Direct and indirect impacts of fire on isoprenoid emissions from Mediterranean vegetation - Alessio, G A; Lillis, M De; Fanelli, M (Functional Ecology, 2004)
1. Fire is often associated with episodes of air pollution, possibly involving the release of biogenic isoprenoids (isoprene and monoterpenes). The direct and indirect impacts of ﬁre on isoprenoid emission by plants of the Mediterranean vegetation were studied. Leaves of Arbutus unedo, Phillyrea latifolia, Cistus incanus, Cistus mospeliensis, Pistacia lentiscus, Quercus ilex, Quercus suber, Quercus pubescens, Myrtus communis and Pinus halepensis were exposed to direct ﬁre or to the ﬁre-consequent wave of elevated temperature. 2. Half the tested plant species did not emit isoprenoids and the treatments did not induce isoprenoid emission. In contrast, isoprene was emitted by intact leaves of Q. pubescens and M. communis, while monoterpenes were emitted by intact leaves of Q. ilex, Q. suber and P. halepensis. 3. The two treatments rapidly reduced isoprene emission by isoprene-emitting species and monoterpene emission by Quercus spp. This inhibition was associated with photosynthetic inhibition, and recovery was seen in Quercus spp. within days of treatment. Recovery was also associated with the recovery of photosynthesis, suggesting that emitted isoprenoids continue to be formed predominantly from photosynthetic intermediates after a ﬁre episode. 4. In Q. pubescens leaves, however, recovery from the elevated-temperature treatment caused a sustained increase of isoprene emission which was not mirrored by a similar increase in photosynthesis. Whether this represents the induction of alternative metabolic pathways or an increase of the ﬂux of photosynthetic carbon in the isoprene pathway is not known. Isoprene-emitting species in areas surrounding ﬁre may emit a substantially larger hydrocarbon ﬂux for several days after ﬁre. 5. The elevated-temperature treatment induced the emission of α-pinene from Myrtus leaves, and the ﬁre treatment stimulated the emission of several monoterpenes from Pinus needles. The emission began to decrease within minutes in Myrtus, while it increased within the ﬁrst 100 min in Pinus, where it was detectable the day after the event although the ﬂux was smaller than in prestressed needles. 6. Exposure to ﬁre and to the associated elevated temperature may induce bursts of monoterpenes from plants that regularly do not emit these compounds and temporarily increase the load of monoterpenes in the atmosphere by pine species. These emissions may contribute to photochemical reactions involved in smog and ozone formation
Keywords: isoprene; Mediterranean plant species; Monoterpenes; Ozone; photosynthesis; Stomatal conductance; ﬁre ecology

Direct and indirect impacts of fire on isoprenoid emissions from Mediterranean vegetation - Alessio, G. A.; Lillis, M. De; Fanelli, M. (Functional Ecology, 2004)
1. Fire is often associated with episodes of air pollution, possibly involving the release of biogenic isoprenoids (isoprene and monoterpenes). The direct and indirect impacts of ﬁre on isoprenoid emission by plants of the Mediterranean vegetation were studied. Leaves of Arbutus unedo, Phillyrea latifolia, Cistus incanus, Cistus mospeliensis, Pistacia lentiscus, Quercus ilex, Quercus suber, Quercus pubescens, Myrtus communis and Pinus halepensis were exposed to direct ﬁre or to the ﬁre-consequent wave of elevated temperature. 2. Half the tested plant species did not emit isoprenoids and the treatments did not induce isoprenoid emission. In contrast, isoprene was emitted by intact leaves of Q. pubescens and M. communis, while monoterpenes were emitted by intact leaves of Q. ilex, Q. suber and P. halepensis. 3. The two treatments rapidly reduced isoprene emission by isoprene-emitting species and monoterpene emission by Quercus spp. This inhibition was associated with photosynthetic inhibition, and recovery was seen in Quercus spp. within days of treatment. Recovery was also associated with the recovery of photosynthesis, suggesting that emitted isoprenoids continue to be formed predominantly from photosynthetic intermediates after a ﬁre episode. 4. In Q. pubescens leaves, however, recovery from the elevated-temperature treatment caused a sustained increase of isoprene emission which was not mirrored by a similar increase in photosynthesis. Whether this represents the induction of alternative metabolic pathways or an increase of the ﬂux of photosynthetic carbon in the isoprene pathway is not known. Isoprene-emitting species in areas surrounding ﬁre may emit a substantially larger hydrocarbon ﬂux for several days after ﬁre. 5. The elevated-temperature treatment induced the emission of α-pinene from Myrtus leaves, and the ﬁre treatment stimulated the emission of several monoterpenes from Pinus needles. The emission began to decrease within minutes in Myrtus, while it increased within the ﬁrst 100 min in Pinus, where it was detectable the day after the event although the ﬂux was smaller than in prestressed needles. 6. Exposure to ﬁre and to the associated elevated temperature may induce bursts of monoterpenes from plants that regularly do not emit these compounds and temporarily increase the load of monoterpenes in the atmosphere by pine species. These emissions may contribute to photochemical reactions involved in smog and ozone formation
Keywords: isoprene; Mediterranean plant species; Monoterpenes; Ozone; photosynthesis; Stomatal conductance; ﬁre ecology

Distribution , Ecology and Population Structure of Euphorbia monchiquensis , an Endemism in Southern Portugal - Fox, Xenia; Deil, Ulrich (Silva Lusitana, 2004)
Euphorbia monchiquensis is, within the widespread and euryoecious E. paniculata- complex, an acidophilous subspecies, endemic in Southern Portugal. To evaluate the vulnerability of this taxon vis-a-vis disturbance and landuse changes, we studied the actual distribution, the population size, the ecological requirements and the coenological value of this taxon in the Serra de Monchique, a mountainous region in the Algarve Hinterland. Data sampling was between April and July 2001. The quite constant branching system of this half shrubby spurge allows to determine the age of the indivuduals from the plant architecture and therefore to study the demographic structure in a non-destructive way. 1618 individuals, clustered in 46 populations, have been registered in the Serra. 88% were in flower. Euphorbia monchiquensis is rare relative to its overall distribution. It shows a bimodal altitudinal and coenological pattern. The majority of the populations are concentrated in the most humid mid altitudes and on the luv-ward northwestern side of the Serra. A few populations occur in the dry lowlands, linked to riverine shrublets. The plant depends on a good water supply but does not need shadowing. Within its limited bioclimatic niche, the spurge has a certain capacity of recolonisation and is not extremely sensitive to disturbance. Humid forests of the Euphorbio monchiquensis-Quercetum canariensis are just one of the preferred sociological situations. The coenological spectrum includes pure cork oak forests, Castanea sativa coppices, Eucalyptus-afforestations, mantle communities (Lonicero-Rubetum, Rubo- Nerietum), Origanion virentis fringes, abandoned meadows and roadside verges. It was in this kind of secondary habitats with intermittent disturbance, that most of the juvenile plants could be stated. Only very few plantlings were found. Most of the recorded populations are well balanced in their medium age classes, others are overaged. A correlation between habitat qualities, the reproductive effort and the regeneration efficiency could not be found. Four inflorescence- -morphotypes can be distinguished. The inflorescence architecture becomes more complex with increasing age. Euphorbia monchiquensis is not an extremely endangered, but a vulnerable species. It can be threatened by the process of Eucalyptus afforestation and by the spontaneous spread of Acacia dealbata. To give a reliable answer to the extinction risk, further aspects of its life cycle, seed bank characteristics, and reproductive behaviour have to be studied.
Keywords: age-states; conservation biology; landuse; plant architecture; reproduction; serra de monchique

