of the parks. Results: The parks showed two patterns of NDVI dynamics corresponding to Mediterranean and Eurosiberian regions. Most parks showed areas with positive NDVI trends that tended to have higher proportions of Mediterranean coniferous and mixed forests, oro-Mediterranean scrublands, heathlands, maquis and garrigues. Negative trends were scarce and associated with marshes and Alpine coniferous forests. The lack of a common response in all parks was related to their different environmental conditions, management, and conservation histories. Conclusions: National parks are changing in the short term but not uniformly. This study represents a basis for the incorporation of functional attributes of ecosystems in the management and monitoring of protected areas in the face of global change.
Keywords: Global environmental change; monitoring; National Park conservation; NDVI; Remote sensing.

Trends in the surface vegetation dynamics of the national parks of Spain as observed by satellite sensors - Alcaraz-Segura, Domingo; Cabello, Javier; Paruelo, José M; Delibes, Miguel (Applied Vegetation Science, 2008)
Questions: What are the current dynamics, as observed by synoptic sensors, of surface vegetation in Spanish protected areas? Are these areas and their vegetation types uniformly affected by the increase in vegetation greenness detected throughout Europe? Location: Iberian National Parks of Spain. Methods: We used the normalized difference vegetation index (NDVI) from global inventory modeling and mapping studies (GIMMS) advanced very high resolution radiometer (AVHRR) dataset to monitor surface vegetation. NDVI is a surrogate for the photosynthetically active radiation absorbed by vegetation (fAPAR). This functional attribute has a short-time response to disturbances, is connected to ecosystem services and can be monitored through remote sensing. First, we provide a baseline description of the NDVI dynamics in the parks and analysed its temporal trends (1981-2003). Then, we evaluated the relationships of the seasonal dynamics and interannual trends with the climate conditions, vegetation types and conservation histories of the parks. Results: The parks showed two patterns of NDVI dynamics corresponding to Mediterranean and Eurosiberian regions. Most parks showed areas with positive NDVI trends that tended to have higher proportions of Mediterranean coniferous and mixed forests, oro-Mediterranean scrublands, heathlands, maquis and garrigues. Negative trends were scarce and associated with marshes and Alpine coniferous forests. The lack of a common response in all parks was related to their different environmental conditions, management, and conservation histories. Conclusions: National parks are changing in the short term but not uniformly. This study represents a basis for the incorporation of functional attributes of ecosystems in the management and monitoring of protected areas in the face of global change.
Keywords: Global environmental change; monitoring; National Park conservation; NDVI; Remote sensing.

Using the maximum Mutual Information criterion to textural Feature Selection for satellite image classification - Kerroum, M A; Hammouch, A; Aboutajdine, D; Bellaachia, A (Computers and Communications, 2008. ISCC 2008. IEEE Symposium on, 2008)
This paper presents and evaluates the use of the maximum mutual information criterion to textural feature selection for satellite image classification. Our approach is based on a recent work of Mutual Information Feature Selector Algorithm. The effectiveness of the proposed approach is evaluated on real data. In fact, the textural features are extracted using the cooccurrence matrix from two forest zones of SPOT HRV(XS) image in the region of Rabat, Morocco. The experimental tests of this study prove that the proposed approach gives a better performance for satellite image classification than classical methods such as principal components analysis (PCA) and linear discriminant analysis (LDA). The classifier used in this work is the support vectors machine (SVM).
Keywords: Cooccurrence Matrix; LDA; mutual information; PCA; Satellite Image Classi- fication; SVM; Textural Feature Selection

Water resources and environmental change in a Mediterranean environment: The south-west sector of the Duero river basin (Spain) - Ceballos-Barbancho, Antonio; Morán-Tejeda, Enrique; Luengo-Ugidos, Miguel Ángel; Llorente-Pinto, José Manuel (Journal of Hydrology, 2008)
In the present work we analyse the temporal trend of water supplies to a network of basins, representative of the Mediterranean climate and plant cover, and its relationship with the evolution of temperatures, precipitation, and the changes that have occurred in the plant cover with time. The results point to an important decrease in water supply, with a high degree of dependence on precipitation (r = 0.85; p-value < 0.001). Important changes are also seen in the monthly distribution of water discharges due to modiﬁcations that have occurred in the intra-annual distribution of precipitation and an increase in temperatures in spring and summer. The rivers studied are losing their snow regime, with very important reductions in the winter and spring discharges. The results show that to date the changes detected in the forest have not affected the water discharges of the rivers. This absence of effect is probably because the changes observed in the plant cover are currently below the threshold after which it is possible to detect the effect of the forest on water discharges and because the interannual variability in rainfall and discharge in Mediterranean environments is so high that it masks other time-dependent changes. The planning and management of water resources should take these changes into consideration with respect to the functioning of hydroclimatic systems
Keywords: Duero river; Environmental change; Headwaters; Mediterranean; Precipitation; Water discharge

Wild boars (Sus scrofa) affect the recruitment rate and spatial distribution of holm oak (Quercus ilex) - Gómez, Jose M.; Hódar, José a. (Forest Ecology and Management, 2008)
The role of herbivores in controlling plant population abundance and distribution is unclear. We experimentally determine the effect of damage by wild boars (Sus scrofa) in recruitment rate and spatial pattern of a Mediterranean tree, the holm oak (Quercus ilex). We monitored oak establishment in the Sierra Nevada of southeastern Spain during 4 years (1999–2002) in four plots, two fenced and two unfenced that were used as controls. In addition, we planted 1-year-old seedlings in all microhabitats, both in fenced and control plots, to experimentally determine the effect of wild boar on their microhabitat-dependent survival. Despite seedling abundance being similar inside and outside the fences, sapling abundance diminished up to 50% in unfenced plots compared to fenced plots. Wild boars also seemed to modify the spatial distribution of seedlings and saplings. Whereas seedlings were most abundant under pines both in fenced and control plots, sapling abundance was highest under pine trees in fenced plots, but similarly abundant under pines or shrubs in control plots. This change in spatial pattern was due to the effect of wild boars killing seedlings when looking for food under pines. The effects of the different mortality factors were not additive. Where ungulates are absent, recruitment is high and occurs under oaks and especially under pines. Where wild boars are present, recruitment diminishes and occurs mostly under shrubs and pines. Wild boars arrest population growth and modify the spatial pattern of recruitment.
Keywords: Facilitation; herbivory; Population regeneration; Quercus ilex; Seedling establishment limitation; Seedling recruitment; Wild boars

Within-tree and between-tree variation of wood density components in cork oak trees in two sites in Portugal - Knapic, Sofia; Louzada, José L; Leal, Sofia; Pereira, Helena (Forestry, 2008)
The axial and radial variation of wood density was studied using microdensitometry in cork oaks (Quercus suber) in two sites in Portugal. The observations were made in mature trees under cork production and in juvenile trees before the first cork extraction, at three height levels (stem base, 1.3 m and before stem bifurcation). The cork oak wood revealed a very high mean density (0.884–1.068 g cm−3). Differences between earlywood and latewood were small (0.866 and 1.061 g cm−3, respectively). Latewood corresponded on average to 61 per cent of the total. The variation of density between trees was statistically highly significant, but no differences were found between the two sites. The within-tree axial variation was negligible but the radial direction within a cross-section was one of the main origins of variation of the density components (18 per cent of the total variation). The density decreased from pith to cambium and this radial variation corresponded to 19–24 per cent of the total variation of wood density. Overall, the magnitude of density variations between and within cork oaks was small and an advantageous factor for their use for quality wood products.
10.1093/forestry/cpn012
Keywords: axial variation (voyant); cork oak trees; radial variation; Wood density

Would you choose your preferred option? Comparing choice and recoded ranking experiments - Caparros, Alejandro; Oviedo, Jose L; Campos, Pablo (AMERICAN JOURNAL OF AGRICULTURAL ECONOMICS, 2008)
Previous research has shown that results from a choice experiment are statistically different from those obtained from a ranking experiment that is recoded and treated as a choice experiment using only the first rank. By avoiding some of the shortcomings of previous comparisons, we obtain the opposite results using data from the valuation of a cork oak reforestation program in the south of Spain. Structural models and welfare estimations are statistically indistinguishable irrespective of the use of parametric or bootstrapping tests. Further, we employ follow-up questions and subsample analysis to test whether divergences appear when potential effects are isolated.
Keywords: choice modeling; conjoint analysis; cork oak reforestation; environmental preferences; recoded ranking

The 8.2ka event and Early–Mid Holocene forests, fires and flooding in the Central Ebro Desert, NE Spain - Davis, B.; Stevenson, A. (Quaternary Science Reviews, 2007)
The impact of the 8.2 ka cooling event during the Early–Mid Holocene has not been widely observed in Southern Europe, which in contrast to Northern Europe, was already experiencing a cooler than present climate at this time. Multi-proxy analysis of sediment cores from two closed-basin saline lakes in the Central Ebro Desert (NE Spain) has allowed us to investigate the impact of climatic changes around the time of this event in more detail. Long-term changes in climate between the Early and Mid Holocene indicate a shift in winter to a more positive NAO, resulting in declining lake levels in one lake sensitive to winter groundwater recharge, and cooler winter temperatures reconstructed from pollen–climate analysis. Reconstructed summer temperatures also declined over this period while annual precipitation and forest cover increased, interpreted as a result of enhanced convection-driven summer precipitation association with a northward displacement of the sub-tropical high pressure. Around 8.2 ka, a marked increase in ﬁre frequency is shown between ca 8.8 and 8.0 ka BP, along with an expansion of ﬁre-tolerant evergreen oak and peak in water levels in a second storm run-off fed lake. A maximum in ﬁre intensity occurred with the deposition of a charcoal layer at both lake sites dated to 81507130 and 82857135 cal BP, respectively. The increase in ﬁre is largely attributed to a temporary return southward of the summer sub-tropical high pressure over the Mediterranean, which not only increased summer aridity, but also caused a contradictory regional warming before Hemispheric cooling set in
Keywords: climate changes; Ebro basin; Fire frequency (voyant); Holocene; Mediterranean; water levels; winter/summer temperatures

The 8.2ka event and Early–Mid Holocene forests, fires and flooding in the Central Ebro Desert, NE Spain - Davis, B; Stevenson, A (Quaternary Science Reviews, 2007)
The impact of the 8.2 ka cooling event during the Early–Mid Holocene has not been widely observed in Southern Europe, which in contrast to Northern Europe, was already experiencing a cooler than present climate at this time. Multi-proxy analysis of sediment cores from two closed-basin saline lakes in the Central Ebro Desert (NE Spain) has allowed us to investigate the impact of climatic changes around the time of this event in more detail. Long-term changes in climate between the Early and Mid Holocene indicate a shift in winter to a more positive NAO, resulting in declining lake levels in one lake sensitive to winter groundwater recharge, and cooler winter temperatures reconstructed from pollen–climate analysis. Reconstructed summer temperatures also declined over this period while annual precipitation and forest cover increased, interpreted as a result of enhanced convection-driven summer precipitation association with a northward displacement of the sub-tropical high pressure. Around 8.2 ka, a marked increase in ﬁre frequency is shown between ca 8.8 and 8.0 ka BP, along with an expansion of ﬁre-tolerant evergreen oak and peak in water levels in a second storm run-off fed lake. A maximum in ﬁre intensity occurred with the deposition of a charcoal layer at both lake sites dated to 81507130 and 82857135 cal BP, respectively. The increase in ﬁre is largely attributed to a temporary return southward of the summer sub-tropical high pressure over the Mediterranean, which not only increased summer aridity, but also caused a contradictory regional warming before Hemispheric cooling set in
Keywords: climate changes; Ebro basin; Fire frequency (voyant); Holocene; Mediterranean; water levels; winter/summer temperatures

The agricultural consequences of colonial contacts on the Iberian Peninsula in the first millennium b.c - Buxó, Ramon (Vegetation History and Archaeobotany, 2007)
The Iron Age archaeobotanical record on the Iberian Peninsula shows how the Phoenician and Greek colonisers caused the indigenous Iberians to change the management of the agricultural resources and the crops which they grew. These colonisers also brought about the development of viticulture and olive cultivation. The importance of agricultural products in the trade network which was stimulated by the colonisers may have encouraged new farming systems, as well as surplus capacity in the native agriculture in the region.
Keywords: á agricultural products á; Agricultural products; Archaeobotanical record; archaeobotanical record á; c; cal b; Early Iron Age; from the ninth century; Iron Age; Phoenician and Greek colonisation; to the romanisation of; Trade network; trade network á early

The agricultural consequences of colonial contacts on the Iberian Peninsula in the first millennium b.c - Buxó, Ramon (Vegetation History and Archaeobotany, 2007)
The Iron Age archaeobotanical record on the Iberian Peninsula shows how the Phoenician and Greek colonisers caused the indigenous Iberians to change the management of the agricultural resources and the crops which they grew. These colonisers also brought about the development of viticulture and olive cultivation. The importance of agricultural products in the trade network which was stimulated by the colonisers may have encouraged new farming systems, as well as surplus capacity in the native agriculture in the region.
Keywords: á agricultural products á; Agricultural products; Archaeobotanical record; archaeobotanical record á; c; cal b; Early Iron Age; from the ninth century; Iron Age; Phoenician and Greek colonisation; to the romanisation of; Trade network; trade network á early

Antibacterial activity of Quercus ilex bark's extracts. - Berahou, a; Auhmani, A; Fdil, N; Benharref, A; Jana, M; Gadhi, C a (Journal of ethnopharmacology, 2007)
The antibacterial activity of different extracts of Quercus ilex bark (Fagaceae) was studied in vitro against seven reference strains of bacteria by using a disc-diffusion method and agar-dilution method. The ethyl acetate extract (QE), n-butanol extract (QB) and final aqueous layer (QA) were effective against all bacterial strains tested at MICs ranging from 128 to 512 microg/ml. The n-hexane extract (QH) and dichloromethane extract (QD) showed no activity.
Keywords: Agar-dilution method; Antibacterial activity; Bark; Disc-diffusion method; Organic extracts; Quercus ilex L.

Antibacterial activity of Quercus ilex bark's extracts. - Berahou, a; Auhmani, A.; Fdil, N.; Benharref, A.; Jana, M.; Gadhi, C. a (Journal of ethnopharmacology, 2007)
The antibacterial activity of different extracts of Quercus ilex bark (Fagaceae) was studied in vitro against seven reference strains of bacteria by using a disc-diffusion method and agar-dilution method. The ethyl acetate extract (QE), n-butanol extract (QB) and final aqueous layer (QA) were effective against all bacterial strains tested at MICs ranging from 128 to 512 microg/ml. The n-hexane extract (QH) and dichloromethane extract (QD) showed no activity.
The following values have no corresponding Zotero field: accession-num: 17513077
Keywords: Agar-dilution method; Antibacterial activity; Bark; Disc-diffusion method; Organic extracts; Quercus ilex L.