Distribution , Ecology and Population Structure of Euphorbia monchiquensis , an Endemism in Southern Portugal - Fox, Xenia; Deil, Ulrich (Silva Lusitana, 2004)
Euphorbia monchiquensis is, within the widespread and euryoecious E. paniculata- complex, an acidophilous subspecies, endemic in Southern Portugal. To evaluate the vulnerability of this taxon vis-a-vis disturbance and landuse changes, we studied the actual distribution, the population size, the ecological requirements and the coenological value of this taxon in the Serra de Monchique, a mountainous region in the Algarve Hinterland. Data sampling was between April and July 2001. The quite constant branching system of this half shrubby spurge allows to determine the age of the indivuduals from the plant architecture and therefore to study the demographic structure in a non-destructive way. 1618 individuals, clustered in 46 populations, have been registered in the Serra. 88% were in flower. Euphorbia monchiquensis is rare relative to its overall distribution. It shows a bimodal altitudinal and coenological pattern. The majority of the populations are concentrated in the most humid mid altitudes and on the luv-ward northwestern side of the Serra. A few populations occur in the dry lowlands, linked to riverine shrublets. The plant depends on a good water supply but does not need shadowing. Within its limited bioclimatic niche, the spurge has a certain capacity of recolonisation and is not extremely sensitive to disturbance. Humid forests of the Euphorbio monchiquensis-Quercetum canariensis are just one of the preferred sociological situations. The coenological spectrum includes pure cork oak forests, Castanea sativa coppices, Eucalyptus-afforestations, mantle communities (Lonicero-Rubetum, Rubo- Nerietum), Origanion virentis fringes, abandoned meadows and roadside verges. It was in this kind of secondary habitats with intermittent disturbance, that most of the juvenile plants could be stated. Only very few plantlings were found. Most of the recorded populations are well balanced in their medium age classes, others are overaged. A correlation between habitat qualities, the reproductive effort and the regeneration efficiency could not be found. Four inflorescence- -morphotypes can be distinguished. The inflorescence architecture becomes more complex with increasing age. Euphorbia monchiquensis is not an extremely endangered, but a vulnerable species. It can be threatened by the process of Eucalyptus afforestation and by the spontaneous spread of Acacia dealbata. To give a reliable answer to the extinction risk, further aspects of its life cycle, seed bank characteristics, and reproductive behaviour have to be studied.
Keywords: age-states; conservation biology; landuse; plant architecture; reproduction; serra de monchique

Diversity and fruiting patterns of ectomycorrhizal and saprobic fungi in an old-growth Mediterranean forest dominated by Quercus ilex L. - Richard, F.; Moreau, P.-A.; Selosse, M.-A.; Gardes, M. (Canadian Journal of Botany, 2004)
We collected and mapped epigeous fruitbodies of both ectomycorrhizal (ECM) and saprobic fungi in an oldgrowth Quercus ilex L. Mediterranean forest within a permanent transect of 6400 m2 over three consecutive fruiting seasons. Out of 5382 fruitbodies, a total of 234 species were found, including 166 and 68 ECM and saprobic taxa, respectively. Both communities were mainly composed of rare species. Two genera, Russula and Cortinarius, accounted for 34.4% of ECM fruitbodies and 50% of species diversity. The three most abundant ECM species were Laccaria laccata (Scop.: Fr.) Berk. & Broome, Inocybe tigrina R. Heim, and Lactarius chrysorrheus Fr. The fruiting ECM community encompassed a few Mediterranean species and numerous broad host range temperate species. We also analysed the fruiting patterns in relation to forest structure, host composition, and natural canopy gaps. The results showed (i) a significant correlation of species richness to tree density, (ii) a richness decrease as the number of vegetation layers increases, and (iii) a preferential fruiting of some species near Q. ilex or Arbutus unedo L. Another noteworthy feature was that richness and production were greatly enhanced in canopy gaps. Selective fruiting was also observed among species. These results highlight the importance of forest structure and large woody debris for fungal conservation.
doi: 10.1139/b04-128doi: 10.1139/b04-128The following values have no corresponding Zotero field: publisher: NRC Research Press
Keywords: canopy gaps; ECM community; fungal conservation; Holm oak; macromycete fruiting patterns; saprophytic fungi

Diversity and fruiting patterns of ectomycorrhizal and saprobic fungi in an old-growth Mediterranean forest dominated by Quercus ilex L. - Richard, F; Moreau, P -A; Selosse, M -A; Gardes, M (Canadian Journal of Botany, 2004)
We collected and mapped epigeous fruitbodies of both ectomycorrhizal (ECM) and saprobic fungi in an oldgrowth Quercus ilex L. Mediterranean forest within a permanent transect of 6400 m2 over three consecutive fruiting seasons. Out of 5382 fruitbodies, a total of 234 species were found, including 166 and 68 ECM and saprobic taxa, respectively. Both communities were mainly composed of rare species. Two genera, Russula and Cortinarius, accounted for 34.4% of ECM fruitbodies and 50% of species diversity. The three most abundant ECM species were Laccaria laccata (Scop.: Fr.) Berk. & Broome, Inocybe tigrina R. Heim, and Lactarius chrysorrheus Fr. The fruiting ECM community encompassed a few Mediterranean species and numerous broad host range temperate species. We also analysed the fruiting patterns in relation to forest structure, host composition, and natural canopy gaps. The results showed (i) a significant correlation of species richness to tree density, (ii) a richness decrease as the number of vegetation layers increases, and (iii) a preferential fruiting of some species near Q. ilex or Arbutus unedo L. Another noteworthy feature was that richness and production were greatly enhanced in canopy gaps. Selective fruiting was also observed among species. These results highlight the importance of forest structure and large woody debris for fungal conservation.
doi: 10.1139/b04-128
Keywords: canopy gaps; ECM community; fungal conservation; Holm oak; macromycete fruiting patterns; saprophytic fungi

Do different habitat preference survey methods produce the same conservation recommendations for lesser kestrels? - Franco, a. M a.; Catry, I; Sutherland, W J; Palmeirim, J M (Animal Conservation, 2004)
The analysis of habitat selection underlies many conservation recommendations. Different researchers use different methods, therefore there is a need to examine whether the results are consistent. This study examined habitat selection by lesser kestrels, Falco naumanni, a globally threatened species, using two methods: visual sighting data from a 35-km transect and radio-telemetry of 33 birds. Habitat use and spatial ecology were studied across all of the breeding season in a pseudo-steppe area, where traditional agro-grazing systems are still present but some areas have been transformed into pine plantations. Telemetry data indicate that, in good quality habitat, lesser kestrels prefer to forage close to the colony. Furthermore, the home ranges obtained were smaller than those for lesser kestrels using intensively managed habitats or more forested areas. Habitat availability was determined within a 4-km radius of the colony and habitat preferences were determined using compositional analysis. Both methods were found to produce similar results, but telemetry provided a larger number of signiﬁcant differences between habitats. Before the chicks hatched, lesser kestrels preferred grazed fallows, ploughed ﬁelds and cereal, while after hatching cereal stubble was the preferred habitat. In steppe habitats the protection of such foraging habitats within a 3-km radius from the colonies could be a very effective conservation measure.
Keywords: habitat selection; Lesser kestrel; spatial ecology (PG)

Do different habitat preference survey methods produce the same conservation recommendations for lesser kestrels? - Franco, a M. a; Catry, I.; Sutherland, W. J.; Palmeirim, J. M. (Animal Conservation, 2004)
The analysis of habitat selection underlies many conservation recommendations. Different researchers use different methods, therefore there is a need to examine whether the results are consistent. This study examined habitat selection by lesser kestrels, Falco naumanni, a globally threatened species, using two methods: visual sighting data from a 35-km transect and radio-telemetry of 33 birds. Habitat use and spatial ecology were studied across all of the breeding season in a pseudo-steppe area, where traditional agro-grazing systems are still present but some areas have been transformed into pine plantations. Telemetry data indicate that, in good quality habitat, lesser kestrels prefer to forage close to the colony. Furthermore, the home ranges obtained were smaller than those for lesser kestrels using intensively managed habitats or more forested areas. Habitat availability was determined within a 4-km radius of the colony and habitat preferences were determined using compositional analysis. Both methods were found to produce similar results, but telemetry provided a larger number of signiﬁcant differences between habitats. Before the chicks hatched, lesser kestrels preferred grazed fallows, ploughed ﬁelds and cereal, while after hatching cereal stubble was the preferred habitat. In steppe habitats the protection of such foraging habitats within a 3-km radius from the colonies could be a very effective conservation measure.
Keywords: habitat selection; Lesser kestrel; spatial ecology (PG)

The effect of cork-stripping damage on diameter growth of Quercus suber L. - Costa, A.; Pereira, H.; Oliveira, A. (Forestry, 2004)
The Mediterranean cork oak (Quercus suber L.) agro-forestry system is oriented towards cork production, with cork being extracted from tree stem and branches as planks by cutting with an axe and stripping off. The effect of damage to the tree during cork stripping was studied in cork oaks, weakened by wounding, by following the diameter growth and its seasonality during a 9-year production cycle, and comparing them with healthy cork oaks. Tree wounding decreased diameter growth during the following cycle, e.g. 8.5 mm a−1 and 9.8 mm a−1 for weakened and healthy trees, respectively, mostly in the 2 years immediately following the cork stripping. The beginning of annual growth in spring and the occurrence of the highest increments in June–August were delayed by about 1 month in the weakened trees. The cork produced by weakened trees was reduced by 13 per cent in thickness, with average cork ring widths of 3.3 mm a−1 vs. 3.8 mm a−1 for healthy trees.
10.1093/forestry/77.1.110.1093/forestry/77.1.1
Keywords: Cork Production; stripping; wound responses (PG)

The effect of cork-stripping damage on diameter growth of Quercus suber L. - Costa, a; Pereira, H; Oliveira, A (Forestry, 2004)
The Mediterranean cork oak (Quercus suber L.) agro-forestry system is oriented towards cork production, with cork being extracted from tree stem and branches as planks by cutting with an axe and stripping off. The effect of damage to the tree during cork stripping was studied in cork oaks, weakened by wounding, by following the diameter growth and its seasonality during a 9-year production cycle, and comparing them with healthy cork oaks. Tree wounding decreased diameter growth during the following cycle, e.g. 8.5 mm a−1 and 9.8 mm a−1 for weakened and healthy trees, respectively, mostly in the 2 years immediately following the cork stripping. The beginning of annual growth in spring and the occurrence of the highest increments in June–August were delayed by about 1 month in the weakened trees. The cork produced by weakened trees was reduced by 13 per cent in thickness, with average cork ring widths of 3.3 mm a−1 vs. 3.8 mm a−1 for healthy trees.
10.1093/forestry/77.1.1
Keywords: Cork Production; stripping; wound responses (PG)

The effect of cork-stripping damage on diameter growth of Quercus suber L. - Costa, a; Pereira, H; Oliveira, A (Forestry, 2004)
The Mediterranean cork oak (Quercus suber L.) agro-forestry system is oriented towards cork production, with cork being extracted from tree stem and branches as planks by cutting with an axe and stripping off. The effect of damage to the tree during cork stripping was studied in cork oaks, weakened by wounding, by following the diameter growth and its seasonality during a 9-year production cycle, and comparing them with healthy cork oaks. Tree wounding decreased diameter growth during the following cycle, e.g. 8.5 mm a−1 and 9.8 mm a−1 for weakened and healthy trees, respectively, mostly in the 2 years immediately following the cork stripping. The beginning of annual growth in spring and the occurrence of the highest increments in June–August were delayed by about 1 month in the weakened trees. The cork produced by weakened trees was reduced by 13 per cent in thickness, with average cork ring widths of 3.3 mm a−1 vs. 3.8 mm a−1 for healthy trees.
10.1093/forestry/77.1.1
Keywords: Cork Production; stripping; wound responses (PG)

The effect of low temperatures on the photosynthetic apparatus of Quercus ilex subsp. ballota at its lower and upper altitudinal limits in the Iberian peninsula and during a single freezing-thawing cycle - Corcuera, L.; Morales, F.; Abadia, A.; GIL-PELEGRÍN, E. (Trees, 2004)
We investigated the response of the photosynthetic apparatus during an episode of extreme low winter temperature in Quercus ilex subsp. ballota (Desf.) Samp., a typical Mediterranean evergreen species in the Iberian peninsula. Both plants in a woodland located at high altitude (1,177 m. a.s.l.) and potted plants obtained from acorns of the same populations grown at low altitude (225 m. a.s.l.) were analyzed. Net CO2 assimilation rate was negative and there was a marked decrease in photosystem II (PSII) efficiency during winter in leaves of the woodland population (high altitude individuals). These processes were accompanied by increases in nonphotochemical quenching (NPQ) and in the de-epoxidated carotenoids within the xanthophyll cycle, mechanisms aimed to dissipate excess energy. In addition, these deepoxidated carotenoids were largely preserved during the night. There was no chlorophyll bleaching during the winter, which suggests that leaves were not experiencing photoinhibitory damage. In fact, the net photosynthetic rate and the PSII efficiency recovered in spring. These changes were not observed, or were much more reduced, in individuals located at lower altitude after a few frosts. When the response to rapid temperature changes (from 20°C to −5°C and from −5°C to 20°C) was studied, it was found that the maximum potential PSII efficiency was fairly stable, ranging from 0.70 to 0.75. The rest of the photosynthetic parameters measured, actual and intrinsic PSII efficiency, photochemical and NPQ, responded immediately to the changes in temperature and, also, the recovery after cold events was practically immediate.
Keywords: chlorophyll fluorescence; Holm oak; photochemical and non-photochemical quenching; photoprotection; photosystem ii efficiency

The effect of low temperatures on the photosynthetic apparatus of Quercus ilex subsp. ballota at its lower and upper altitudinal limits in the Iberian peninsula and during a single freezing-thawing cycle - Corcuera, L; Morales, F; Abadía, A; Gil-Pelegrín, E (Trees, 2004)
We investigated the response of the photosynthetic apparatus during an episode of extreme low winter temperature in Quercus ilex subsp. ballota (Desf.) Samp., a typical Mediterranean evergreen species in the Iberian peninsula. Both plants in a woodland located at high altitude (1,177 m. a.s.l.) and potted plants obtained from acorns of the same populations grown at low altitude (225 m. a.s.l.) were analyzed. Net CO2 assimilation rate was negative and there was a marked decrease in photosystem II (PSII) efficiency during winter in leaves of the woodland population (high altitude individuals). These processes were accompanied by increases in nonphotochemical quenching (NPQ) and in the de-epoxidated carotenoids within the xanthophyll cycle, mechanisms aimed to dissipate excess energy. In addition, these deepoxidated carotenoids were largely preserved during the night. There was no chlorophyll bleaching during the winter, which suggests that leaves were not experiencing photoinhibitory damage. In fact, the net photosynthetic rate and the PSII efficiency recovered in spring. These changes were not observed, or were much more reduced, in individuals located at lower altitude after a few frosts. When the response to rapid temperature changes (from 20°C to −5°C and from −5°C to 20°C) was studied, it was found that the maximum potential PSII efficiency was fairly stable, ranging from 0.70 to 0.75. The rest of the photosynthetic parameters measured, actual and intrinsic PSII efficiency, photochemical and NPQ, responded immediately to the changes in temperature and, also, the recovery after cold events was practically immediate.
Keywords: chlorophyll fluorescence; Holm oak; photochemical and non-photochemical quenching; photoprotection; photosystem ii efficiency

Effects of a nursery CO 2 enriched atmosphere on the germination and seedling morphology of two Mediterranean oaks with contrasting leaf habit - Cortés, Pilar; ESPELTA, J M; Save, Robert; Biel, C (New Forests, 2004)
The use of an enriched CO2 atmosphere in tree nurseries has been envisaged as a promising technique to increase productivity and to obtain seedlings with a higher root/shoot ratio, an essential trait to respond to water stress in Mediterranean-type ecosystems. In that framework, we have analyzed the effects of three levels of atmospheric CO2 concentration (350, 500 and 700 ppm) on the germination rate, growth and morphology of seedlings of two Mediterranean oaks used in reforestation programs: the evergreen Quercus ilex L. and the deciduous Quercus cerrioides Wilk. et Costa. CO2 enrichment increased the germination rate of Q. cerrioides (from 70 7 to 81 3%) while it decreased that of Q. ilex (from 71 10 to 41 12%). Seedlings of both species increased approximately 60% their total biomass in response to CO2 enrichment but at two different CO2 concentrations: 500 ppm for Q. cerrioides and 700 ppm for Q. ilex. This increase in seedlings biomass was entirely due to an augmentation of root biomass. Considering germination and biomass partitioning, an enriched CO2 atmosphere might not be appropriate for growing Mediterranean evergreen oaks, such as Q. ilex, since it reduces acorn germination and the only gains in root biomass occur at a high concentration (700 ppm). On the other hand, a moderate CO2 enrichment (500 ppm) appears as a promising nursery technique to stimulate the germination, growth and root/shoot ratio of deciduous oaks, such as Q. cerrioides
Keywords: Forest restoration; Mediterranean-type ecosystems; Nursery techniques; Quercus cerrioides; Quercus ilex; Wildﬁre