An application case of ecological indicator values (Zeigerwerte) calculated with a simple algorithmic approach - Fanelli, G.; Pignatti, S.; Testi, A. (Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology, 2007)
Abstract The vegetation of the study site near Rome (Castelporziano Estate), where different woodland types occur, was analysed on the basis of ecological indicator values (Zeigerwerte) for light, temperature, continentality of climate, soil moisture, soil pH and nitrogen. Indicator values were estimated with Hill's reprediction algorithm for the flora of Central-Southern Italy relying on a database of 4,207 original relevés representing a balanced survey of the vegetation of this and surrounding areas. It was possible to obtain indicator values for an important fraction of the Italian Mediterranean flora. Results are ecologically reasonable, and it was possible to find strong correlation between the recalculated values and a few environmental variables. These correlations were not significant in an analogous test with subjectively derived scores of Ellenberg indicator values.
From Duplicate 1 (An application case of ecological indicator values (Zeigerwerte) calculated with a simple algorithmic approach - Fanelli, G; Pignatti, S; Testi, A)
Keywords: correlation; Italy; reprediction algorithm; vegetation ecology

An application case of ecological indicator values (Zeigerwerte) calculated with a simple algorithmic approach - Fanelli, G.; Pignatti, S.; Testi, a (Plant Biosystems - An International Journal Dealing with all Aspects of Plant Biology, 2007)
Abstract The vegetation of the study site near Rome (Castelporziano Estate), where different woodland types occur, was analysed on the basis of ecological indicator values (Zeigerwerte) for light, temperature, continentality of climate, soil moisture, soil pH and nitrogen. Indicator values were estimated with Hill's reprediction algorithm for the flora of Central-Southern Italy relying on a database of 4,207 original relevés representing a balanced survey of the vegetation of this and surrounding areas. It was possible to obtain indicator values for an important fraction of the Italian Mediterranean flora. Results are ecologically reasonable, and it was possible to find strong correlation between the recalculated values and a few environmental variables. These correlations were not significant in an analogous test with subjectively derived scores of Ellenberg indicator values.
From Duplicate 1 (An application case of ecological indicator values (Zeigerwerte) calculated with a simple algorithmic approach - Fanelli, G; Pignatti, S; Testi, A)From Duplicate 1 (An application case of ecological indicator values (Zeigerwerte) calculated with a simple algorithmic approach - Fanelli, G; Pignatti, S; Testi, A)The following values have no corresponding Zotero field: publisher: Taylor & Francis
Keywords: correlation; Italy; reprediction algorithm; vegetation ecology

Application of BIOME-BGC to simulate Mediterranean forest processes - Chiesi, M.; Maselli, F.; Moriondo, M.; Fibbi, L.; Bindi, M.; Running, S. W. (Ecological Modelling, 2007)
The current work investigates on the applicability of a widespread bio-geochemical model (BIOME-BGC) to estimate seasonal photosynthesis and transpiration within water limited Mediterranean forest environments. The use of the model required a preliminary calibration phase, aimed at setting its ecophysiological parameters to properly simulate the behavior of three Mediterranean species (Quercus ilex L., Quercus cerris L. and Pinus pinaster Ait.). For each of these species, the calibration of BIOME-BGC was performed by adjusting the monthly gross primary productivity (GPP) estimates of 10 forest plots to those of a simpliﬁed parametric model, C-Fix, which is based on the use of satellite and ancillary data. In particular, BIOME-BGC was run modifying the eco-physiological parameters controlling stomatal conductance, in order to identify the best model conﬁgurations to reproduce the spatial, intraand inter-annual GPP variations simulated by C-Fix. Next, the fraction of leaf nitrogen in Rubisco was adjusted to ﬁt also the magnitudes of the C-Fix GPP estimates. The subsequent testing phase consisted of applying the original and calibrated versions of BIOME-BGC in independent forest sites where the three species considered were dominant and for which ﬁeld measurements of photosynthesis and transpiration were available. In all cases the use of the calibrated BIOME-BGC versions led to notably improve the GPP and transpiration estimation accuracy of the original model. The results obtained encourage the operational application of BIOME-BGC in Mediterranean forest environments and indicate a possible strategy to integrate its functions with those of C-Fix.
Keywords: BIOME-BGC; C-Fix; GPP; mediterranean forest; monitoring; Spot-VGT

Application of BIOME-BGC to simulate Mediterranean forest processes - Chiesi, M; Maselli, F; Moriondo, M; Fibbi, L; Bindi, M; Running, S W (Ecological Modelling, 2007)
The current work investigates on the applicability of a widespread bio-geochemical model (BIOME-BGC) to estimate seasonal photosynthesis and transpiration within water limited Mediterranean forest environments. The use of the model required a preliminary calibration phase, aimed at setting its ecophysiological parameters to properly simulate the behavior of three Mediterranean species (Quercus ilex L., Quercus cerris L. and Pinus pinaster Ait.). For each of these species, the calibration of BIOME-BGC was performed by adjusting the monthly gross primary productivity (GPP) estimates of 10 forest plots to those of a simpliﬁed parametric model, C-Fix, which is based on the use of satellite and ancillary data. In particular, BIOME-BGC was run modifying the eco-physiological parameters controlling stomatal conductance, in order to identify the best model conﬁgurations to reproduce the spatial, intraand inter-annual GPP variations simulated by C-Fix. Next, the fraction of leaf nitrogen in Rubisco was adjusted to ﬁt also the magnitudes of the C-Fix GPP estimates. The subsequent testing phase consisted of applying the original and calibrated versions of BIOME-BGC in independent forest sites where the three species considered were dominant and for which ﬁeld measurements of photosynthesis and transpiration were available. In all cases the use of the calibrated BIOME-BGC versions led to notably improve the GPP and transpiration estimation accuracy of the original model. The results obtained encourage the operational application of BIOME-BGC in Mediterranean forest environments and indicate a possible strategy to integrate its functions with those of C-Fix.
Keywords: BIOME-BGC; C-Fix; GPP; mediterranean forest; monitoring; Spot-VGT

Assessing the risk caused by ground level ozone to European forest trees: a case study in pine, beech and oak across different climate regions. - Emberson, Lisa D.; Büker, Patrick; Ashmore, Mike R. (Environmental pollution (Barking, Essex : 1987), 2007)
Two different indices have been proposed for estimation of the risk caused to forest trees across Europe by ground-level ozone, (i) the concentration based AOT40 index (Accumulated Over a Threshold of 40 ppb) and (ii) the recently developed flux based AFstY index (Accumulated stomatal Flux above a flux threshold Y). This paper compares the AOT40 and AFstY indices for three forest trees species at different locations in Europe. The AFstY index is estimated using the DO(3)SE (Deposition of Ozone and Stomatal Exchange) model parameterized for Scots pine (Pinus sylvestris), beech (Fagus sylvatica) and holm oak (Quercus ilex). The results show a large difference in the perceived O(3) risk when using AOT40 and AFstY indices both between species and regions. The AOT40 index shows a strong north-south gradient across Europe, whereas there is little difference between regions in the modelled values of AFstY. There are significant differences in modelled AFstY between species, which are predominantly determined by differences in the timing and length of the growing season, the periods during which soil moisture deficit limits stomatal conductance, and adaptation to soil moisture stress. This emphasizes the importance of defining species-specific flux response variables to obtain a more accurate quantification of O(3) risk.
The following values have no corresponding Zotero field: accession-num: 17412465
Keywords: Beech (Fagus sylvatica); Critical levels; Deposition; Flux; Forests; Holm oak (Quercus ilex); Ozone; Scots pine (Pinus sylvestris); stomata

Assessing the risk caused by ground level ozone to European forest trees: a case study in pine, beech and oak across different climate regions. - Emberson, Lisa D; Büker, Patrick; Ashmore, Mike R (Environmental pollution (Barking, Essex : 1987), 2007)
Two different indices have been proposed for estimation of the risk caused to forest trees across Europe by ground-level ozone, (i) the concentration based AOT40 index (Accumulated Over a Threshold of 40 ppb) and (ii) the recently developed flux based AFstY index (Accumulated stomatal Flux above a flux threshold Y). This paper compares the AOT40 and AFstY indices for three forest trees species at different locations in Europe. The AFstY index is estimated using the DO(3)SE (Deposition of Ozone and Stomatal Exchange) model parameterized for Scots pine (Pinus sylvestris), beech (Fagus sylvatica) and holm oak (Quercus ilex). The results show a large difference in the perceived O(3) risk when using AOT40 and AFstY indices both between species and regions. The AOT40 index shows a strong north-south gradient across Europe, whereas there is little difference between regions in the modelled values of AFstY. There are significant differences in modelled AFstY between species, which are predominantly determined by differences in the timing and length of the growing season, the periods during which soil moisture deficit limits stomatal conductance, and adaptation to soil moisture stress. This emphasizes the importance of defining species-specific flux response variables to obtain a more accurate quantification of O(3) risk.
Keywords: Beech (Fagus sylvatica); Critical levels; Deposition; Flux; Forests; Holm oak (Quercus ilex); Ozone; Scots pine (Pinus sylvestris); stomata

Avaliação da morfologia dos sistemas radicais de plantas de regeneração do sobreiro através de imagem digital - SUROVY, P; BRASIL, F; Ribeiro, N A; OLIVEIRA, M R G (Revista de Ciências Agrarias, 2007)
The purpose of this study is to compare rooting patterns, namely root systems morphology of trees planted from seedlings with root systems morphology of seeded trees. The evolution of root systems can influence growth in future therefore it is important to monitor it. Data was collected in a stand installed in 1997. The evaluation of the root morphology was done using digital image analysis. Root system morphology and distribution of roots in different horizons was evaluated in eight trenches (4 trees planted + 4 trees seeded). The results show significant differences showing planted trees larger root area than seeded trees. It wasn’t found significant differences in the root system shape between planted and seeded trees.

Caracterización productiva del vacuno ecológico en Andalucía - Perea Falcón, J; García, Ana; Acero, R; Valerio, Daniel; Rodríguez, V (Arch. Zootec, 2007)
The structure of organic beef cattle farms located in Andalusia have been characterised from a stratified survey including 10% of official census. Farms are specialized in raising steers and use native breeds. The mean surface of farms is 524 ha and they have 99 cows. They are multifunctional systems located in the dehesa, where cattle commonly graze alongside other species like Iberian pigs. These farms correspond to a production model in which the land is extremely important in the production of food for the cattle, using strategic or seasonal food supplementation in periods of shortage. Average stocking is 0.43 animals/ha, lower than those proposed by Orden de 4 de febrero del 2004 (Consejería de Agricultura y Pesca), corresponding to a farming activity adapted to the environment. Likewise, the mean productivity of these farms is scarce (with an index of commercial calves of 80% and a mortality rate of 5.26%). These farms have a commercial target where the non-familiar workforce predominates, and the workforce amounts to 1.56 AWU per farm. These farms sell all calves after weaning to livestock traders, who take them to other regions for conventional fattening until slaughter. It is necessary to develop organic commercial trails to guarantee the future of the sector.
Keywords: Beef aptitude; Extensive systems; Organic farming

Caracterización productiva del vacuno ecológico en Andalucía - Perea Falcón, J.; García, Ana; Acero, R.; Valerio, Daniel; Rodríguez, V. (Arch. Zootec, 2007)
The structure of organic beef cattle farms located in Andalusia have been characterised from a stratified survey including 10% of official census. Farms are specialized in raising steers and use native breeds. The mean surface of farms is 524 ha and they have 99 cows. They are multifunctional systems located in the dehesa, where cattle commonly graze alongside other species like Iberian pigs. These farms correspond to a production model in which the land is extremely important in the production of food for the cattle, using strategic or seasonal food supplementation in periods of shortage. Average stocking is 0.43 animals/ha, lower than those proposed by Orden de 4 de febrero del 2004 (Consejería de Agricultura y Pesca), corresponding to a farming activity adapted to the environment. Likewise, the mean productivity of these farms is scarce (with an index of commercial calves of 80% and a mortality rate of 5.26%). These farms have a commercial target where the non-familiar workforce predominates, and the workforce amounts to 1.56 AWU per farm. These farms sell all calves after weaning to livestock traders, who take them to other regions for conventional fattening until slaughter. It is necessary to develop organic commercial trails to guarantee the future of the sector.
Keywords: Beef aptitude; Extensive systems; Organic farming

Catálogo florístico del Macizo de Líbar (Parques naturales Sierra de Grazalema y Los Alcornocales, Málaga-Cádiz, España) - Becerra Parra, M; Robles Domínguez, E (Acta Botanica Malacitana, 2007)
The Mountain of Líbar is one of the most important ranges of the mountainous area of Ronda and Western Andalusia. Its main orographic characteristic is the presence of two mountainous alignments that delimit a great intramountainous depression denominated Llanos de Líbar. The Quercus rotundifolia wood is the main vegetation in limestone lands, whereas the Q. suber forest is dominant in sandstone zones. Other plants communities present in this area are dominated by Q. faginea, Olea europaea, Ceratonia siliqua, Fraxinus angustifolia, Ulmus minor, Nerium oleander and other shrublands. This is one of the zones with highest rainfall in the Iberian Peninsula and with mild temperatures, although in the summits, the annual average temperature, decreases near 10 ºC. In order to carry out the botanical study, samplings have been made during five years, in addition to a bibliographical revision and review of biodiversity databases. The botanical catalogue of Líbar is composed by 826 species, 128 are endemic species with different distribution area. Linaria platycalyx, Reseda gayana subsp. undata or Saxifraga bourgeana are endemic from the area of Ronda. 13 species are protected according to the Law of Wild Flora and Fauna of Andalusia and 32 species are included in the plants Red List of Andalusia.
Keywords: Cádiz.; Catalogue; Flora; Los Alcornocales; Macizo de Líbar; Málaga; Sierra de Grazalema

Catálogo florístico del Macizo de Líbar (Parques naturales Sierra de Grazalema y Los Alcornocales, Málaga-Cádiz, España) - Becerra Parra, M.; Robles Domínguez, E. (Acta Botanica Malacitana, 2007)
The Mountain of Líbar is one of the most important ranges of the mountainous area of Ronda and Western Andalusia. Its main orographic characteristic is the presence of two mountainous alignments that delimit a great intramountainous depression denominated Llanos de Líbar. The Quercus rotundifolia wood is the main vegetation in limestone lands, whereas the Q. suber forest is dominant in sandstone zones. Other plants communities present in this area are dominated by Q. faginea, Olea europaea, Ceratonia siliqua, Fraxinus angustifolia, Ulmus minor, Nerium oleander and other shrublands. This is one of the zones with highest rainfall in the Iberian Peninsula and with mild temperatures, although in the summits, the annual average temperature, decreases near 10 ºC. In order to carry out the botanical study, samplings have been made during five years, in addition to a bibliographical revision and review of biodiversity databases. The botanical catalogue of Líbar is composed by 826 species, 128 are endemic species with different distribution area. Linaria platycalyx, Reseda gayana subsp. undata or Saxifraga bourgeana are endemic from the area of Ronda. 13 species are protected according to the Law of Wild Flora and Fauna of Andalusia and 32 species are included in the plants Red List of Andalusia.
Keywords: Cádiz.; Catalogue; Flora; Los Alcornocales; Macizo de Líbar; Málaga; Sierra de Grazalema

The Cd(II)-binding abilities of recombinant Quercus suber metallothionein: bridging the gap between phytochelatins and metallothioneins. - Domenech, Jordi; Orihuela, Ruben; Mir, Gisela; Molinas, Marisa; Atrian, Silvia; Capdevila, Merce (Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry, 2007)
In this work, we have analyzed both at stoichiometric and at conformational level the Cd(II)-binding features of a type 2 plant metallothionein (MT) (the cork oak, Quercus suber, QsMT). To this end four peptides, the wild-type QsMT and three constructs previously engineered to characterize its Zn(II)- and Cu(I)-binding behaviour, were heterologously produced in Escherichia coli cultures supplemented with Cd(II), and the corresponding complexes were purified up to homogeneity. The Cd(II)-binding ability of these recombinant peptides was determined through the chemical, spectroscopic and spectrometric characterization of the recovered clusters. Recombinant synthesis of the four QsMT peptides in cadmium-rich media rendered complexes with a higher metal content than those obtained from zinc-supplemented cultures and, consequently, the recovered Cd(II) species are nonisostructural to those of Zn(II). Also of interest is the fact that three out of the four peptides yielded recombinant preparations that included S(2-)-containing Cd(II) complexes as major species. Subsequently, the in vitro Zn(II)/Cd(II) replacement reactions were studied, as well as the in vitro acid denaturation and S(2-) renaturation reactions. Finally, the capacity of the four peptides for preventing cadmium deleterious effects in yeast cells was tested through complementation assays. Consideration of all the results enables us to suggest a hairpin folding model for this typical type 2 plant Cd(II)-MT complex, as well as a nonnegligible role of the spacer in the detoxification function of QsMT towards cadmium.
Keywords: cadmium; Cadmium: chemistry; Cadmium–His binding; Drug; Glutathione; Metabolic Detoxication; metallothionein; Metallothionein: chemistry; Metallothionein: metabolism; Phytochelatins; Plant metallothionein; Plant Proteins; Plant Proteins: chemistry; Plant Proteins: metabolism; Protein Binding; Protein Conformation; Quercus; Recombinant Proteins; Sulfide ligands; yeast complementation

The Cd(II)-binding abilities of recombinant Quercus suber metallothionein: bridging the gap between phytochelatins and metallothioneins. - Domenech, Jordi; Orihuela, Ruben; Mir, Gisela; Molinas, Marisa; Atrian, Silvia; Capdevila, Merce (Journal of biological inorganic chemistry : JBIC : a publication of the Society of Biological Inorganic Chemistry, 2007)
In this work, we have analyzed both at stoichiometric and at conformational level the Cd(II)-binding features of a type 2 plant metallothionein (MT) (the cork oak, Quercus suber, QsMT). To this end four peptides, the wild-type QsMT and three constructs previously engineered to characterize its Zn(II)- and Cu(I)-binding behaviour, were heterologously produced in Escherichia coli cultures supplemented with Cd(II), and the corresponding complexes were purified up to homogeneity. The Cd(II)-binding ability of these recombinant peptides was determined through the chemical, spectroscopic and spectrometric characterization of the recovered clusters. Recombinant synthesis of the four QsMT peptides in cadmium-rich media rendered complexes with a higher metal content than those obtained from zinc-supplemented cultures and, consequently, the recovered Cd(II) species are nonisostructural to those of Zn(II). Also of interest is the fact that three out of the four peptides yielded recombinant preparations that included S(2-)-containing Cd(II) complexes as major species. Subsequently, the in vitro Zn(II)/Cd(II) replacement reactions were studied, as well as the in vitro acid denaturation and S(2-) renaturation reactions. Finally, the capacity of the four peptides for preventing cadmium deleterious effects in yeast cells was tested through complementation assays. Consideration of all the results enables us to suggest a hairpin folding model for this typical type 2 plant Cd(II)-MT complex, as well as a nonnegligible role of the spacer in the detoxification function of QsMT towards cadmium.
The following values have no corresponding Zotero field: accession-num: 17503092
Keywords: cadmium; Cadmium: chemistry; Cadmium–His binding; Drug; Glutathione; Metabolic Detoxication; metallothionein; Metallothionein: chemistry; Metallothionein: metabolism; Phytochelatins; Plant metallothionein; Plant Proteins; Plant Proteins: chemistry; Plant Proteins: metabolism; Protein Binding; Protein Conformation; Quercus; Recombinant Proteins; Sulfide ligands; yeast complementation

Comparative Typology in Six European Lowâ€Intensity Systems of Grassland Management - Caballero, Rafael; Riseth JÅand Labba, Niklas (Advances in Agronomy, 2007)
management with varying degrees of arrangements in different European countries and landscapes. These large-scale grazing systems (LSGS) are rein- deer husbandry in Northern Sapmi (Fennoscandia), sheep grazing in the Polish Tatra mountains, cattle grazing in the Swiss and German Alps, cattle, sheep, and pig grazing in Baixo Alentejo, Southern Portugal, and sedentary sheep grazing in Central Spain. These systems showed very heterogeneous organizational patterns in their way of exploiting the pastoral resources. At the same time, these LSGS showed at least some of the following weaknesses such as poor economic performance, social fragility, and structural shortcomings for proper grazing management. Lack of proper mobility of herds/flocks or accession to specific grazing grounds can be a cause of environmental hazards. The sur- veyed LSGS are mostly dependent on public handouts for survival, but succes- sive policy schemes have only showed mixed effects and, in particular study areas, clear inconsistencies in their aim to stop the general declining trend of LSGS. This research assumed that detailed system research may open the way for better-focused policy intervention, but policymakers need to take advantage of this period of support to push ahead for reforms. Recent European Union (EU) guidelines (2007–2013) on Rural Development Policy (RDP) and its operative scale of high nature value (HNV) farmland can easily fit the structure and functions of low-input grazing systems and LSGS.
The following values have no corresponding Zotero field: periodical: Advances in Agronomy electronic-resource-num: 10.1016/S0065-2113(07)96001-0
Keywords: economic performance; Grazing lands; Grazing management; grazing systems; land use; productivity (voyant)

Comparative Typology in Six European Lowâ€Intensity Systems of Grassland Management - Caballero, Rafael; Riseth JÅand Labba, Niklas (Advances in Agronomy, 2007)
management with varying degrees of arrangements in different European countries and landscapes. These large-scale grazing systems (LSGS) are rein- deer husbandry in Northern Sapmi (Fennoscandia), sheep grazing in the Polish Tatra mountains, cattle grazing in the Swiss and German Alps, cattle, sheep, and pig grazing in Baixo Alentejo, Southern Portugal, and sedentary sheep grazing in Central Spain. These systems showed very heterogeneous organizational patterns in their way of exploiting the pastoral resources. At the same time, these LSGS showed at least some of the following weaknesses such as poor economic performance, social fragility, and structural shortcomings for proper grazing management. Lack of proper mobility of herds/flocks or accession to specific grazing grounds can be a cause of environmental hazards. The sur- veyed LSGS are mostly dependent on public handouts for survival, but succes- sive policy schemes have only showed mixed effects and, in particular study areas, clear inconsistencies in their aim to stop the general declining trend of LSGS. This research assumed that detailed system research may open the way for better-focused policy intervention, but policymakers need to take advantage of this period of support to push ahead for reforms. Recent European Union (EU) guidelines (2007–2013) on Rural Development Policy (RDP) and its operative scale of high nature value (HNV) farmland can easily fit the structure and functions of low-input grazing systems and LSGS.
Keywords: economic performance; Grazing lands; Grazing management; grazing systems; land use; productivity (voyant)

Comparing the role of site disturbance and landscape properties on understory species richness in fragmented periurban Mediterranean forests - Guirado, Maria; Pino, Joan; Rodà, Ferran (Landscape Ecology, 2007)
We hypothesized that the spatial con- ﬁguration and dynamics of periurban forest patches in Barcelona (NE of Spain) played a minor role in determining plant species richness and assemblage compared to site conditions, and particularly to both direct (measured at plot level) and potential (inferred from landscape metrics) human-associated site disturbance. The presence of all understory vascular plants was recorded on 252 plots of 100 m 2 randomly selected within forest patches ranging in size from 0.25 ha to 218 ha. Species were divided into 6 groups, according to their ecology and conservation status. Site condition was assessed at plot level and included physical attributes, human-induced disturbance and Quercus spp. tree cover. Landscape structure and dynamics were assessed from patch metrics and patch history. We also calculated a set of landscape metrics related to potential human accessibility to forests. Results of multiple linear regressions indicated that the variance explained for non-forest species groups was higher than for forest species richness. Most of the main correlates corresponded to site disturbance variables related to direct human alteration, or to landscape variables associated to indirect human effects on forests: Quercus tree cover (a proxy for successional status) was the most important correlate of non-forest species richness, which decreased when Quercus tree cover increased. Human-induced disturbance was an important correlate of synanthropic and total species richness, which were higher in recently managed and in highly frequented forests. Potential human accessibility also affected the richness of most species groups. In contrast, patch size, patch shape and connectivity played a minor role, as did patch history. We conclude that human inﬂuence on species richness in periurban forests takes place on a small scale, whereas large-scale effects attributable to landscape structure and fragmentation are comparatively less important. Implications of these results for the conservation of plant species in periurban forests are discussed.
Keywords: Forest condition; Forest fragmentation; Forest patches; Human-induced disturbance; Multiple linear regressions; Patch history; Plant species richness; Synanthropic species

Comparing the role of site disturbance and landscape properties on understory species richness in fragmented periurban Mediterranean forests - Guirado, Maria; Pino, Joan; Rodà, Ferran (Landscape Ecology, 2007)
We hypothesized that the spatial con- ﬁguration and dynamics of periurban forest patches in Barcelona (NE of Spain) played a minor role in determining plant species richness and assemblage compared to site conditions, and particularly to both direct (measured at plot level) and potential (inferred from landscape metrics) human-associated site disturbance. The presence of all understory vascular plants was recorded on 252 plots of 100 m 2 randomly selected within forest patches ranging in size from 0.25 ha to 218 ha. Species were divided into 6 groups, according to their ecology and conservation status. Site condition was assessed at plot level and included physical attributes, human-induced disturbance and Quercus spp. tree cover. Landscape structure and dynamics were assessed from patch metrics and patch history. We also calculated a set of landscape metrics related to potential human accessibility to forests. Results of multiple linear regressions indicated that the variance explained for non-forest species groups was higher than for forest species richness. Most of the main correlates corresponded to site disturbance variables related to direct human alteration, or to landscape variables associated to indirect human effects on forests: Quercus tree cover (a proxy for successional status) was the most important correlate of non-forest species richness, which decreased when Quercus tree cover increased. Human-induced disturbance was an important correlate of synanthropic and total species richness, which were higher in recently managed and in highly frequented forests. Potential human accessibility also affected the richness of most species groups. In contrast, patch size, patch shape and connectivity played a minor role, as did patch history. We conclude that human inﬂuence on species richness in periurban forests takes place on a small scale, whereas large-scale effects attributable to landscape structure and fragmentation are comparatively less important. Implications of these results for the conservation of plant species in periurban forests are discussed.
Keywords: Forest condition; Forest fragmentation; Forest patches; Human-induced disturbance; Multiple linear regressions; Patch history; Plant species richness; Synanthropic species

A comprehensive assessment of multifunctional agricultural land-use systems in Spain using a multi-dimensional evaluative model - Gómez Sal, Antonio; González García, Alberto (Agriculture, Ecosystems & Environment, 2007)
European agriculture is increasingly involved in nature conservation. Careful assessment of the ecosystems created by agriculture is essential for the evaluation of the sustainability of the interaction between agriculture and these systems. We consider two main requirements for agricultural sustainability: (a) ecological integrity: the maintenance of ecosystem functionality and (b) ecological coherence: the appropriate connection between the production system and the underlying ecosystem. This viewpoint emphasizes the sustaining capacity of the ecosystem as the basis of agricultural production, independent of its conventional economic value (profitability). The application of these ideas implies the investigation of relationships between both the different functions of agriculture and the dimensions relevant for the evaluation of the sustainability of agriculture. We apply a multidimensional evaluation model to some characteristic Spanish agricultural landscapes and compare the results with contrasting reference scenarios. The value of each dimension of sustainability is assessed using a semi-quantitative procedure. Results show that strongly contrasting agricultural systems can be categorized into well-defined groups on the basis of the sustainability dimensions. These groups play an increasingly divergent role in nature conservation. This analysis contributes to the discussion of consequences of European policies on the conservation of agricultural landscapes.
Keywords: ecological coherence; ecological integrity; evaluative dimensions; scenarios; strong sustainability

Cork oak (Quercus suber L.) acorn as a substitute for barley in the diet of rabbits; Effect on In vivo digestibility, growth and carcass characteristics. J. anim - Boubaker, A. Gasmi; Abduli, H.; Lozada, M. R. M. (Journal of Animal and Veterinary Advances, 2007)
In this study 2 experiments were conducted to evaluate the feeding value of cork oak acorn as an energy source for rabbits. Experiment 1 was a digestibility trial using 20 adult rabbits (10 rabbits/group) and experiment 2 was a growth performance and carcass evaluation using 24 growing rabbits in a completely randomised design. Two diets were formulated to contain either 250 g Dry Matter (DM) barley (Barley diet) or 250 g DM oak Acorn (Acorn diet)/kg and included mainly, wheat bran, soybean meal, hay, molasses, calcium phosphate, Cu SO4 and salt. Inclusion of acorn in the diet did not result in any change in odour and fungal contamination nor in the feed intake (p>0.05). However, acorn in the diet decreased the in vivo digestibility by 10.8, 11.5 and 17.5%, respectively, for DM, Organic Matter (OM) and Crude Protein (CP). Although the rabbits fed acorn diet retained less nitrogen than those fed barley diet, they were positive in the nitrogen balance. The final live weight and daily weight gain from weaning through slaughter did not show any significant difference between rabbits fed the control diet and those fed the experimental diet. Similar carcass yield and feed conversion ratio were observed for the 2 groups. Weight of full gastrointestinal, liver, kidney and caecum were not affected (p>0.05) by the presence of acorn in the experimental diet. A more careful evaluation of the real content and digestibility of nutrients from acorn is necessary to evaluate their nutritional value before considering them as a potential feed for rabbits.
Keywords: acorn; digestibility; Growth; rabbit; tannin