Effects of a nursery CO 2 enriched atmosphere on the germination and seedling morphology of two Mediterranean oaks with contrasting leaf habit - Cortés, Pilar; Espelta, J. M.; Save, Robert; Biel, C. (New Forests, 2004)
The use of an enriched CO2 atmosphere in tree nurseries has been envisaged as a promising technique to increase productivity and to obtain seedlings with a higher root/shoot ratio, an essential trait to respond to water stress in Mediterranean-type ecosystems. In that framework, we have analyzed the effects of three levels of atmospheric CO2 concentration (350, 500 and 700 ppm) on the germination rate, growth and morphology of seedlings of two Mediterranean oaks used in reforestation programs: the evergreen Quercus ilex L. and the deciduous Quercus cerrioides Wilk. et Costa. CO2 enrichment increased the germination rate of Q. cerrioides (from 70 7 to 81 3%) while it decreased that of Q. ilex (from 71 10 to 41 12%). Seedlings of both species increased approximately 60% their total biomass in response to CO2 enrichment but at two different CO2 concentrations: 500 ppm for Q. cerrioides and 700 ppm for Q. ilex. This increase in seedlings biomass was entirely due to an augmentation of root biomass. Considering germination and biomass partitioning, an enriched CO2 atmosphere might not be appropriate for growing Mediterranean evergreen oaks, such as Q. ilex, since it reduces acorn germination and the only gains in root biomass occur at a high concentration (700 ppm). On the other hand, a moderate CO2 enrichment (500 ppm) appears as a promising nursery technique to stimulate the germination, growth and root/shoot ratio of deciduous oaks, such as Q. cerrioides
Keywords: Forest restoration; Mediterranean-type ecosystems; Nursery techniques; Quercus cerrioides; Quercus ilex; Wildﬁre

Effects of a severe drought on Quercus ilex radial growth and xylem anatomy - Gil-Pelegrín, Eustaquio; Corcuera, Leyre; Camarero, Jesús Julio (Trees - Structure and Function, 2004)
We assessed the response of Quercus ilex subsp. ballota to the severe summer drought recorded in 1994 in NE Spain through the study of changes in radial growth and wood anatomy. We selected a coppice stand in the Iberian Peninsula, which is characterized by a Mediterranean climate under continental influence. We measured internode length, tree-ring width, mean and maximum vessel diameter, and vessel density for 1981– 1997. The annual predicted hydraulic conductance (Kh) was calculated following Hagen-Poisseuille’s law. We compared the tree-ring width, vessel diameter and Kh of Q. ilex subsp. ballota and co-existing ring-porous oaks (Q. faginea, Q. pyrenaica) for a dry summer (1994) and a wet summer (1997). To evaluate the drought-resistance of xylem for Q. ilex subsp. ballota (dominant under continental conditions) and Q. ilex subsp. ilex (dominant in mild areas) we determined vulnerability curves. Dimensionless indices of internode length, tree-ring width, and vessel density were compared with climatic data (monthly total precipitation and mean temperature) using correlation analyses. Internode length, tree-ring width, Kh, and mean and maximum vessel diameter declined in 1994. According to vulnerability curves, Q. ilex subsp. ballota showed a greater drought resistance than Q. ilex subsp. ilex. During the year of growth, we found a positive influence of January and June–August precipitation on the internode length, tree-ring width, and vessel density. The response of Q. ilex subsp. ballota radial-growth to summer drought was comparable to that of Q. faginea latewood. Overall, growth and wood anatomy of Q. ilex subsp. ballota showed a plastic response to drought.
Keywords: cavitation; climate; Dendroecology; vulnerability curve; Xylem

Effects of partial defoliation on carbon and nitrogen partitioning and photosynthetic carbon uptake by two-year-old cork oak (Quercus suber) saplings - Cerasoli, S; Scartazza, A; Brugnoli, E; Chaves, M M; Pereira, J S (Tree Physiology, 2004)
At the end of the growing season in late July, 20-month-old cork oak (Quercus suber L.) saplings were partially defoliated (63% of leaf area) to evaluate their ability to recover leaf area after defoliation. At 18 and 127 days after defoliation, changes in starch and nitrogen pools were determined in leaves and perennial organs, and variations in photosynthetic carbon uptake were investigated. To determine the role of stored nitrogen in regrowth after defoliation, plant nitrogen was labeled in the previous winter by enriching the nutrient solution with 15N. Plants recovered the lost leaf area in 127 days. Although there was remobilization of starch and nitrogen from leaves and perennial organs, the availability of resources for growth in the following spring was not decreased by defoliation. On the contrary, starch concentration in coarse roots was higher in defoliated saplings than in control saplings, presumably as a result of the higher net CO2 exchange rate in newly developed leaves compared with pre-existing leaves.
10.1093/treephys/24.1.83
Keywords: 15N labeling; defoliation; Nitrogen remobilization; starch

Effects of partial defoliation on carbon and nitrogen partitioning and photosynthetic carbon uptake by two-year-old cork oak (Quercus suber) saplings - Cerasoli, S.; Scartazza, A.; Brugnoli, E.; Chaves, M. M.; Pereira, J. S. (Tree Physiology, 2004)
At the end of the growing season in late July, 20-month-old cork oak (Quercus suber L.) saplings were partially defoliated (63% of leaf area) to evaluate their ability to recover leaf area after defoliation. At 18 and 127 days after defoliation, changes in starch and nitrogen pools were determined in leaves and perennial organs, and variations in photosynthetic carbon uptake were investigated. To determine the role of stored nitrogen in regrowth after defoliation, plant nitrogen was labeled in the previous winter by enriching the nutrient solution with 15N. Plants recovered the lost leaf area in 127 days. Although there was remobilization of starch and nitrogen from leaves and perennial organs, the availability of resources for growth in the following spring was not decreased by defoliation. On the contrary, starch concentration in coarse roots was higher in defoliated saplings than in control saplings, presumably as a result of the higher net CO2 exchange rate in newly developed leaves compared with pre-existing leaves.
10.1093/treephys/24.1.8310.1093/treephys/24.1.83
Keywords: 15N labeling; defoliation; Nitrogen remobilization; starch

Effects of sulphurous gases in two CO2 springs on total sulphur and thiols in acorns and oak seedlings - Grill, D; Müller, M; Tausz, M; Strnad, B; Wonisch, A; Raschi, A (Atmospheric Environment, 2004)
Quercus ilex and Quercus pubescens acorns were collected at two CO2 springs in Tuscany (Bossoleto and Viterbo, resp.). In addition to elevated CO2, these springs are a source of H2S and SO2 . Acorns from a comparable ﬁeld site distant from CO2 springs were used as controls. Acorns from CO2 springs contained signiﬁcantly higher sulphur concentrations than controls (0.67 vs. 0.47 mg g 1 dw in Q. ilex cotyledons and 1.01 vs. 0.80 in Q. pubescens) and, in Q. ilex, also more glutathione (1634 vs. 1393 nmol g 1 dw). When acorns were germinated and seedlings grown under ambient air conditions in the Botanical Garden in Graz for one year, leaves of Q. pubescens grown from CO2 spring acorns showed signiﬁcantly higher S-concentrations than leaves grown from control acorns (2.27 mg g 1 vs. 1.56 mg g 1 dw), and those of Q. ilex higher glutathione concentrations (929 vs. 462 nmol g 1 dw, CO2 spring vs. control acorns). One-year-old Q. ilex seedlings grown from CO2 spring acorns also showed elevated rates of chromosomal aberrations in root tips (a widely used test for environmental impacts), suggesting a permanent stress situation of the seedlings originating from the CO2 springs.
Keywords: cytogenetic; Glutathione; hydrogen sulphide; Stress; Sulphur dioxide

Effects of winter cold stress on photosynthesis and photochemical efficiency of PSII of the Mediterranean Cistus albidus L. and Quercus ilex L. - Oliveira, G; Penuelas, J (Plant Ecology, 2004)
This study examined the photosynthetic and growth performances of potted plants of Cistus albidus L. and Quercus ilex L. submitted either to natural Mediterranean winter conditions or to mild greenhouse conditions. Plants grown outdoors exhibited lower light and CO2 -saturated CO2 assimilation rates Asat and apparent quantum yield i than those indoors. Until mid-winter, C. albidus had higher Asat than Q. ilex, but differences disappeared after a period of severe cold. Maximal photochemical efficiency of PSII Fv/Fm measured predawn was higher in C. albidus than in Q. ilex, and decreased throughout the season in outdoor plants. Fv/Fm also decreased at light saturation Asat in both species. Fv/Fm was correlated with photosynthetic capacity and efficiency quantum yield, but the resulting regression slopes were different between the two species. At the physiological level, C. albidus seemed to cope better with cold stress than Q. ilex. However, winter stress induced reduction of leaf absorptance, increased leaf mass per area, extensive leaf damage and high plant mortality in C. albidus. This suggests that the high performance of C. albidus leaves is not likely to be maintained for long periods of cold stress, and may therefore depend on continuous leaf replacement. Quercus ilex showed a conservative behaviour, with low net assimilation rates but greater leaf and plant survival than C. albidus.
Keywords: evergreen; Fv/Fm; Mediterranean winter; photoinhibition; semi-deciduous