Cork oak (Quercus suber L.) acorn as a substitute for barley in the diet of rabbits; Effect on In vivo digestibility, growth and carcass characteristics. J. anim - Boubaker, A Gasmi; Abduli, H; Lozada, M R M (Journal of Animal and Veterinary Advances, 2007)
In this study 2 experiments were conducted to evaluate the feeding value of cork oak acorn as an energy source for rabbits. Experiment 1 was a digestibility trial using 20 adult rabbits (10 rabbits/group) and experiment 2 was a growth performance and carcass evaluation using 24 growing rabbits in a completely randomised design. Two diets were formulated to contain either 250 g Dry Matter (DM) barley (Barley diet) or 250 g DM oak Acorn (Acorn diet)/kg and included mainly, wheat bran, soybean meal, hay, molasses, calcium phosphate, Cu SO4 and salt. Inclusion of acorn in the diet did not result in any change in odour and fungal contamination nor in the feed intake (p>0.05). However, acorn in the diet decreased the in vivo digestibility by 10.8, 11.5 and 17.5%, respectively, for DM, Organic Matter (OM) and Crude Protein (CP). Although the rabbits fed acorn diet retained less nitrogen than those fed barley diet, they were positive in the nitrogen balance. The final live weight and daily weight gain from weaning through slaughter did not show any significant difference between rabbits fed the control diet and those fed the experimental diet. Similar carcass yield and feed conversion ratio were observed for the 2 groups. Weight of full gastrointestinal, liver, kidney and caecum were not affected (p>0.05) by the presence of acorn in the experimental diet. A more careful evaluation of the real content and digestibility of nutrients from acorn is necessary to evaluate their nutritional value before considering them as a potential feed for rabbits.
Keywords: acorn; digestibility; Growth; rabbit; tannin

Cork oak (Quercus suber L.) wood growth and vessel characteristics variations in relation to climate and cork harvesting - Leal, Sofia; Nunes, Elsa; Pereira, Helena (European Journal of Forest Research, 2007)
Variations in tree ring growth of Quercus suber L. were analysed using dendrochronological techniques on cork oak discs from trees harvested in the cork producing region of Alentejo, Portugal. A tree-ring chronology containing a strong common signal and covering the period from 1970 to 1995 was build for ca. 30-year-old cork oaks never submitted to cork harvesting using 14 trees that crossdated satisfactorily out of 30 sampled trees. The tree ring indices correlated positively with September temperature (r = 0.48, P < 0.05) and very strongly with precipitation totals from previous October until current February (r = 0.82, P < 0.001) showing that the water stored in the soil during the autumn and winter months prior to the growing season has a primordial effect on the growth of the given season. The effects of cork harvesting were analysed by comparing mean ring width, mean annual vessel area, vessel density (nvessels/mm 2 ), and vessel coverage (percentage of transverse surface occupied by vessels) between three mature cork oak trees and three young trees, for the period from 1987 to 1996, corresponding to the growth between two consecutive cork removals in the case of mature trees. In 1988, 1989 and 1996 (corresponding to the ﬁrst and second years after cork removal, and 1996 to a year of cork removal), the ratios between ring widths of young versus mature trees was twice that for the rest of the period. However, an effect of cork removal indicated by eventual alterations in vessel size and distribution in the wood rings corresponding to the years 1988, 1989 and 1996 in the mature cork oaks was not observed.
Keywords: cork harvesting; Dendrochronology; Precipitation; Quercus Suber L; tree rings; wood anatomy; wood vessels

Decomposition dynamics of Myrtus communis and Quercus ilex leaf litter: Mass loss, microbial activity and quality change - Fioretto, a; Papa, S; Pellegrino, a; Fuggi, A (Applied Soil Ecology, 2007)
The patterns of microbial respiration and enzyme activity (cellulase, xylanase, laccase and peroxidase) in the leaf litter of two evergreen sclerophyll species, Myrtus communis and Quercus ilex, were compared during decay in a low shrubland and in a coppice wood in a Natural Reserve in the Mediterranean area. The two litter types had similar initial amounts of lignin, cellulose and acid-detergentsoluble substances, but the litter from M. communis had a lower N content and higher C/N ratio. In spite of this, the decomposition rate of M. communis litter was higher than for Q. ilex. Whilst no seasonal variation was observed in the rate of organic matter degradation, respiration and extractable cellulase and xylanase activities showed seasonal variation in both litter types with the highest values in winter–early spring and the lowest in summer, and showed positive correlations with water content. Peroxidase activity exhibited a seasonal pattern and was higher in Q. ilex than in M. communis, while laccase activity was higher in M. communis and increased with fungal biomass as degradation progressed. Nevertheless, no relationship was found between laccase and peroxidase activity and lignin degradation. The results obtained indicate that the seasonal alternation of moist and dry periods is the major factor inﬂuencing soil biological activity in the Mediterranean area. The occurrence of pronounced seasonal variation in litter enzyme activity prevents the determination of possible correlations with litter mass loss.
Keywords: Cellulose; Enzyme activity; Fungal biomass; Lignin; litter decomposition; Microbial respiration

Decomposition dynamics of Myrtus communis and Quercus ilex leaf litter: Mass loss, microbial activity and quality change - Fioretto, A.; Papa, S.; Pellegrino, A.; Fuggi, A. (Applied Soil Ecology, 2007)
The patterns of microbial respiration and enzyme activity (cellulase, xylanase, laccase and peroxidase) in the leaf litter of two evergreen sclerophyll species, Myrtus communis and Quercus ilex, were compared during decay in a low shrubland and in a coppice wood in a Natural Reserve in the Mediterranean area. The two litter types had similar initial amounts of lignin, cellulose and acid-detergentsoluble substances, but the litter from M. communis had a lower N content and higher C/N ratio. In spite of this, the decomposition rate of M. communis litter was higher than for Q. ilex. Whilst no seasonal variation was observed in the rate of organic matter degradation, respiration and extractable cellulase and xylanase activities showed seasonal variation in both litter types with the highest values in winter–early spring and the lowest in summer, and showed positive correlations with water content. Peroxidase activity exhibited a seasonal pattern and was higher in Q. ilex than in M. communis, while laccase activity was higher in M. communis and increased with fungal biomass as degradation progressed. Nevertheless, no relationship was found between laccase and peroxidase activity and lignin degradation. The results obtained indicate that the seasonal alternation of moist and dry periods is the major factor inﬂuencing soil biological activity in the Mediterranean area. The occurrence of pronounced seasonal variation in litter enzyme activity prevents the determination of possible correlations with litter mass loss.
Keywords: Cellulose; Enzyme activity; Fungal biomass; Lignin; litter decomposition; Microbial respiration

Descriptive analysis of the ‘relictual’ Mediterranean landscape in the Guadalquivir River valley (southern Spain): a baseline for scientific research and the development of conservation action plans - Aparicio, Abelardo (Biodiversity and Conservation, 2007)
Landscape fragmentation is ancient and severe in the countryside of the Guadalquivir river valley (Western Andalusia, Southern Spain). BIANDOCC is a project that aims to inventory all the forest patches embedded in this anthropogenic area to record quantitative, qualitative, and descriptive information about management, conservation status, vegetation physiognomy and Xoristic richness. We have characterized a ‘relictual’ landscape (t1% of habitat retention) where nearly 70% of the patches (N = 535) are owned by private landowners who manage them to harvest pine nuts, cork, and Wrewood, for coal making, cattle raising, and to a lesser extent, beekeeping and agriculture. The publicly owned patches are intensively used for recreation. As a consequence, the vegetation physiognomy and conservation status in most forest stands is impoverished, with low shrub diversity and coverage and none or very low natural tree regeneration. Furthermore, patch size, connectedness and patch fractal dimension (i.e. microhabitat diversity) are all very low. However, the botanic richness is worth mentioning: 1,032 plant taxa have been identiWed, of which 70 are catalogued in an oYcial red list, 39 are relevant chorological novelties, and one was newly described for science. Therefore, and interestingly, the remnant forest patches in the studied area can be regarded as relevant biodiversity reservoirs. The project reported here constitutes an important baseline for developing true conservation action plans and provides an opportunity to address the potential ecological and biological eVects of fragmentation to plant genes, species, populations and communities, at the regional scale of the study, which are enhanced by the emergent landscape genetics and landscape ecology analytical tools.
Keywords: Biodiversity; Connectivity; fragstats; Habitat fragmentation; habitat loss; isolation; Mediterranean vegetation

Descriptive analysis of the ‘relictual’ Mediterranean landscape in the Guadalquivir River valley (southern Spain): a baseline for scientific research and the development of conservation action plans - Aparicio, Abelardo (Biodiversity and Conservation, 2007)
Landscape fragmentation is ancient and severe in the countryside of the Guadalquivir river valley (Western Andalusia, Southern Spain). BIANDOCC is a project that aims to inventory all the forest patches embedded in this anthropogenic area to record quantitative, qualitative, and descriptive information about management, conservation status, vegetation physiognomy and Xoristic richness. We have characterized a ‘relictual’ landscape (t1% of habitat retention) where nearly 70% of the patches (N = 535) are owned by private landowners who manage them to harvest pine nuts, cork, and Wrewood, for coal making, cattle raising, and to a lesser extent, beekeeping and agriculture. The publicly owned patches are intensively used for recreation. As a consequence, the vegetation physiognomy and conservation status in most forest stands is impoverished, with low shrub diversity and coverage and none or very low natural tree regeneration. Furthermore, patch size, connectedness and patch fractal dimension (i.e. microhabitat diversity) are all very low. However, the botanic richness is worth mentioning: 1,032 plant taxa have been identiWed, of which 70 are catalogued in an oYcial red list, 39 are relevant chorological novelties, and one was newly described for science. Therefore, and interestingly, the remnant forest patches in the studied area can be regarded as relevant biodiversity reservoirs. The project reported here constitutes an important baseline for developing true conservation action plans and provides an opportunity to address the potential ecological and biological eVects of fragmentation to plant genes, species, populations and communities, at the regional scale of the study, which are enhanced by the emergent landscape genetics and landscape ecology analytical tools.
Keywords: Biodiversity; Connectivity; fragstats; Habitat fragmentation; habitat loss; isolation; Mediterranean vegetation

Development and application of bio-economic modelling to compare silvoarable, arable, and forestry systems in three European countries - a. R. Graves; Burgess, P. J. J.; Palma, J. H. N. H. N.; Herzog, F.; Moreno, G.; Bertomeu, M.; Dupraz, C.; Liagre, F.; Keesman, K.; van der Werf, W.; de Nooy, a Koeffeman; van den Briel, J. P. P.; et al. (Ecological Engineering, 2007)
Silvoarable agroforestry could promote use of trees on farms in Europe, but its likely effect on production, farm proﬁtability, and environmental services is poorly understood. Hence, from 2001 to 2005, the Silvoarable Agroforestry for Europe project developed a systematic process to evaluate the biophysical and economic performance of arable, forestry, and silvoarable systems in Spain, France, and The Netherlands. A biophysical model called “Yield-SAFE” was developed to predict long-term yields for the different systems and local statistics and expert opinion were used to derive their revenue, costs, and pre- and post-2005 grant regimes. These data were then used in an economic model called “Farm-SAFE” to predict plot- and farm-scale proﬁtability. Land equivalent ratios were greater than one, showing Yield-SAFE predicted that growing trees and crops in silvoarable systems was more productive than growing them separately. Pre-2005 grants in Spain and The Netherlands penalised silvoarable systems, but post-2005 grants were more equitable. In France, walnut and poplar silvoarable systems were consistently the most proﬁtable system under both grant regimes. In Spain, holm oak and stone pine silvoarable systems were the least proﬁtable system under pre-2005 grants, but only marginally less proﬁtable than arable systems under post-2005 grants. In The Netherlands, low timber values and the opportunity cost of losing arable land for slurry manure application made silvoarable and forestry systems uncompetitive with arable systems under both grant regimes.
Keywords: Agroforestry; Arable; Biophysical; Economics; Farm-SAFE; Forestry; Modelling; Poplar; Silvoarable; Temperate; Walnut; Yield-SAFE

Development and application of bio-economic modelling to compare silvoarable, arable, and forestry systems in three European countries - a.R. Graves; Burgess, P.J. J; Palma, J.H.N. H N; Herzog, F.; Moreno, G.; Bertomeu, M.; Dupraz, C.; Liagre, F.; Keesman, K.; van der Werf, W.; de Nooy, a. Koeffeman; van den Briel, J.P. P; et al. (Ecological Engineering, 2007)
Silvoarable agroforestry could promote use of trees on farms in Europe, but its likely effect on production, farm proﬁtability, and environmental services is poorly understood. Hence, from 2001 to 2005, the Silvoarable Agroforestry for Europe project developed a systematic process to evaluate the biophysical and economic performance of arable, forestry, and silvoarable systems in Spain, France, and The Netherlands. A biophysical model called “Yield-SAFE” was developed to predict long-term yields for the different systems and local statistics and expert opinion were used to derive their revenue, costs, and pre- and post-2005 grant regimes. These data were then used in an economic model called “Farm-SAFE” to predict plot- and farm-scale proﬁtability. Land equivalent ratios were greater than one, showing Yield-SAFE predicted that growing trees and crops in silvoarable systems was more productive than growing them separately. Pre-2005 grants in Spain and The Netherlands penalised silvoarable systems, but post-2005 grants were more equitable. In France, walnut and poplar silvoarable systems were consistently the most proﬁtable system under both grant regimes. In Spain, holm oak and stone pine silvoarable systems were the least proﬁtable system under pre-2005 grants, but only marginally less proﬁtable than arable systems under post-2005 grants. In The Netherlands, low timber values and the opportunity cost of losing arable land for slurry manure application made silvoarable and forestry systems uncompetitive with arable systems under both grant regimes.
Keywords: Agroforestry; Arable; Biophysical; Economics; Farm-SAFE; Forestry; Modelling; Poplar; Silvoarable; Temperate; Walnut; Yield-SAFE

Differences in land cover interpretation in landscapes rich in cover gradients: reflections based on the montado of South Portugal - Doorn, Anne M; Pinto Correia, Teresa (Agroforestry Systems, 2007)
This paper contributes to the discussion on current issues in methodologies of mapping land cover in the agro-silvo-pastoral landscapes of the Mediterranean. These landscapes, characterized by intermixed land use and indeÞnite boundaries, require particular attention in applying the patch-corridor-matrix model when classifying patches and their delineation. In a case study area in southeast Portugal, mainly characterized by agro-silvo pastoral systems, the land cover for 1990 has been mapped. The paper discusses the consequences of the complexity of some Mediterranean land use systems for land cover mapping dealing with detailed landscape dynamics. Within this scope a land cover mapping project in a small case study area is compared with the mapping undertaken within a national land cover database. Both studies were carried out on the same scale and through visual interpretation of aerial photographs. Differences in land cover classiÞcation and allocation are explored using matrix with levels of agreement. Recommendations for future land cover mapping projects are: the application of fuzzy approaches to land cover mapping in agro-silvo-pastoral landscapes should be explored and land cover classiÞcations should be standardized in order to enhance consistency between databases. On the other hand, the fuzziness of the boundaries in this kind of landscapes is inherent to the system and should be accepted as such. The accompanying uncertainties should be taken into account when undertaking landscape analysis on the basis of land cover data.
Keywords: land cover classification; montado/dehesa; thematic cartography; visual aerial photo interpretation

Differences in land cover interpretation in landscapes rich in cover gradients: reflections based on the montado of South Portugal - Doorn, Anne M.; Pinto Correia, Teresa (Agroforestry Systems, 2007)
This paper contributes to the discussion on current issues in methodologies of mapping land cover in the agro-silvo-pastoral landscapes of the Mediterranean. These landscapes, characterized by intermixed land use and indeÞnite boundaries, require particular attention in applying the patch-corridor-matrix model when classifying patches and their delineation. In a case study area in southeast Portugal, mainly characterized by agro-silvo pastoral systems, the land cover for 1990 has been mapped. The paper discusses the consequences of the complexity of some Mediterranean land use systems for land cover mapping dealing with detailed landscape dynamics. Within this scope a land cover mapping project in a small case study area is compared with the mapping undertaken within a national land cover database. Both studies were carried out on the same scale and through visual interpretation of aerial photographs. Differences in land cover classiÞcation and allocation are explored using matrix with levels of agreement. Recommendations for future land cover mapping projects are: the application of fuzzy approaches to land cover mapping in agro-silvo-pastoral landscapes should be explored and land cover classiÞcations should be standardized in order to enhance consistency between databases. On the other hand, the fuzziness of the boundaries in this kind of landscapes is inherent to the system and should be accepted as such. The accompanying uncertainties should be taken into account when undertaking landscape analysis on the basis of land cover data.
Keywords: land cover classification; montado/dehesa; thematic cartography; visual aerial photo interpretation

Diplofuranones A and B , two further new 4-monosubstituted 2 ( 3H ) -dihydrofuranones produced by Diplodia corticola , a fungus pathogen of cork oak - Evidente, Antonio; Andolfi, Anna; Fiore, Michele; Spanu, Emanuela (ARKIVOC, 2007)
Two new 4-monosubstituted 2(3H)-dihydrofuranones, named diplofuranones A and B, were isolated from liquid cultures of Diplodia corticola, a plant pathogenic fungus causing a canker disease of cork oak (Quercus suber L.). The same fungus also produces several metabolites such as the diplopyrone, the (3S,4R)-trans- and the (3R,4R)-cis-4-hydroxymellein, the sapinofuranone B and its (S,S)-enantiomer, the well known sphaeropsidins A-C, and the diplobifuranylones A and B. The diplofuranones A and B were characterised, using spectroscopic (essentially NMR and MS techniques) methods, as the 4-[(1E,3E)-5-hydroxyhexadienyl]butan-4-olide and its corresponding 3,4-dihydro side chain derivative. The stereochemistry of the stereogenic secondary hydroxylated carbon of the side chain of diplofuranone A was determined by application of Mosher’s method and proved to be R. Diplofuranone A tested at 0.2 mg mL-1 on non-host plant did not show phytotoxic activity.
Keywords: canker disease; Cork oak; Diplodia corticola; phytotoxic metabolites; Quercus suber L.

Diplofuranones A and B , two further new 4-monosubstituted 2 ( 3H ) -dihydrofuranones produced by Diplodia corticola , a fungus pathogen of cork oak - Evidente, Antonio; Andolfi, Anna; Fiore, Michele; Spanu, Emanuela (ARKIVOC, 2007)
Two new 4-monosubstituted 2(3H)-dihydrofuranones, named diplofuranones A and B, were isolated from liquid cultures of Diplodia corticola, a plant pathogenic fungus causing a canker disease of cork oak (Quercus suber L.). The same fungus also produces several metabolites such as the diplopyrone, the (3S,4R)-trans- and the (3R,4R)-cis-4-hydroxymellein, the sapinofuranone B and its (S,S)-enantiomer, the well known sphaeropsidins A-C, and the diplobifuranylones A and B. The diplofuranones A and B were characterised, using spectroscopic (essentially NMR and MS techniques) methods, as the 4-[(1E,3E)-5-hydroxyhexadienyl]butan-4-olide and its corresponding 3,4-dihydro side chain derivative. The stereochemistry of the stereogenic secondary hydroxylated carbon of the side chain of diplofuranone A was determined by application of Mosher’s method and proved to be R. Diplofuranone A tested at 0.2 mg mL-1 on non-host plant did not show phytotoxic activity.
Keywords: canker disease; Cork oak; Diplodia corticola; phytotoxic metabolites; Quercus suber L.

Diversidade funcional em sistemas de montado : fluxo de nutrientes em Quercus rotundifolia Lam . Functional diversity in “ montado ” systems : nutrients fluxes in Quercus - Nunes, J D; Gazarini, L; Madeira, M (Revista de Ciências Agrárias, 2007)
Nutrient cycling in Quercus rotundifolia Lam. systems, regarding precipitation was studied at Évora (Southern Portugal), since November of 1996 until December of 2000. The amounts of gross rainfall, throughfall (at different distances from the tree trunk) and stemflow were measured continuously and samples for chemical analysis were collected weekly. The concentration of nutrients was higher in the throughfall than in the gross rainfall, especially in the areas closer to the tree trunk. Nutrients transferred to soil, through bulk rainfall, throughfall and stemflow were quantified. The highest concentration of nutrients was observed in the stemflow water. Soil physical and chemical characteristics, underneath and outside Quercus rotundifolia crowns, were studied in areas where trees commonly are wide spaced. The amounts of the forest floor litter layer were also evaluated. Soil physical and chemical characteristics showed in general a positive effect with tree presence. Nitrogen transformation was examined under and outside the influence of the tree canopies. Nitrogen availability was higher in the soil of under crowns areas.

Diversidade funcional em sistemas de montado : fluxo de nutrientes em Quercus rotundifolia Lam . Functional diversity in “ montado ” systems : nutrients fluxes in Quercus - Nunes, J. D.; Gazarini, L.; Madeira, M. (Revista de Ciências Agrárias, 2007)
Nutrient cycling in Quercus rotundifolia Lam. systems, regarding precipitation was studied at Évora (Southern Portugal), since November of 1996 until December of 2000. The amounts of gross rainfall, throughfall (at different distances from the tree trunk) and stemflow were measured continuously and samples for chemical analysis were collected weekly. The concentration of nutrients was higher in the throughfall than in the gross rainfall, especially in the areas closer to the tree trunk. Nutrients transferred to soil, through bulk rainfall, throughfall and stemflow were quantified. The highest concentration of nutrients was observed in the stemflow water. Soil physical and chemical characteristics, underneath and outside Quercus rotundifolia crowns, were studied in areas where trees commonly are wide spaced. The amounts of the forest floor litter layer were also evaluated. Soil physical and chemical characteristics showed in general a positive effect with tree presence. Nitrogen transformation was examined under and outside the influence of the tree canopies. Nitrogen availability was higher in the soil of under crowns areas.

Driving competitive and facilitative interactions in oak dehesas through management practices - Moreno Marcos, G; Obrador, J J; García, E; Cubera, E; Montero, M J; Pulido, F; Dupraz, C (Agroforestry Systems, 2007)
Dehesas are extant multi-purpose agroforestry systems that consist of a mosaic of widely-spaced scattered oaks (Quercus ilex L.) combined with crops, pasture or shrubs. We aimed to clarify the role of trees in dehesas of CW Spain focussed on the analysis of treeunderstorey interactions. Spatial variability of resources (light, soil moisture and fertility), microclimate, ﬁne roots of both herbaceous plants and trees and forage yield was measured. Additionally, we compared the nutritional and physiological status, growth and acorn production of oaks in cropped (fodder crop), grazed (native grasses) and encroached (woody understorey) dehesa plots. Signiﬁcant light interception by trees was limited to the close vicinity of the trees, with very low reduction away from them. Both microclimate and soil fertility improved signiﬁ- cantly in the trees vicinity, irrespective of soil management. Soil moisture varied very few with distance from the trees, as a result of the extended root system of oaks. Root systems of trees and herbs did not overlap to a great extent. Crop production was higher beneath trees than beyond the trees in unfertilised plots and foliar nutrient content of oaks did not increase signiﬁcantly with crop fertilisation, indicating that trees and crops hardly compete for nutrients. Moreover, trees beneﬁted from the crop or pasture management: trees featured a signiﬁcantly improved nutritional and physiological status, a faster growth and a higher fruit productivity than trees growing in encroached or forest plots.
Keywords: acorn production; forage yield; light; microclimate; root system; soil resources

Driving competitive and facilitative interactions in oak dehesas through management practices - Moreno Marcos, G.; Obrador, J. J.; García, E.; Cubera, E.; Montero, M. J.; Pulido, F.; Dupraz, C. (Agroforestry Systems, 2007)
Dehesas are extant multi-purpose agroforestry systems that consist of a mosaic of widely-spaced scattered oaks (Quercus ilex L.) combined with crops, pasture or shrubs. We aimed to clarify the role of trees in dehesas of CW Spain focussed on the analysis of treeunderstorey interactions. Spatial variability of resources (light, soil moisture and fertility), microclimate, ﬁne roots of both herbaceous plants and trees and forage yield was measured. Additionally, we compared the nutritional and physiological status, growth and acorn production of oaks in cropped (fodder crop), grazed (native grasses) and encroached (woody understorey) dehesa plots. Signiﬁcant light interception by trees was limited to the close vicinity of the trees, with very low reduction away from them. Both microclimate and soil fertility improved signiﬁ- cantly in the trees vicinity, irrespective of soil management. Soil moisture varied very few with distance from the trees, as a result of the extended root system of oaks. Root systems of trees and herbs did not overlap to a great extent. Crop production was higher beneath trees than beyond the trees in unfertilised plots and foliar nutrient content of oaks did not increase signiﬁcantly with crop fertilisation, indicating that trees and crops hardly compete for nutrients. Moreover, trees beneﬁted from the crop or pasture management: trees featured a signiﬁcantly improved nutritional and physiological status, a faster growth and a higher fruit productivity than trees growing in encroached or forest plots.
Keywords: acorn production; forage yield; light; microclimate; root system; soil resources

Drying and wetting of Mediterranean soils stimulates decomposition and carbon dioxide emission: the “Birch effect” - Jarvis, Paul; Rey, Ana; Petsikos, Charalampos; Wingate, Lisa; Rayment, Mark; Pereira, João; Banza, João; David, Jorge; Miglietta, Franco; Borghetti, Marco; Manca, Giovanni; Valentini, Riccardo (Tree Physiology, 2007)
Observations on the net carbon exchange of forests in the European Mediterranean region, measured recently by the eddy covariance method, have revived interest in a phenomenon first characterized on agricultural and forest soils in East Africa in the 1950s and 1960s by H. F. Birch and now often referred to as the “Birch effect.” When soils become dry during summer because of lack of rain, as is common in regions with Mediterranean climate, or are dried in the laboratory in controlled conditions, and are then rewetted by precipitation or irrigation, there is a burst of decomposition, mineralization and release of inorganic nitrogen and CO2. In forests in Mediterranean climates in southern Europe, this effect has been observed with eddy covariance techniques and soil respiration chambers at the stand and small plot scales, respectively. Following the early work of Birch, laboratory incubations of soils at controlled temperatures and water contents have been used to characterize CO2 release following the rewetting of dry soils. A simple empirical model based on laboratory incubations demonstrates that the amount of carbon mineralized over one year can be predicted from soil temperature and precipitation regime, provided that carbon lost as CO2 is taken into account. We show that the amount of carbon returned to the atmosphere following soil rewetting can reduce significantly the annual net carbon gain by Mediterranean forests.
10.1093/treephys/27.7.92910.1093/treephys/27.7.929
Keywords: carbon balance; carbon mineralization rates; Mediterranean climate; mediterranean forest; rain pulse; soil rewetting; Soil temperature; soil water; summer rainfall events

Drying and wetting of Mediterranean soils stimulates decomposition and carbon dioxide emission: the “Birch effect” - Jarvis, Paul; Rey, Ana; Petsikos, Charalampos; Wingate, Lisa; Rayment, Mark; Pereira, João; Banza, João; David, Jorge; Miglietta, Franco; Borghetti, Marco; Manca, Giovanni; Valentini, Riccardo (Tree Physiology, 2007)
Observations on the net carbon exchange of forests in the European Mediterranean region, measured recently by the eddy covariance method, have revived interest in a phenomenon first characterized on agricultural and forest soils in East Africa in the 1950s and 1960s by H. F. Birch and now often referred to as the “Birch effect.” When soils become dry during summer because of lack of rain, as is common in regions with Mediterranean climate, or are dried in the laboratory in controlled conditions, and are then rewetted by precipitation or irrigation, there is a burst of decomposition, mineralization and release of inorganic nitrogen and CO2. In forests in Mediterranean climates in southern Europe, this effect has been observed with eddy covariance techniques and soil respiration chambers at the stand and small plot scales, respectively. Following the early work of Birch, laboratory incubations of soils at controlled temperatures and water contents have been used to characterize CO2 release following the rewetting of dry soils. A simple empirical model based on laboratory incubations demonstrates that the amount of carbon mineralized over one year can be predicted from soil temperature and precipitation regime, provided that carbon lost as CO2 is taken into account. We show that the amount of carbon returned to the atmosphere following soil rewetting can reduce significantly the annual net carbon gain by Mediterranean forests.
10.1093/treephys/27.7.929
Keywords: carbon balance; carbon mineralization rates; Mediterranean climate; mediterranean forest; rain pulse; soil rewetting; Soil temperature; soil water; summer rainfall events