Establishment of co-existing Mediterranean tree species under a varying soil moisture regime - Lloret, Francisco; Penuelas, Josep; Ogaya, Romà (Journal of Vegetation Science, 2004)
We investigated the responses of two co-existing Mediterranean trees with different regeneration strategies (Phillyrea latifolia seedlings and Quercus ilex sprouts) to experimental drought below the forest canopy. We considered different recruitment stages and used leaf isotopic discrimination to estimate water use efficiency (WUE) and nitrogen availability and use. Drought decreased the emergence and survival of seedlings and sprouts. Survival and growth of older saplings were not influenced by drought. Seedling emergence of P. latifolia was higher than Q. ilex sprout production, but Q. ilex sprouts had higher survival and growth rates. These differences disappeared in the sapling stage. Carbon isotopic discrimination suggested that Q. ilex sprouts had higher WUE than P. latifolia seedlings. Drought increased WUE of recruits, particularly in Q. ilex. Water use regulation increased with ageing, particularly in P. latifolia. Q. ilex had higher δ15N values than P. latifolia; these were also higher under drier soil conditions. Current year seedlings had higher δ15N than saplings, particularly in P. latifolia, suggesting they exploit superficial soil layers. These results suggest that sprouts obtain benefit from resources stored in parent plants. At earlier stages, they perform better than seedlings. This response is not coupled to adult vulnerability to drought for these species, revealing the difficulty of predicting species dynamics during climate change.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: climate change; Drought; mediterranean forest; Nitrogen use; phillyrea latifolia; Quercus ilex; Recruitment; Regeneration; Seedling; sprouting; water use efficiency

Estimation of foliage moisture content using near infrared reflectance spectroscopy - Gillon, D; Dauriac, F; Deshayes, M; Valette, J C; Moro, C (Agricultural and Forest Meteorology, 2004)
This study explored the relationships between the initial moisture content of leaves and their spectral properties when dry. Foliage moisture content (FMC in % dry-weight (DW)) was measured in 864 samples of eight common Mediterranean tree and shrub species from two sites during the summers of 2001 and 2002. All samples were dried, ground and scanned using a near infrared reﬂectance spectrophotometer. There were close relationships between FMC and foliage absorbance in the 400–2500 nm spectral range. Calibrations involving search for predictive relationships between spectral data and FMC were performed using partial least squares (PLS) regression that took into account all the spectral information. Calibration on FMC in each species from each year was predictive when a sufﬁciently large range of FMC values were available (R 2 = 0.93–0.99, standard error of cross-validation (SECV) = 2–7%). Moreover, calibration on FMC in all species combined, for each year or for both years together, was also predictive (R 2 = 0.92–0.95, SECV = 7%). It was thus possible to estimate the initial moisture content of a fresh foliage sample from its spectral characteristics when dried, whatever the species. However, mean foliage spectral absorbance changed from 1 year to the other. Consequently, FMC in leaf samples from each year was not estimated with accuracy when using the calibration established on samples from the other year but was accurately estimated when using the calibration established on samples from both years together. These close relations between dried foliage spectral data and FMC meant that some biochemical properties of the leaves associated with the changes in leaf water status caused changes in spectral reﬂectance which was preserved in the dried samples.
Keywords: foliage moisture content; infrared spectroscopy; mediterranean species; statistical calibration

Estimation of Mediterranean forest transpiration and photosynthesis through the use of an ecosystem simulation model driven by remotely sensed data - Anselmi, Silvia; Chiesi, Marta; Giannini, Monica; Manes, Fausto; Maselli, Fabio (Global Ecology and Biogeography, 2004)
Aim This paper investigates the use of an ecosystem simulation model, FOREST-BGC, to estimate the main ecophysiological processes (transpiration and photosynthesis) of Mediterranean coastal forest areas using remotely sensed data. Location Model testing was carried out at two protected forest sites in central Italy, one of which was covered by Turkey oak (Circeo National Park) and the other by holm-oak (Castelporziano Estate). Methods At both sites, transpiration and photosynthesis measurements were collected in the field during the growing seasons over a four-year period (1999 and 2001 for the Turkey oak; 1997, 1999 and 2000 for the holm-oak). Calibration of the model was obtained through combining information derived from ground measurements and remotely sensed data. In particular, remote sensing estimates of the Leaf Area Index derived from 1 × 1-km NOAA AVHRR Normalized Difference Vegetation Index data were used to improve the adaptation of the model to local forest conditions. Results The results indicated different strategies regarding water use efficiency, ‘water spending’ for Turkey oak and ‘water saving’ for holm-oak. The water use efficiency for the holm-oak was consistently higher than that for the Turkey oak and the relationship between VPD and WUE for the holm-oak showed a higher coefficient of determination (R2 = 0.9238). Comparisons made between the field measurements of transpiration and photosynthesis and the model estimates showed that the integration procedure used for the deciduous oak forest was effective, but that there is a need for further studies regarding the sclerophyllous evergreen forest. In particular, for Turkey oak the simulations of transpiration yielded very good results, with errors lower than 0.3 mm H2O/day, while the simulation accuracy for photosynthesis was lower. In the case of holm-oak, transpiration was markedly overestimated for all days considered, while the simulations of photosynthesis were very accurate. Main conclusions Overall, the approach offers interesting operational possibilities for the monitoring of Mediterranean forest ecosystems, particularly in view of the availability of new satellite sensors with a higher spatial and temporal resolution, which have been launched in recent years.
The following values have no corresponding Zotero field: publisher: Blackwell Science Ltd
Keywords: AVHRR; Ecosystem; FOREST-BGC; Mediterranean area; Modelling; photosynthesis; Quercus cerris; Quercus ilex; Transpiration; water efficiency

Estimation of Mediterranean forest transpiration and photosynthesis through the use of an ecosystem simulation model driven by remotely sensed data - Anselmi, Silvia; Chiesi, Marta; Giannini, Monica; Manes, Fausto; Maselli, Fabio (Global Ecology and Biogeography, 2004)
Aim This paper investigates the use of an ecosystem simulation model, FOREST-BGC, to estimate the main ecophysiological processes (transpiration and photosynthesis) of Mediterranean coastal forest areas using remotely sensed data. Location Model testing was carried out at two protected forest sites in central Italy, one of which was covered by Turkey oak (Circeo National Park) and the other by holm-oak (Castelporziano Estate). Methods At both sites, transpiration and photosynthesis measurements were collected in the field during the growing seasons over a four-year period (1999 and 2001 for the Turkey oak; 1997, 1999 and 2000 for the holm-oak). Calibration of the model was obtained through combining information derived from ground measurements and remotely sensed data. In particular, remote sensing estimates of the Leaf Area Index derived from 1 × 1-km NOAA AVHRR Normalized Difference Vegetation Index data were used to improve the adaptation of the model to local forest conditions. Results The results indicated different strategies regarding water use efficiency, ‘water spending’ for Turkey oak and ‘water saving’ for holm-oak. The water use efficiency for the holm-oak was consistently higher than that for the Turkey oak and the relationship between VPD and WUE for the holm-oak showed a higher coefficient of determination (R2 = 0.9238). Comparisons made between the field measurements of transpiration and photosynthesis and the model estimates showed that the integration procedure used for the deciduous oak forest was effective, but that there is a need for further studies regarding the sclerophyllous evergreen forest. In particular, for Turkey oak the simulations of transpiration yielded very good results, with errors lower than 0.3 mm H2O/day, while the simulation accuracy for photosynthesis was lower. In the case of holm-oak, transpiration was markedly overestimated for all days considered, while the simulations of photosynthesis were very accurate. Main conclusions Overall, the approach offers interesting operational possibilities for the monitoring of Mediterranean forest ecosystems, particularly in view of the availability of new satellite sensors with a higher spatial and temporal resolution, which have been launched in recent years.
Keywords: AVHRR; Ecosystem; FOREST-BGC; Mediterranean area; Modelling; photosynthesis; Quercus cerris; Quercus ilex; Transpiration; water efficiency