Ecological patterns of Tuber melanosporum and different Quercus Mediterranean forests: Quantitative production of truffles, burn sizes and soil studies - Garcia-Montero, Luis G.; Manjon, Jose L.; Pascual, Cristina; García-Abril, Antonio (Forest Ecology and Management, 2007)
Most studies on Tuber melanosporum fail to supply statistical data on carpophore production and other quantitative data associated with trufﬂe ecology, such as the development of its burns (trufﬂe production sites). During 7 years, we studied 208 burns associated with Quercus ilex subsp. ballota, Q. faginea, Corylus avellana and Tilia platyphyllos in the centre of the Iberian Peninsula. The results showed that burn size is a very signiﬁcant factor as it accounts for 38% of the variance in carpophore production. However, no signiﬁcant difference in the size of burns was observed between ﬁve types of wood, although signiﬁcant variability in carpophore production existed between these wood types. Furthermore, statistical analysis shows that a high concentration of active carbonate in the soil accounts for up to 51% of the variance in T. melanosporum burn size. The ecological conditions of burns cause elevated concentrations of active carbonate and exchangeable Ca 2+ , and T. melanosporum activity and burn size are simultaneously favoured by a high concentration of both factors, which suggests a feedback process. These results may indicate a possible application for the use of calcareous amendments in natural burns and trufﬂe cultivation. Moreover, we also determined the considerable trufﬂe-producing ability and mycorrhizing capacity of Quercus faginea. Although Q. faginea is a very little-known species in trufﬂe culture, the results provide support for its implementation
Keywords: active carbonate; Quercus faginea; truffle burn; truffle production; truffle soil; Tuber melanosporum

Ecological patterns of Tuber melanosporum and different Quercus Mediterranean forests: Quantitative production of truffles, burn sizes and soil studies - Garcia-Montero, Luis G.; Manjon, Jose L.; Pascual, Cristina; García-Abril, Antonio (Forest Ecology and Management, 2007)
Most studies on Tuber melanosporum fail to supply statistical data on carpophore production and other quantitative data associated with trufﬂe ecology, such as the development of its burns (trufﬂe production sites). During 7 years, we studied 208 burns associated with Quercus ilex subsp. ballota, Q. faginea, Corylus avellana and Tilia platyphyllos in the centre of the Iberian Peninsula. The results showed that burn size is a very signiﬁcant factor as it accounts for 38% of the variance in carpophore production. However, no signiﬁcant difference in the size of burns was observed between ﬁve types of wood, although signiﬁcant variability in carpophore production existed between these wood types. Furthermore, statistical analysis shows that a high concentration of active carbonate in the soil accounts for up to 51% of the variance in T. melanosporum burn size. The ecological conditions of burns cause elevated concentrations of active carbonate and exchangeable Ca 2+ , and T. melanosporum activity and burn size are simultaneously favoured by a high concentration of both factors, which suggests a feedback process. These results may indicate a possible application for the use of calcareous amendments in natural burns and trufﬂe cultivation. Moreover, we also determined the considerable trufﬂe-producing ability and mycorrhizing capacity of Quercus faginea. Although Q. faginea is a very little-known species in trufﬂe culture, the results provide support for its implementation
Keywords: active carbonate; Quercus faginea; truffle burn; truffle production; truffle soil; Tuber melanosporum

Economic and management characterization of dehesa farms: implications for their sustainability - Gaspar, P; Mesías, F J; Escribano, M; Rodriguez de Ledesma, A; Pulido, F (Agroforestry Systems, 2007)
Dehesa agroforestry systems occupy around 6 million ha in the Iberian Peninsula. Their economic and environmental sustainability depends on the maintenance of the extensive livestock farms which created this typical ecosystem. This work analyzes dehesa farms in the Extremadura region (SW Spain) using technical and economic indicators of 69 randomly selected holdings. Principal component analysis (PCA) allowed us to establish a valid model explaining 65.8% of the variance. The two principal components having most weight were Iberian pig production (explaining 20% of the variance of the model), and which ruminant species were raised on the farm (15% of the variance). A cluster analysis distinguished ﬁve types of farms: sheep farms at high and low stocking rates, beef cattle farms, wooded farms with mixed livestock, and farms with a high level of cropping activity. The most proﬁtable farms were those with either high overall livestock density or a high level of Iberian pig production. While high stocking density has historically attracted high levels of subsidy, production of Iberian pigs was proﬁtable because of the high value of the product. In the light of CAP reform, Iberian pig production seems the most readily sustainable type of farming for the dehesa system.
Keywords: cluster analysis; Farm typology; Livestock farming systems; Principal component analysis; Rangeland management

Economic and management characterization of dehesa farms: implications for their sustainability - Gaspar, P.; Mesías, F. J.; Escribano, M.; Rodríguez de Ledesma, A.; Pulido, F. (Agroforestry Systems, 2007)
Dehesa agroforestry systems occupy around 6 million ha in the Iberian Peninsula. Their economic and environmental sustainability depends on the maintenance of the extensive livestock farms which created this typical ecosystem. This work analyzes dehesa farms in the Extremadura region (SW Spain) using technical and economic indicators of 69 randomly selected holdings. Principal component analysis (PCA) allowed us to establish a valid model explaining 65.8% of the variance. The two principal components having most weight were Iberian pig production (explaining 20% of the variance of the model), and which ruminant species were raised on the farm (15% of the variance). A cluster analysis distinguished ﬁve types of farms: sheep farms at high and low stocking rates, beef cattle farms, wooded farms with mixed livestock, and farms with a high level of cropping activity. The most proﬁtable farms were those with either high overall livestock density or a high level of Iberian pig production. While high stocking density has historically attracted high levels of subsidy, production of Iberian pigs was proﬁtable because of the high value of the product. In the light of CAP reform, Iberian pig production seems the most readily sustainable type of farming for the dehesa system.
Keywords: cluster analysis; Farm typology; Livestock farming systems; Principal component analysis; Rangeland management

Effect of land-use on soil water dynamic in dehesas of Central–Western Spain - Cubera, Elena; Moreno, Gerardo (Catena, 2007)
Dehesa ecosystems are open woodlands with scattered oak trees as their main component. As a result of differing land-uses, the structure of vegetation found within dehesas varies between: (i) oak trees and intercropped cereals (cropped), (ii) oak trees and native grass vegetation (grazed), and (iii) oak trees with abundant understorey shrubs (encroached). The aim of this study is to investigate whether land-use influences the water dynamics of dehesas by measuring available soil water content (AWC) in the upper 250 cm of the soil at different distances from tree trunks (maximum 30 m) at four Quercus ilex dehesas in Central–Western Spain. The technique used was Time Domain Reflectometry and the study was undertaken between May of 2002 and December of 2005. Leaf water potential (Ψ) was also measured on trees at one site by mean of a pressure chamber. Within the upper meter of the soil, it appears that trees, grasses and shrubs extracted soil water resources in a similar way from both beneath and beyond the tree canopy. However, encroached plots in general showed lower average AWC values than cropped or grazed plots (3.7, 5.6, and 6.2% in encroached, cropped and grazed, respectively). Cereal crops do not compete more strongly than grasses with trees for available soil water resources. The similar Ψ values found at cropped and grazed plots supported these results. From our results, it could be hypothesized that ploughed dehesas could facilitate soil re-watering in the plots with pronounced slopes. The decrease of AWC values at encroached plots with respect to the cropped and grazed plots was found mostly beyond the tree trunk at deeper soil layers, indicating that shrubs use water partly not accessible to trees. The presence of an understory of shrubs seems to have slightly increased the water constraints on trees during the summer period (Ψd values of −0.5, −0.5, and −0.8 MPa in cropped, grazed, and encroached plots, respectively). In cropped and grazed plots, an important amount of water seems to have remained unused for trees and grasses.
Keywords: available water content; cultivation; Encroachment; fertilisation; Land-use

Effect of land-use on soil water dynamic in dehesas of Central–Western Spain - Cubera, Elena; Moreno, Gerardo (Catena, 2007)
Dehesa ecosystems are open woodlands with scattered oak trees as their main component. As a result of differing land-uses, the structure of vegetation found within dehesas varies between: (i) oak trees and intercropped cereals (cropped), (ii) oak trees and native grass vegetation (grazed), and (iii) oak trees with abundant understorey shrubs (encroached). The aim of this study is to investigate whether land-use influences the water dynamics of dehesas by measuring available soil water content (AWC) in the upper 250 cm of the soil at different distances from tree trunks (maximum 30 m) at four Quercus ilex dehesas in Central–Western Spain. The technique used was Time Domain Reflectometry and the study was undertaken between May of 2002 and December of 2005. Leaf water potential (Ψ) was also measured on trees at one site by mean of a pressure chamber. Within the upper meter of the soil, it appears that trees, grasses and shrubs extracted soil water resources in a similar way from both beneath and beyond the tree canopy. However, encroached plots in general showed lower average AWC values than cropped or grazed plots (3.7, 5.6, and 6.2% in encroached, cropped and grazed, respectively). Cereal crops do not compete more strongly than grasses with trees for available soil water resources. The similar Ψ values found at cropped and grazed plots supported these results. From our results, it could be hypothesized that ploughed dehesas could facilitate soil re-watering in the plots with pronounced slopes. The decrease of AWC values at encroached plots with respect to the cropped and grazed plots was found mostly beyond the tree trunk at deeper soil layers, indicating that shrubs use water partly not accessible to trees. The presence of an understory of shrubs seems to have slightly increased the water constraints on trees during the summer period (Ψd values of −0.5, −0.5, and −0.8 MPa in cropped, grazed, and encroached plots, respectively). In cropped and grazed plots, an important amount of water seems to have remained unused for trees and grasses.
Keywords: available water content; cultivation; Encroachment; fertilisation; Land-use

Effect of mediterranean forest parasite with Curculio sp. on nutritional value of acorn for Iberian pig feeding and fat characteristics. - Daza, a; López-Bote, C. J.; Tomás Barberán, F. a; Espin, J. C.; López Carrasco, C.; Olivares, A.; Rey, a I. (Meat science, 2007)
Sixteen Iberian barrows of the same age with an average initial live weight of 100.1kg were randomly distributed in two groups of eight pigs each. One group was fed healthy acorns and the other group received acorns infested of Curculio sp. The subcutaneous backfat from pigs fed healthy acorns had higher C18:1n-9, MUFA and C20:5n-3 and lower C18:0 and SFA proportions than that from the pigs fed acorns infested with Curculio. The consumption of acorns infested with Curculio sp. led to a reduction of C18:1n-9, MUFA, C18:2n-6, C18:3n-3, C22:5n-3 and PUFA proportions in neutral lipids from Longissimus dorsi muscle with respect to consumption of healthy acorns, whereas in polar lipids it produced a reduction in C18:1n-9, MUFA and C18:4n-3 proportions and an increase in C18:2n-6, C20:4n-6, n-6 and C20:5n-3 proportions and of n-6/n-3 ratio with respect to the healthy acorns consumption. The pigs fed healthy acorns had higher intramuscular fat percentage in Longissimus dorsi than pigs fed with acorns infested with Curculio (9.95 vs 7.09% SEM=0.60).
The following values have no corresponding Zotero field: accession-num: 22064301
Keywords: Curculio; fat; fatty acid; iberian pig

Effect of mediterranean forest parasite with Curculio sp. on nutritional value of acorn for Iberian pig feeding and fat characteristics. - Daza, a; López-Bote, C J; Tomás Barberán, F a; Espin, J C; López Carrasco, C; Olivares, A; Rey, a I (Meat science, 2007)
Sixteen Iberian barrows of the same age with an average initial live weight of 100.1kg were randomly distributed in two groups of eight pigs each. One group was fed healthy acorns and the other group received acorns infested of Curculio sp. The subcutaneous backfat from pigs fed healthy acorns had higher C18:1n-9, MUFA and C20:5n-3 and lower C18:0 and SFA proportions than that from the pigs fed acorns infested with Curculio. The consumption of acorns infested with Curculio sp. led to a reduction of C18:1n-9, MUFA, C18:2n-6, C18:3n-3, C22:5n-3 and PUFA proportions in neutral lipids from Longissimus dorsi muscle with respect to consumption of healthy acorns, whereas in polar lipids it produced a reduction in C18:1n-9, MUFA and C18:4n-3 proportions and an increase in C18:2n-6, C20:4n-6, n-6 and C20:5n-3 proportions and of n-6/n-3 ratio with respect to the healthy acorns consumption. The pigs fed healthy acorns had higher intramuscular fat percentage in Longissimus dorsi than pigs fed with acorns infested with Curculio (9.95 vs 7.09% SEM=0.60).
Keywords: Curculio; fat; fatty acid; iberian pig

Effect of single Quercus ilex trees upon spatial and seasonal changes in soil water content in dehesas of central western Spain - Cubera, Elena; Moreno, Gerardo; Elena, C.; Gerardo, M. (Ann. For. Sci., 2007)
The spatial and temporal evolution of soil water content () in Quercus ilex dehesas has been investigated to determine how trees modify the soil water dynamics and the nature of tree-grass interactions in terms of soil water use in these ecosystems. Soil physical parameters and were measured at different distances from the tree trunk (2-30 m) in the upper 300 cm of soil. was measured monthly by TDR during 2002-2005. Tree water potential was determined during the summers of 2004 and 2005. At deeper soil layers, mean values were higher beyond than beneath tree canopy during dry periods. depletion beyond tree canopy continued even in summer, when herbaceous plants dried up, suggesting that trees uptake water from the whole inter-tree space. Results have shown a high dependence of trees on deep water reserves throughout late spring and summer, which helps to avoid competition for water with herbaceous vegetation.
Keywords: Oak woodland; Quercus ilex; Soil water content; TDR; tree-grass interaction

Effect of single Quercus ilex trees upon spatial and seasonal changes in soil water content in dehesas of central western Spain - Cubera, Elena; Moreno, Gerardo; Elena, C; Gerardo, M (Ann. For. Sci., 2007)
The spatial and temporal evolution of soil water content () in Quercus ilex dehesas has been investigated to determine how trees modify the soil water dynamics and the nature of tree-grass interactions in terms of soil water use in these ecosystems. Soil physical parameters and were measured at different distances from the tree trunk (2-30 m) in the upper 300 cm of soil. was measured monthly by TDR during 2002-2005. Tree water potential was determined during the summers of 2004 and 2005. At deeper soil layers, mean values were higher beyond than beneath tree canopy during dry periods. depletion beyond tree canopy continued even in summer, when herbaceous plants dried up, suggesting that trees uptake water from the whole inter-tree space. Results have shown a high dependence of trees on deep water reserves throughout late spring and summer, which helps to avoid competition for water with herbaceous vegetation.
Keywords: Oak woodland; Quercus ilex; Soil water content; TDR; tree-grass interaction

Effects of herbage ingestion on the digestion site and nitrogen balance in heavy Iberian pigs fed on an acorn-based diet - Garcia-Valverde, R; Nieto, R; Lachica, M; Aguilera, J F (LIVESTOCK SCIENCE, 2007)
We conducted two experiments in heavy-weight Iberian pigs to determine: a) the effect of lysine or protein addition - the former as L-lysine-HCl, the latter by fresh cut herbage supplementation - on protein deposition when they were fed on holm-oak acorns; b) the digestibility of energy and nutrients in acorns and freshly cut, mixed herbage; and c) a possible change in the partition of digestion along the gastro-intestinal tract of the pigs fed on acorns with the inclusion of herbage. In Experiment 1, carried out in eight cannulated pigs, the daily intake of acorns reached 44.9 g DM/kg(0.75) BW and the addition of 0.58 g L-lysine/kg of whole acorns failed to alter N retention significantly (P > 0.05). We obtained high coefficients for the apparent total-tract digestibility of dry matter (ApDM(tt), 0.84) and organic matter (ApOM(tt), 0.86) and of gross energy (ApGE(tt), 0.84) in whole acorns. The corresponding ileal values were 0.71, 0.74 and 0.74. The N balance was on average - 1.08 g/day. In Experiment 2, fresh herbage containing principally legumes was offered to six cannulated Iberian pigs of 140 kg either as a single feed (13.7 g DM/kg(0.75) BW) or as a supplement to acorns (28.4 g DM/kg(0.75) BW; in this case the herbage accounted for 22% of the daily DM intake). The apparent ileal digestibilities of OM and GE for herbage accounted for 70 to 77% of the values observed at total-tract level (0.65 and 0.64 respectively). N retention reached 4.21 g/day. Average ApDM(tt), ApOM(tt) and ApGE(tt) in the herbage/whole-acorn mixture were slightly above 0.74. The intake of freshly cut herbage as complementary feed to acorns resulted in a significant transference of digesta from the small intestine to the hind gut together with a substantial decrease in ileal digestibility of nutrients and energy (P < 0.001) and a moderate decline in digestibility at throughout the whole tract (P < 0.01-P < 0.001). On the other hand, the apparent digestibility of total N increased (P < 0.001) and 31% of the N apparently digested was retained in the body of the pigs. We also observed a substantial decrease in the precaecal digestion of the DM (P < 0.01), OM (P < 0.01) and GE (P < 0.05) in acorn kernels. We concluded that the main contribution of herbage to the overall nutrient supply to the grazing Iberian pig would rely upon the provision of amino acid N and also of available minerals, both present in low quantities in acorns. (C) 2007 Elsevier B.V All rights reserved.
Keywords: acorns; digestibility; energy value; herbage; iberian pig

Effects of herbage ingestion on the digestion site and nitrogen balance in heavy Iberian pigs fed on an acorn-based diet - Garcia-Valverde, R.; Nieto, R.; Lachica, M.; Aguilera, J. F. (LIVESTOCK SCIENCE, 2007)
We conducted two experiments in heavy-weight Iberian pigs to determine: a) the effect of lysine or protein addition - the former as L-lysine-HCl, the latter by fresh cut herbage supplementation - on protein deposition when they were fed on holm-oak acorns; b) the digestibility of energy and nutrients in acorns and freshly cut, mixed herbage; and c) a possible change in the partition of digestion along the gastro-intestinal tract of the pigs fed on acorns with the inclusion of herbage. In Experiment 1, carried out in eight cannulated pigs, the daily intake of acorns reached 44.9 g DM/kg(0.75) BW and the addition of 0.58 g L-lysine/kg of whole acorns failed to alter N retention significantly (P > 0.05). We obtained high coefficients for the apparent total-tract digestibility of dry matter (ApDM(tt), 0.84) and organic matter (ApOM(tt), 0.86) and of gross energy (ApGE(tt), 0.84) in whole acorns. The corresponding ileal values were 0.71, 0.74 and 0.74. The N balance was on average - 1.08 g/day. In Experiment 2, fresh herbage containing principally legumes was offered to six cannulated Iberian pigs of 140 kg either as a single feed (13.7 g DM/kg(0.75) BW) or as a supplement to acorns (28.4 g DM/kg(0.75) BW; in this case the herbage accounted for 22% of the daily DM intake). The apparent ileal digestibilities of OM and GE for herbage accounted for 70 to 77% of the values observed at total-tract level (0.65 and 0.64 respectively). N retention reached 4.21 g/day. Average ApDM(tt), ApOM(tt) and ApGE(tt) in the herbage/whole-acorn mixture were slightly above 0.74. The intake of freshly cut herbage as complementary feed to acorns resulted in a significant transference of digesta from the small intestine to the hind gut together with a substantial decrease in ileal digestibility of nutrients and energy (P < 0.001) and a moderate decline in digestibility at throughout the whole tract (P < 0.01-P < 0.001). On the other hand, the apparent digestibility of total N increased (P < 0.001) and 31% of the N apparently digested was retained in the body of the pigs. We also observed a substantial decrease in the precaecal digestion of the DM (P < 0.01), OM (P < 0.01) and GE (P < 0.05) in acorn kernels. We concluded that the main contribution of herbage to the overall nutrient supply to the grazing Iberian pig would rely upon the provision of amino acid N and also of available minerals, both present in low quantities in acorns. (C) 2007 Elsevier B.V All rights reserved.
The following values have no corresponding Zotero field: pub-location: PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS publisher: ELSEVIER SCIENCE BV
Keywords: acorns; digestibility; energy value; herbage; iberian pig

Effects of Stratification and Growth Regulators on Seed Germination and Seedling Growth of Quercus ilex L - Ghasemi, M.; Khosh-Khui, M. (Journal of Plant Sciences, 2007)
In order to study the nature of seed dormancy of Quercus ilex L., in two separate experiments pericarp-removed seeds were stratified for 0, 1, 2, 3 and 4 months or treated with concentrations of benzyl adenine (BA) (50, 100, 200 and 400 mg L-1), gibberellic acid (GA3) (100, 200, 400 and 800 mg L-1) or combinations of them (50 mg L-1 BA+100 mg L-1 GA3 or 200 mg L-1 BA+400 mg L-1 GA3 or 400 mg L-1 BA+800 mg L-1 GA3). Stratification (1 to 2 months in 5°C) increased seed emergence up to 66.66%. Application of 200 mg L-1 BA+400 mg L-1 GA3 resulted in highest emergence rates. In average, the highest leaf number, fresh and dry weights (5.23, 0.746 g and 0.296 g, respectively) were obtained when 200 mg L-1 BA alone was used. Using of 800 mg L-1 GA3 resulted in longest shoot (6.82 cm) after two months.
Keywords: Emergence; growth regulators; Quercus ilex; seed dormancy

Effects of Stratification and Growth Regulators on Seed Germination and Seedling Growth of Quercus ilex L - Ghasemi, M; Khosh-Khui, M (Journal of Plant Sciences, 2007)
In order to study the nature of seed dormancy of Quercus ilex L., in two separate experiments pericarp-removed seeds were stratified for 0, 1, 2, 3 and 4 months or treated with concentrations of benzyl adenine (BA) (50, 100, 200 and 400 mg L-1), gibberellic acid (GA3) (100, 200, 400 and 800 mg L-1) or combinations of them (50 mg L-1 BA+100 mg L-1 GA3 or 200 mg L-1 BA+400 mg L-1 GA3 or 400 mg L-1 BA+800 mg L-1 GA3). Stratification (1 to 2 months in 5°C) increased seed emergence up to 66.66%. Application of 200 mg L-1 BA+400 mg L-1 GA3 resulted in highest emergence rates. In average, the highest leaf number, fresh and dry weights (5.23, 0.746 g and 0.296 g, respectively) were obtained when 200 mg L-1 BA alone was used. Using of 800 mg L-1 GA3 resulted in longest shoot (6.82 cm) after two months.
Keywords: Emergence; growth regulators; Quercus ilex; seed dormancy

Effects of trees and understorey management on soil fertility and nutritional status of holm oaks in Spanish dehesas - Moreno, Gerardo; Obrador, José Jesús (Nutrient Cycling in Agroecosystems, 2007)
A dehesa is a multipurpose agroforestry system with scattered oaks. This study focuses on the inﬂuence of trees on soil chemical fertility and on the consequences of dehesa land use for soil fertility and nutritional status of trees. To achieve that we have studied the content of several nutrients in soils and tree leaves in four Spanish dehesas, considering three types of land use: scattered holm oak with an understorey of either native grasses (G), shrubs (E) or crop (C: either fertilized or unfertilized). We randomly selected six oaks per farm and land use for soil and tree leaf sampling. Soil samples were taken at ﬁve distances from each tree trunk (2, 5, 10, 15, and 20 m) at a depth of 0–30 cm. SOM, CEC, total and mineral-N, available-P, and exchangeable Ca, Mg and K were analysed. Foliar samples were collected from every tree in two consecutive years (2002 and 2003) at leaf maturity. The total content of N, P, K, Ca, and Mg was determined. Soils of C plots showed signiﬁcantly higher contents for most of the nutrients studied than G ones. Cropping also affected trees positively, with higher foliar contents of N and K in C plots than in G ones. Foliar content did not decrease for any nutrient, and tree-crop interaction is interpreted as a mechanism of complementarity in terms of nutrient use. Shrub encroachment led to a higher content of organic-N and exchangeable cations in soils, but to a decrease in mineral N and available-P. The tree foliar contents of N, Mg, and Ca were lower in E plots than in G plots, probably as a consequence of the tree-shrub competition for those nutrients. By contrast, P content of tree leaves increased signiﬁcantly in E plots compared to G plots.
Keywords: Encroachment; Intercrop; Nutrient pump; open woodland; Tree-understorey interaction

Environmental heterogeneity, bird-mediated directed dispersal, and oak woodland dynamics in Mediterranean Spain - Purves, Drew W.; Zavala, Miguel A.; Ogle, Kiona; Prieto, Fernando; Benayas, Jose M. Rey (ECOLOGICAL MONOGRAPHS, 2007)
Vegetation dynamics in complex landscapes depend on interactions among environmental heterogeneity, disturbance, habitat fragmentation, and seed dispersal processes. We explore how these features combine to affect the regional abundances and distributions of three Quercus (oak) species in central Spain: Q. faginea (deciduous tree), Q. ilex (evergreen tree), and Q. coccifera (evergreen shrub). We develop and parameterize a stochastic patch occupancy model (SPOM) that, unlike previous SPOMs, includes environmentally driven variation in disturbance and establishment. Dispersal in the model is directed toward local (nearby) suitable habitat patches, following the observed seed-caching behavior of the European Jay. Model parameters were estimated using Bayesian methods and survey data from 12 047 plots. Model simulations were conducted to explore the importance of different dispersal modes (local directed, global directed, local random, global random). The SPOM with local directed dispersal gave a much better fit to the data and reproduced observed regional abundance, abundance-environment correlations, and spatial autocorrelation in abundance for all three species. Model simulations suggest that jay-mediated directed dispersal increases regional abundance and alters species-environment correlations. Local dispersal is estimated to reduce regional abundances, amplify species-environment correlations, and amplify spatial autocorrelation. Parameter estimates and model simulations reveal important species-specific differences in sensitivity to environmental perturbations and dispersal mode. The dominant species Q. ilex is estimated to be highly fecund, but on the edge of its climatic tolerance. Therefore Q. ilex gains little from directed dispersal, suffers little from local dispersal, and is relatively insensitive to changes in habitat cover or disturbance rate; but Q. ilex is highly sensitive to altered drought length. In contrast, the rarest species, Q. coccifera, is well adapted to the climate and soils but has low fecundity; thus, it is highly sensitive to changes in dispersal, habitat cover, and disturbance but insensitive to altered drought length. Finally, Q. faginea is estimated to be both at the edge of its climatic tolerance and to have low fecundity, making it sensitive to all perturbations. Apparently, co-occurring species can exhibit very different interactions among dispersal, environmental characteristics, and physiological tolerances, calling for increased attention to species-specific dynamics in determining regional vegetation responses to anthropogenic perturbations.
The following values have no corresponding Zotero field: pub-location: 1707 H ST NW, STE 400, WASHINGTON, DC 20006-3915 USA publisher: ECOLOGICAL SOC AMER
Keywords: biogeography; climate change; climate envelope; corvids; dispersal limitation; Garrulus; Holm oak; Iberian peninsular; incidence function; patch model; species migration; zoochory

Environmental heterogeneity, bird-mediated directed dispersal, and oak woodland dynamics in Mediterranean Spain - Purves, Drew W; Zavala, MIGUEL a; Ogle, Kiona; Prieto, Fernando; Benayas, Jose M Rey (ECOLOGICAL MONOGRAPHS, 2007)
Vegetation dynamics in complex landscapes depend on interactions among environmental heterogeneity, disturbance, habitat fragmentation, and seed dispersal processes. We explore how these features combine to affect the regional abundances and distributions of three Quercus (oak) species in central Spain: Q. faginea (deciduous tree), Q. ilex (evergreen tree), and Q. coccifera (evergreen shrub). We develop and parameterize a stochastic patch occupancy model (SPOM) that, unlike previous SPOMs, includes environmentally driven variation in disturbance and establishment. Dispersal in the model is directed toward local (nearby) suitable habitat patches, following the observed seed-caching behavior of the European Jay. Model parameters were estimated using Bayesian methods and survey data from 12 047 plots. Model simulations were conducted to explore the importance of different dispersal modes (local directed, global directed, local random, global random). The SPOM with local directed dispersal gave a much better fit to the data and reproduced observed regional abundance, abundance-environment correlations, and spatial autocorrelation in abundance for all three species. Model simulations suggest that jay-mediated directed dispersal increases regional abundance and alters species-environment correlations. Local dispersal is estimated to reduce regional abundances, amplify species-environment correlations, and amplify spatial autocorrelation. Parameter estimates and model simulations reveal important species-specific differences in sensitivity to environmental perturbations and dispersal mode. The dominant species Q. ilex is estimated to be highly fecund, but on the edge of its climatic tolerance. Therefore Q. ilex gains little from directed dispersal, suffers little from local dispersal, and is relatively insensitive to changes in habitat cover or disturbance rate; but Q. ilex is highly sensitive to altered drought length. In contrast, the rarest species, Q. coccifera, is well adapted to the climate and soils but has low fecundity; thus, it is highly sensitive to changes in dispersal, habitat cover, and disturbance but insensitive to altered drought length. Finally, Q. faginea is estimated to be both at the edge of its climatic tolerance and to have low fecundity, making it sensitive to all perturbations. Apparently, co-occurring species can exhibit very different interactions among dispersal, environmental characteristics, and physiological tolerances, calling for increased attention to species-specific dynamics in determining regional vegetation responses to anthropogenic perturbations.
Keywords: biogeography; climate change; climate envelope; corvids; dispersal limitation; Garrulus; Holm oak; Iberian peninsular; incidence function; patch model; species migration; zoochory