Estimation of plant diversity at landscape level: a methodological approach applied to three Spanish rural areas - Ortega, M. (Environmental Monitoring and Assessment, 2004)
Approaches linking biodiversity assessment with landscape structure are necessary in the framework of sustainable rural development. The present paper describes a methodology to estimate plant diversity involving landscape structure as a proportional weight associated with different plant communities found in the landscape mosaic. The area occupied by a plant community, its patch number or its spatial distribution of patches are variables that could be expressed in gamma plant diversity of a territory. The methodology applies (1) remote sensing information, to identify land cover and land use types; (2) aspect, to discriminate composition of plant communities in each land cover type; (3) multi-scale ﬁeld techniques, to asses plant diversity; (4) afﬁnity analysis of plant community composition, to validate the stratiﬁed random sampling design and (5) the additive model that partitions gamma diversity into its alpha and beta components. The method was applied to three Spanish rural areas and was able to record 150–260 species per ha. Species richness, Shannon information index and Simpson concentration index were used to measure diversity in each area. The estimation using Shannon diversity index and the product of patch number and patch interspersion as weighting of plant community diversity was found to be the most appropriate method of measuring plant diversity at the landscape level.
Keywords: landscape; Mediterranean vegetation; metrics; plant diversity; Remote sensing

Estimation of plant diversity at landscape level: a methodological approach applied to three Spanish rural areas - Ortega, M (Environmental Monitoring and Assessment, 2004)
Approaches linking biodiversity assessment with landscape structure are necessary in the framework of sustainable rural development. The present paper describes a methodology to estimate plant diversity involving landscape structure as a proportional weight associated with different plant communities found in the landscape mosaic. The area occupied by a plant community, its patch number or its spatial distribution of patches are variables that could be expressed in gamma plant diversity of a territory. The methodology applies (1) remote sensing information, to identify land cover and land use types; (2) aspect, to discriminate composition of plant communities in each land cover type; (3) multi-scale ﬁeld techniques, to asses plant diversity; (4) afﬁnity analysis of plant community composition, to validate the stratiﬁed random sampling design and (5) the additive model that partitions gamma diversity into its alpha and beta components. The method was applied to three Spanish rural areas and was able to record 150–260 species per ha. Species richness, Shannon information index and Simpson concentration index were used to measure diversity in each area. The estimation using Shannon diversity index and the product of patch number and patch interspersion as weighting of plant community diversity was found to be the most appropriate method of measuring plant diversity at the landscape level.
Keywords: landscape; Mediterranean vegetation; metrics; plant diversity; Remote sensing

Ethnopharmacology of ogliastra (villagrande strisaili, sardinia, Italy). - Loi, M. C.; Poli, F.; Sacchetti, G.; Selenu, M. B.; Ballero, M. (Fitoterapia, 2004)
The use of medicinal and aromatic plants was investigated in a group of 200 elderly people (60-104-year-old) from Villagrande Strisaili (Ogliastra, Sardinia, Italy), recording the use of 78 species for the treatment of various ailments, especially of the respiratory tract, the mouth, and the skin. Seventeen plants had never been described as medicinal species in peninsular Italy, while a few others turn out to have an original use for Sardinia.
The following values have no corresponding Zotero field: accession-num: 15158984
Keywords: Italy; Medicinal plants; ogliastra; Sardinia; Traditional phytotherapy; Villagrande Strisaili

Evaluation of biomass residuals in Portugal mainland - Dias, J.; Azevedo, J. L. T. (NEW AND RENEWABLE ENERGY TECHNOLOGIES FOR SUSTAINABLE DEVELOPMENT, 2004)
The increase of the share of renewable energy sources in Portugal can be met from different sources where biomass plays a main role. This paper presents an estimation of the quantity of biomass residuals from the forest, wood industry, agriculture and agro-industry. For the forest residues, three methodologies were used based on: i) Forest clear area, ii) Forest area and trees rotation and iii) Wood production. The values obtained are based on data from the wood forest in 1995 and in data from wood production, agriculture and agro-industry from 1997 to 1999. The total amount of pine and eucalyptus residues amounts to 650 - 1045 thousand tons/year in dry basis and is lower than other estimative from other authors. The differences obtained between the methods are analyzed as a function of the assumptions made and the relative merits. Additionally, the residues produced from holm oak and cork oak are estimated as 128 thousand dry ton/year. The wood industry and cork industry contributes with a residues production around 1584 thousand dry ton/year, while the total amounts of residues produced in agriculture and agro-industry are estimated as 2001 and 872 thousand dry tons/year, respectively. Considering technical and economical limitations and alternative utilization of biomass residues, the total amount available for combustion is estimated around 2628 thousand dry ton/year and it; seasonal distribution is identified.
The following values have no corresponding Zotero field: periodical: NEW AND RENEWABLE ENERGY TECHNOLOGIES FOR SUSTAINABLE DEVELOPMENT pub-location: SCHIPHOLWEG 107C, PO BOX 447, 2316 XC LEIDEN, NETHERLANDS
Keywords: biomass residuals; energy utilisation; renewable energy sources

Evaluation of biomass residuals in Portugal mainland - Dias, J; Azevedo, J L T (NEW AND RENEWABLE ENERGY TECHNOLOGIES FOR SUSTAINABLE DEVELOPMENT, 2004)
The increase of the share of renewable energy sources in Portugal can be met from different sources where biomass plays a main role. This paper presents an estimation of the quantity of biomass residuals from the forest, wood industry, agriculture and agro-industry. For the forest residues, three methodologies were used based on: i) Forest clear area, ii) Forest area and trees rotation and iii) Wood production. The values obtained are based on data from the wood forest in 1995 and in data from wood production, agriculture and agro-industry from 1997 to 1999. The total amount of pine and eucalyptus residues amounts to 650 - 1045 thousand tons/year in dry basis and is lower than other estimative from other authors. The differences obtained between the methods are analyzed as a function of the assumptions made and the relative merits. Additionally, the residues produced from holm oak and cork oak are estimated as 128 thousand dry ton/year. The wood industry and cork industry contributes with a residues production around 1584 thousand dry ton/year, while the total amounts of residues produced in agriculture and agro-industry are estimated as 2001 and 872 thousand dry tons/year, respectively. Considering technical and economical limitations and alternative utilization of biomass residues, the total amount available for combustion is estimated around 2628 thousand dry ton/year and it; seasonal distribution is identified.
Keywords: biomass residuals; energy utilisation; renewable energy sources

EXPERIENCIA DE REGENERACIÓN DE ENCINAR EN LA SIERRA DE HUELVA Studies on holm oak regeneration in North Sevilla mountains - Porras Tejeiro, C J; Brun Esquiliche, P; Copete Gutiérrez, J; Pérez Méndez, R (Cuad. Soc. Esp. Cien. For Actas de la III Reunión sobre Repoblaciones Forestales, 2004)
We have described an oak regeneration research without prohibit the grazing. Three implantation types and seven protections types have been tested. Several parameters have been measured to the seven, fifteen and twenty three months since the seeding or planting
Keywords: Dehesa; Grazing; implantación; Implantation; pastoreo; protección; Protection; Quercus

EXPERIENCIA DE REGENERACIÓN DE ENCINAR EN LA SIERRA DE HUELVA Studies on holm oak regeneration in North Sevilla mountains - Porras Tejeiro, C. J.; Brun Esquiliche, P.; Copete Gutiérrez, J.; Pérez Méndez, R. (Cuad. Soc. Esp. Cien. For Actas de la III Reunión sobre Repoblaciones Forestales, 2004)
We have described an oak regeneration research without prohibit the grazing. Three implantation types and seven protections types have been tested. Several parameters have been measured to the seven, fifteen and twenty three months since the seeding or planting
Keywords: Dehesa; Grazing; implantación; Implantation; pastoreo; protección; Protection; Quercus

Extensively reared Iberian pigs versus intensively reared white pigs for the manufacture of liver pâté. - Estévez, M.; Morcuende, D.; Ramírez, R.; Ventanas, J.; Cava, R. (Meat science, 2004)
Physico-chemical characteristics and quality traits of the raw ingredients (muscle cuadriceps femoris, liver and adipose tissue) and the pâtés made from extensively reared Iberian pigs and intensively reared white pigs, were evaluated. The differences found between muscles, livers and adipose tissues from Iberian and white pigs influenced the characteristics of the pâtés. Compared to pâtés from white pigs, pâtés from Iberian pigs had a higher content of heme iron (27.5 μg/g vs 11.5 μg/g; p<0.05) and lower content of non-heme iron (27.5 μg/g vs 33.7 μg/g; p<0.05). Pâtés from Iberian pigs exhibited a darker colour (L (∗):18.6 vs 15.9, p<0.05) with less redness (a (∗) values: 9.1 vs 11.3; p<0.05) and yellowness (b (∗) values: 13.1 vs 14.8, p<0.05). Thus, pâtés from white pigs had higher values of chroma (18.6 vs 15.9, p<0.05) and smaller values of hue (52.5 vs 55.2, p<0.05) that those from Iberian pigs' pâtés. In fatty acid composition, pâtés from white pigs had higher proportions of SFA (37.9% vs 32.8%, p<0.05) and PUFA (14.4% vs 9.6%, p<0.05) than pâtés from Iberian pigs and lower percentages of oleic (53.4% vs 43.6%, p<0.05) and total of MUFA (57.5% vs 47.6%, p<0.05). Pâtés from Iberian pigs had a lower n-6/n-3 values (13.2 vs 17.2; p<0.05).
The following values have no corresponding Zotero field: accession-num: 22061520
Keywords: Extensive; fatty acids; Iberian pigs; Instrumental colour; Iron; liver p; liver paté; White pigs

Extensively reared Iberian pigs versus intensively reared white pigs for the manufacture of liver pâté. - Estévez, M; Morcuende, D; Ramírez, R; Ventanas, J; Cava, R (Meat science, 2004)
Physico-chemical characteristics and quality traits of the raw ingredients (muscle cuadriceps femoris, liver and adipose tissue) and the pâtés made from extensively reared Iberian pigs and intensively reared white pigs, were evaluated. The differences found between muscles, livers and adipose tissues from Iberian and white pigs influenced the characteristics of the pâtés. Compared to pâtés from white pigs, pâtés from Iberian pigs had a higher content of heme iron (27.5 μg/g vs 11.5 μg/g; p<0.05) and lower content of non-heme iron (27.5 μg/g vs 33.7 μg/g; p<0.05). Pâtés from Iberian pigs exhibited a darker colour (L (∗):18.6 vs 15.9, p<0.05) with less redness (a (∗) values: 9.1 vs 11.3; p<0.05) and yellowness (b (∗) values: 13.1 vs 14.8, p<0.05). Thus, pâtés from white pigs had higher values of chroma (18.6 vs 15.9, p<0.05) and smaller values of hue (52.5 vs 55.2, p<0.05) that those from Iberian pigs' pâtés. In fatty acid composition, pâtés from white pigs had higher proportions of SFA (37.9% vs 32.8%, p<0.05) and PUFA (14.4% vs 9.6%, p<0.05) than pâtés from Iberian pigs and lower percentages of oleic (53.4% vs 43.6%, p<0.05) and total of MUFA (57.5% vs 47.6%, p<0.05). Pâtés from Iberian pigs had a lower n-6/n-3 values (13.2 vs 17.2; p<0.05).
Keywords: Extensive; fatty acids; Iberian pigs; Instrumental colour; Iron; liver p; liver paté; White pigs

Farming practices and Roller Coracias garrulus conservation in south-west Spain - Aviles, J. M.; Parejo, D. (BIRD CONSERVATION INTERNATIONAL, 2004)
There are no previous studies supporting the link between the decline of Roller Coracias garrulus populations in the Palaearctic and agricultural intensification. We studied the effect of farming practices on Roller reproduction during 1988-1991 in south-west Spain. Nest-boxes were installed on power pylons that crossed six different man-made habitats representing the most characteristic habitats in the Mediterranean region: pasture fields with and without holm oak Quercus roffindifolia trees, cereal fields with and without holm oak trees, scrub fields and irrigated fields. Rollers nesting in nest-boxes erected in unwooded pasture field had the highest breeding success, suggesting that this is the most suitable nesting habitat of Rollers in the region. There were no significant effects of farming practices in habitat adjacent to nests on Roller laying date and clutch size. However, after controlling for laying date, current agricultural practices around nests affected chick mortality, with higher losses in irrigated fields. Breeding success and egg productivity were also affected by farming activities, with the lowest values in irrigated fields. Future conservation plans for Rollers should consider that nest-box provision might increase habitat suitability for Roller reproduction and that highly intensified agricultural practices might have deleterious effects on Roller populations.
APSAPSThe following values have no corresponding Zotero field: pub-location: 40 WEST 20TH ST, NEW YORK, NY 10011-4211 USA publisher: CAMBRIDGE UNIV PRESS
Keywords: Agricultural intensification; farming practices; Mediterranean; nest-boxes; reproduction; Roller Coracias garrulus

Farming practices and Roller Coracias garrulus conservation in south-west Spain - Aviles, J M; Parejo, D (BIRD CONSERVATION INTERNATIONAL, 2004)
There are no previous studies supporting the link between the decline of Roller Coracias garrulus populations in the Palaearctic and agricultural intensification. We studied the effect of farming practices on Roller reproduction during 1988-1991 in south-west Spain. Nest-boxes were installed on power pylons that crossed six different man-made habitats representing the most characteristic habitats in the Mediterranean region: pasture fields with and without holm oak Quercus roffindifolia trees, cereal fields with and without holm oak trees, scrub fields and irrigated fields. Rollers nesting in nest-boxes erected in unwooded pasture field had the highest breeding success, suggesting that this is the most suitable nesting habitat of Rollers in the region. There were no significant effects of farming practices in habitat adjacent to nests on Roller laying date and clutch size. However, after controlling for laying date, current agricultural practices around nests affected chick mortality, with higher losses in irrigated fields. Breeding success and egg productivity were also affected by farming activities, with the lowest values in irrigated fields. Future conservation plans for Rollers should consider that nest-box provision might increase habitat suitability for Roller reproduction and that highly intensified agricultural practices might have deleterious effects on Roller populations.
APS
Keywords: Agricultural intensification; farming practices; Mediterranean; nest-boxes; reproduction; Roller Coracias garrulus

Frost resistance of seeds in Mediterranean oaks and the role of litter - Esteso-Martínez, Jordán; Gil-Pelegrín, Eustaquio (Ann. For. Sci., 2004)
The endogenous frost resistance of the seeds of four Mediterranean oaks (Quercus coccifera, Q. faginea, Q. ilex and Q. pyrenaica) with different leaf abscission phenology was tested. Thermal analysis and polyelectrolytes leakage methodologies were employed to establish lethal temperature thresholds. Results showed a higher frost resistance for evergreen species and lower for deciduous species in this decreasing order: Q. coccifera, Q. ilex, Q. faginea and Q. pyrenaica. The cover of leaf litter generated by deciduous species could be an isolating element which allowed seed survival under cold winter conditions to that species with a lower frost resistance. Differences in temperature above and below a leaf litter cover along a winter season were measured in a Q. faginea stand, in this sense the kind effect of leaf litter from a thermal point of view was proved.
Keywords: frost resistance; leaf litter; polyelectrolytic leakage; Quercus; thermal analysis

Frost resistance of seeds in Mediterranean oaks and the role of litter - Esteso-Martínez, Jordán; Gil-Pelegrín, Eustaquio (Ann. For. Sci., 2004)
The endogenous frost resistance of the seeds of four Mediterranean oaks (Quercus coccifera, Q. faginea, Q. ilex and Q. pyrenaica) with different leaf abscission phenology was tested. Thermal analysis and polyelectrolytes leakage methodologies were employed to establish lethal temperature thresholds. Results showed a higher frost resistance for evergreen species and lower for deciduous species in this decreasing order: Q. coccifera, Q. ilex, Q. faginea and Q. pyrenaica. The cover of leaf litter generated by deciduous species could be an isolating element which allowed seed survival under cold winter conditions to that species with a lower frost resistance. Differences in temperature above and below a leaf litter cover along a winter season were measured in a Q. faginea stand, in this sense the kind effect of leaf litter from a thermal point of view was proved.
Keywords: frost resistance; leaf litter; polyelectrolytic leakage; Quercus; thermal analysis

Genetic transformation of selected mature cork oak (Quercus suber L.) trees. - Alvarez, R.; Alonso, P.; Cortizo, M.; Celestino, C.; Hernández, I.; Toribio, M.; Ordás, R. J. (Plant cell reports, 2004)
A transformation system for selected mature cork oak (Quercus suber L.) trees using Agrobacterium tumefaciens has been established. Embryos obtained from recurrent proliferating embryogenic masses were inoculated with A. tumefaciens strains EHA105, LBA4404 or AGL1 harbouring the plasmid pBINUbiGUSint [carrying the neomycin phosphotransferase II (nptII) and beta-glucuronidase (uidA) genes]. The highest transformation efficiency (4%) was obtained when freshly isolated explants were inoculated with A. tumefaciens strain AGL1. Evidence of stable transgene integration was obtained by PCR for the nptII and uidA genes, Southern blotting and expression of the uidA gene. The transgenic embryos were germinated and successfully transferred to soil.
The following values have no corresponding Zotero field: accession-num: 15185122
Keywords: Agrobacterium; Cork oak; Fagaceae; Somatic embryogenesis; Tree genetic transformation