Environmental induced variations in leaf dark respiration and net photosynthesis of Quercus ilex L. - Gratani, L; Varone, L; Bonito, A (Photosynthetica, 2007)
The relationships between dark respiration rate (RD) and net photosynthetic rate (PN) in Quercus ilex L. shrubs growing at the Botanical Garden in Rome were analysed. Correlation analysis of the data sets collected in the year 2006 confirmed the dependence among the considered leaf traits, in particular, RD was significantly (p<0.05) correlated with PN (r = 0.40). RD and PN increased from March to May [1.40±0.10 and 10.1±1.8 μmol(CO2) m –2 s –1 mean values of the period, respectively], when air temperature was in the range 14.8–25.2 °C, underlining the highest metabolic activity in the period of the maximum vegetative activity that favoured biomass accumulation. On the contrary, the highest RD [1.60±0.02 μmol(CO2) m –2 s –1 ], associated to the lowest PN rates (44 % of the maximum) and carbon use efficiency (CUE) in July underlined the mobilization of stored material during drought stress by a higher air temperature (32.7 °C).
Keywords: carbon use efficiency; Leaf temperature; seasonal course

Estimation of white grub damage (Coleoptera : Scarabaeoidea) in cork oak (Quercus suber L.) regeneration parcels of the Mamora forest (Morocco) and search for biological control using sex pheromones. - Ghaioule, Driss; Lumaret, Jean-Pierre; Rochat, Didier; Maatouf, Noureddine; Niogret, Jerome (ANNALES DE LA SOCIETE ENTOMOLOGIQUE DE FRANCE, 2007)
During the last decades, the cork oak restoration in the Mamora forest (Morocco) was faced with massive root attacks of seedling plantations by white grubs (Coleoptera: Scarabaeoidea). In most cases, the success of the restoration reached only 12%. Sphodroxia maroccana Ley (Melolonthidae) can be considered as the main pest in the restoration parcels. Some traits of the biology of this species are specified, despite shortcomings in the knowledge of the precise period of male emergence with regard to females, the longevity of adults and the sex-ratio. Summer drought, a season without white grub activity, is another main cause of mortality of young plantations. During the first year after plantation in experimental parcels, the cumulated mortality due to these two factors ranged between 41 and 68% according to the blocks in the parcels. The mortality associated with S. maroccana larvae ranged between 24 and 43%, with a distribution of infestation depending on density of young plants. Solid phase micro-extraction used to sample volatiles from the headspace of S. maroccana females allowed to isolate resorcinol (1,3-benzenediol) as presumed female sex pheromone. The role of this molecule has to be demonstrated.
Keywords: 1-3-benzenediol; biological control; Cork oak; damage; Morocco; pheromone; resorcinol; Restoration; Scarabaeoidea; white grubs

Estimation of white grub damage (Coleoptera : Scarabaeoidea) in cork oak (Quercus suber L.) regeneration parcels of the Mamora forest (Morocco) and search for biological control using sex pheromones. - Ghaioule, Driss; Lumaret, Jean-Pierre; Rochat, Didier; Maatouf, Noureddine; Niogret, Jerome (ANNALES DE LA SOCIETE ENTOMOLOGIQUE DE FRANCE, 2007)
During the last decades, the cork oak restoration in the Mamora forest (Morocco) was faced with massive root attacks of seedling plantations by white grubs (Coleoptera: Scarabaeoidea). In most cases, the success of the restoration reached only 12%. Sphodroxia maroccana Ley (Melolonthidae) can be considered as the main pest in the restoration parcels. Some traits of the biology of this species are specified, despite shortcomings in the knowledge of the precise period of male emergence with regard to females, the longevity of adults and the sex-ratio. Summer drought, a season without white grub activity, is another main cause of mortality of young plantations. During the first year after plantation in experimental parcels, the cumulated mortality due to these two factors ranged between 41 and 68% according to the blocks in the parcels. The mortality associated with S. maroccana larvae ranged between 24 and 43%, with a distribution of infestation depending on density of young plants. Solid phase micro-extraction used to sample volatiles from the headspace of S. maroccana females allowed to isolate resorcinol (1,3-benzenediol) as presumed female sex pheromone. The role of this molecule has to be demonstrated.
The following values have no corresponding Zotero field: pub-location: 45 RUE BUFFON, 75005 PARIS, FRANCE publisher: SOC ENTOMOLOGIQUE FRANCE
Keywords: 1-3-benzenediol; biological control; Cork oak; damage; Morocco; pheromone; resorcinol; Restoration; Scarabaeoidea; white grubs

Ethnobotany of Montseny biosphere reserve (Catalonia, Iberian Peninsula): plants used in veterinary medicine. - Bonet, M Angels; Vallès, Joan (Journal of ethnopharmacology, 2007)
The present paper deals with plants used in veterinary medicine in Montseny. An ethnobotanical survey was carried out in the Montseny massif, which is situated in north-east Catalonia (Iberian Peninsula), covers 826 km(2) and has a population of 80,000. The information was obtained through 120 ethnobotanical interviews to 180 informants. Out of 584 species reported, 351 are claimed to be used in the health field (human and veterinary medicine), 280 in human and animal food and 236 have another kind of popular use. Medicinal species represent around 16.5% of Montseny's vascular flora. In a previous paper we addressed plant use in human medicine, and the present paper deals with veterinarian uses. As a reflection of the importance of rural life in the region, at least until recent times, a substantial number of medicinal plants (89 species, representing 6% of the flora of the territory and 6.4% of all medicinal use-reports in the region) is used in veterinary medicine. These remedies are mostly for cows, calves, sheep, pigs and horses, and secondarily, to poultry, rabbits and dogs. The main ailments treated are postnatal problems, intestinal troubles, wounds and dermatological problems. In many cases, the use of these remedies in veterinary medicine is fully consistent with their use in human medicine.
Keywords: Catalonia; Ethnobotany; Ethnoveterinary; Medicinal plants; montseny; Traditional knowledge

Ethnobotany of Montseny biosphere reserve (Catalonia, Iberian Peninsula): plants used in veterinary medicine. - Bonet, M. Angels; Vallès, Joan (Journal of ethnopharmacology, 2007)
The present paper deals with plants used in veterinary medicine in Montseny. An ethnobotanical survey was carried out in the Montseny massif, which is situated in north-east Catalonia (Iberian Peninsula), covers 826 km(2) and has a population of 80,000. The information was obtained through 120 ethnobotanical interviews to 180 informants. Out of 584 species reported, 351 are claimed to be used in the health field (human and veterinary medicine), 280 in human and animal food and 236 have another kind of popular use. Medicinal species represent around 16.5% of Montseny's vascular flora. In a previous paper we addressed plant use in human medicine, and the present paper deals with veterinarian uses. As a reflection of the importance of rural life in the region, at least until recent times, a substantial number of medicinal plants (89 species, representing 6% of the flora of the territory and 6.4% of all medicinal use-reports in the region) is used in veterinary medicine. These remedies are mostly for cows, calves, sheep, pigs and horses, and secondarily, to poultry, rabbits and dogs. The main ailments treated are postnatal problems, intestinal troubles, wounds and dermatological problems. In many cases, the use of these remedies in veterinary medicine is fully consistent with their use in human medicine.
The following values have no corresponding Zotero field: accession-num: 17059874
Keywords: Catalonia; Ethnobotany; Ethnoveterinary; Medicinal plants; montseny; Traditional knowledge

Evaluation of the energy value of plant species consumed by the Barbary Deer (Cervus elaphus barbarus, Bennet 1833) in the area of El Ayoune (El Kala National Park, Algeria) - Arbouche, Halima Saadia; Arbouche, Fodil (REVUE D ECOLOGIE-LA TERRE ET LA VIE, 2007)
Plant species taken for food by the Barbary Deer were determined by direct observation during one year. On the basis of their chemical composition and phenological stage, the energy value of the grazed plant species has been expressed in stag-units as suggested by Brelurut et al. (1990). Results show that the more energy-giving elements are plants from the herbaceous layer and the acorns of Cork Oak (Quercus suber). From the shrubby layer, the Strawberry-tree (Arbustus unedo) comes first with an energy value comparable to that of green grass fodder, followed by Tree Heath (Erica arborea), Lentisc (Pistacia lentiscus) and Filaria (Phillyrea augustifolia) with energy values comparable to those of grass hays. The energy values of the other shrubby plant species are comparable with those of cereal straws; they do not ensure but the needs for maintenance.
Key W: ASKey W: ASThe following values have no corresponding Zotero field: pub-location: 57 RUE CUVIER, 75005 PARIS 5, FRANCE publisher: SOC NATL PROTECTION NATURE ACCLIMATATION FRANCE
Keywords: grazed plant species; herbaceous; Quercus ilex.L; Quercus suber L.

Evaluation of the energy value of plant species consumed by the Barbary Deer (Cervus elaphus barbarus, Bennet 1833) in the area of El Ayoune (El Kala National Park, Algeria) - Arbouche, Halima Saadia; Arbouche, Fodil (REVUE D ECOLOGIE-LA TERRE ET LA VIE, 2007)
Plant species taken for food by the Barbary Deer were determined by direct observation during one year. On the basis of their chemical composition and phenological stage, the energy value of the grazed plant species has been expressed in stag-units as suggested by Brelurut et al. (1990). Results show that the more energy-giving elements are plants from the herbaceous layer and the acorns of Cork Oak (Quercus suber). From the shrubby layer, the Strawberry-tree (Arbustus unedo) comes first with an energy value comparable to that of green grass fodder, followed by Tree Heath (Erica arborea), Lentisc (Pistacia lentiscus) and Filaria (Phillyrea augustifolia) with energy values comparable to those of grass hays. The energy values of the other shrubby plant species are comparable with those of cereal straws; they do not ensure but the needs for maintenance.
Key W: AS
Keywords: grazed plant species; herbaceous; Quercus ilex.L; Quercus suber L.

Evergreen Mediterranean hardwoods as particleboard raw material - Barboutis, John a; Philippou, John L. (Building and Environment, 2007)
Wood and biomass (branches and foliage) of ﬁve Mediterranean evergreen hardwood species (Quercus coccifera, Quercus ilex, Arbutus unedo, Phillyrea latifolia, Erica arborea) growing in Greece were investigated as particleboard raw material. The average diameter of the stems varied between the species from 4.1 cm (Erica arborea) to 7.5 cm (Quercus ilex) and the bark to wood ratio of the stems varied between the species from 7.8% (Quercus ilex) to 15.9% (Erica arborea). Bulk density of particleboard furnishes produced by processing the above materials through a chipper and a ring ﬂaker varied between the species from 143.6 to 162.5 kg/m 3 . Common industrial furnish reached in the used lab conditions a bulk density of 143 kg/m 3 . Particle size and their distribution also varied between the hardwood species. One-layer laboratory particleboards made with the above materials at densities of 650, 700 and 750 kg/m 3 had considerable lower mechanical properties but better dimensional stability than boards made with common industrial furnish. All properties were affected by wood species and board density. Internal bond of all boards was higher than the value required by EN 319/1993 but adequate bending strength at moderate densities (0.70 kg/m 3 ) was achieved only in boards made with Arbutus unedo and Quercus ilex. Boards made with branches and foliage had very low mechanical properties.
Keywords: biomass; mediterranean evergreen hardwoods; particleboard

Evergreen Mediterranean hardwoods as particleboard raw material - Barboutis, John a.; Philippou, John L (Building and Environment, 2007)
Wood and biomass (branches and foliage) of ﬁve Mediterranean evergreen hardwood species (Quercus coccifera, Quercus ilex, Arbutus unedo, Phillyrea latifolia, Erica arborea) growing in Greece were investigated as particleboard raw material. The average diameter of the stems varied between the species from 4.1 cm (Erica arborea) to 7.5 cm (Quercus ilex) and the bark to wood ratio of the stems varied between the species from 7.8% (Quercus ilex) to 15.9% (Erica arborea). Bulk density of particleboard furnishes produced by processing the above materials through a chipper and a ring ﬂaker varied between the species from 143.6 to 162.5 kg/m 3 . Common industrial furnish reached in the used lab conditions a bulk density of 143 kg/m 3 . Particle size and their distribution also varied between the hardwood species. One-layer laboratory particleboards made with the above materials at densities of 650, 700 and 750 kg/m 3 had considerable lower mechanical properties but better dimensional stability than boards made with common industrial furnish. All properties were affected by wood species and board density. Internal bond of all boards was higher than the value required by EN 319/1993 but adequate bending strength at moderate densities (0.70 kg/m 3 ) was achieved only in boards made with Arbutus unedo and Quercus ilex. Boards made with branches and foliage had very low mechanical properties.
Keywords: biomass; mediterranean evergreen hardwoods; particleboard

Evidence of selective burning in Sardinia (Italy): which land-cover classes do wildfires prefer? - Bajocco, Sofia; Ricotta, Carlo (Landscape Ecology, 2007)
The objective of this paper is to identify land-cover types where ﬁre incidence is higher (preferred) or lower (avoided) than expected from a random null model. Fire selectivity may be characterized by the number of ﬁres expected in a given land-cover class and by the mean surface area each ﬁre will burn. These two components of ﬁre pattern are usually independent of each other. For instance, ﬁre number is usually connected with socioeconomic causes whereas ﬁre size is largely controlled by fuel continuity. Therefore, on the basis of available ﬁre history data for Sardinia (Italy) for the period 2000– 2004 we analyzed ﬁre selectivity of given land-cover classes keeping both variables separate from each other. The results obtained from analysis of 13,377 ﬁres show that for most land-cover classes ﬁre behaves selectively, with marked preference (or avoidance) in terms of both ﬁre number and ﬁre size. Fire number is higher than expected by chance alone in urban and agricultural areas. In contrast, in forests, grasslands, and shrublands, ﬁre number is lower than expected. In grasslands and shrublands mean ﬁre size is signiﬁcantly larger than expected from a random null model whereas in urban areas, permanent crops, and heterogeneous agricultural areas there is significant resistance to ﬁre spread. Finally, as concerns mean ﬁre size, in our study area forests and arable land burn in proportion to their availability without any signiﬁcant tendency toward ﬁre preference or avoidance. The results obtained in this study contribute to ﬁre risk assessment on the landscape scale, indicating that risk of wildﬁre is closely related to land cover.
Keywords: analysis á; Fire number; fire number á fire; Fire selectivity; Fuel fragmentation; fuel fragmentation á landscape; Landscape analysis; mean fire size á; Mean ﬁre size; Permutation methods; selectivity á