Genetic transformation of selected mature cork oak (Quercus suber L.) trees. - Álvarez, R; Alonso, P; Cortizo, M; CELESTINO, C; HERNÁNDEZ, I; TORIBIO, M; Ordás, R J (Plant cell reports, 2004)
A transformation system for selected mature cork oak (Quercus suber L.) trees using Agrobacterium tumefaciens has been established. Embryos obtained from recurrent proliferating embryogenic masses were inoculated with A. tumefaciens strains EHA105, LBA4404 or AGL1 harbouring the plasmid pBINUbiGUSint [carrying the neomycin phosphotransferase II (nptII) and beta-glucuronidase (uidA) genes]. The highest transformation efficiency (4%) was obtained when freshly isolated explants were inoculated with A. tumefaciens strain AGL1. Evidence of stable transgene integration was obtained by PCR for the nptII and uidA genes, Southern blotting and expression of the uidA gene. The transgenic embryos were germinated and successfully transferred to soil.
Keywords: Agrobacterium; Cork oak; Fagaceae; Somatic embryogenesis; Tree genetic transformation

Geographical variation in the potential of mice to constrain an ant-seed dispersal mutualism - Fedriani, J. M.; Rey, P. J.; Garrido, J. L.; Guitián, J.; Herrera, C. M.; Medrano, M.; Sánchez-Lafuente, A. M.; Cerdá, X. (Oikos, 2004)
Pre- and post-dispersal Helleborus foetidus (Ranunculaceae) seed predation by mice Apodemus sylvaticus as well as post-dispersal seed removal by ants was studied, during two years, in six plant populations within three geographical regions (Caurel, Cazorla and Mágina) of the Iberian Peninsula. An observational approach revealed strong interregional differences in seed predation by mice during the pre-dispersal phase, with high and similar rates of predation in Cazorla and Mágina and much lower rates in Caurel. There were also significant inter-annual variations on pre-dispersal seed predation by mice, while the existing habitat-related differences (of lower magnitude) were not consistent across regions. Field experiments based on seed-offering exclosures, showed that, despite some interregional variation, post-dispersal seed removal by ants was consistently high through all spatial and temporal scales considered, with most seeds being removed within 48 h. Conversely, post-dispersal seed predation by mice was highly variable among regions, being very high in Cazorla and minimal or absent in Caurel and Mágina. Interestingly, in Cazorla, in presence of mice, the number of seeds removed was rather independent of the presence/absence of ants, while under mice exclusion, it was determined by the presence/absence of ants. Conversely, in Caurel, the number of seeds removed by each remover agent (ants or mice) was independent of the presence/absence of the other agent. Thus, though uniquely in Cazorla, mice limited the number of seeds available to ants and, therefore, in this region could potentially have interfered on the development of seed traits that enable ants to efficiently harvest them. Our results support the notion that geographical variation over the Iberian Peninsula of mice seed predation may have promoted a mosaic of well-matching and mismatching situations between H. foetidus diaspore traits and the characteristics of ant communities, which is consistent with some recent theories on the geographical structure of interactions.
The following values have no corresponding Zotero field: publisher: Munksgaard
Keywords: ant-plant mutualism (voyant); seed dispersal; seed predation

Geographical variation in the potential of mice to constrain an ant-seed dispersal mutualism - Fedriani, J M; Rey, P J; Garrido, J L; Guitián, J; Herrera, C M; Medrano, M; Sánchez-Lafuente, A M; Cerdá, X (Oikos, 2004)
Pre- and post-dispersal Helleborus foetidus (Ranunculaceae) seed predation by mice Apodemus sylvaticus as well as post-dispersal seed removal by ants was studied, during two years, in six plant populations within three geographical regions (Caurel, Cazorla and Mágina) of the Iberian Peninsula. An observational approach revealed strong interregional differences in seed predation by mice during the pre-dispersal phase, with high and similar rates of predation in Cazorla and Mágina and much lower rates in Caurel. There were also significant inter-annual variations on pre-dispersal seed predation by mice, while the existing habitat-related differences (of lower magnitude) were not consistent across regions. Field experiments based on seed-offering exclosures, showed that, despite some interregional variation, post-dispersal seed removal by ants was consistently high through all spatial and temporal scales considered, with most seeds being removed within 48 h. Conversely, post-dispersal seed predation by mice was highly variable among regions, being very high in Cazorla and minimal or absent in Caurel and Mágina. Interestingly, in Cazorla, in presence of mice, the number of seeds removed was rather independent of the presence/absence of ants, while under mice exclusion, it was determined by the presence/absence of ants. Conversely, in Caurel, the number of seeds removed by each remover agent (ants or mice) was independent of the presence/absence of the other agent. Thus, though uniquely in Cazorla, mice limited the number of seeds available to ants and, therefore, in this region could potentially have interfered on the development of seed traits that enable ants to efficiently harvest them. Our results support the notion that geographical variation over the Iberian Peninsula of mice seed predation may have promoted a mosaic of well-matching and mismatching situations between H. foetidus diaspore traits and the characteristics of ant communities, which is consistent with some recent theories on the geographical structure of interactions.
Keywords: ant-plant mutualism (voyant); seed dispersal; seed predation

Growth of forest plants (pine and holm-oak) inoculated with rhizobacteria: relationship with microbial community structure and biological activity of its rhizosphere - Garcı́a, Jose A. Lucas; Domenech, Jezabel; Santamarı́a, Carmen; Camacho, Marı́a; Daza, Antonio; Mañero, F. Javier Gutierrez (Environmental and Experimental Botany, 2004)
Four bacterial strains showing in vitro metabolic capacities related to their plant growth-promoting action (plant growthpromoting rhizobacteria (PGPRs)) were studied in the growth of holm-oak (Quercus ilex ssp. Ballota) and pine (Pinus pinea) plants at a forest nursery before outplanting. All strains signiﬁcantly increased some of the parameters studied (stem length, neck diameter and shoot dry weight), although, neck root diameter showed the smallest increase in general. An interaction plant/bacterial strain was observed. Some strains speciﬁcally increased aerial parameters in both plant species, whereas other strains did so mainly in one plant species. Analyses of PLFAs and incorporation of thymidine and leucine suggest differences in the perturbation of microbial communities previously established and in the capacity of adaptation to the rhizosphere environment among the different strains
Keywords: colonisation; PGPR; Pinus pinea; plfas; Quercus ilex ssp. ballota; rhizosphere; thymidine leucine incorporation

Growth of forest plants (pine and holm-oak) inoculated with rhizobacteria: relationship with microbial community structure and biological activity of its rhizosphere - Garcı́a, Jose A.Lucas; Domenech, Jezabel; Santamarı́a, Carmen; Camacho, Marı́a; Daza, Antonio; Mañero, F.Javier Gutierrez (Environmental and Experimental Botany, 2004)
Four bacterial strains showing in vitro metabolic capacities related to their plant growth-promoting action (plant growthpromoting rhizobacteria (PGPRs)) were studied in the growth of holm-oak (Quercus ilex ssp. Ballota) and pine (Pinus pinea) plants at a forest nursery before outplanting. All strains signiﬁcantly increased some of the parameters studied (stem length, neck diameter and shoot dry weight), although, neck root diameter showed the smallest increase in general. An interaction plant/bacterial strain was observed. Some strains speciﬁcally increased aerial parameters in both plant species, whereas other strains did so mainly in one plant species. Analyses of PLFAs and incorporation of thymidine and leucine suggest differences in the perturbation of microbial communities previously established and in the capacity of adaptation to the rhizosphere environment among the different strains
Keywords: colonisation; PGPR; Pinus pinea; plfas; Quercus ilex ssp. ballota; rhizosphere; thymidine leucine incorporation

Growth response to ozone of annual species from Mediterranean pastures. - Gimeno, B S; Bermejo, V; Sanz, J; de la Torre, D; Elvira, S (Environmental pollution (Barking, Essex : 1987), 2004)
Ozone (O3) phytotoxicity has been reported on a wide range of plant species. However, scarce information has been provided regarding the sensitivity of semi-natural grassland species, especially those from dehesa Mediterranean grasslands, in spite of their great biological diversity and the high O3 levels recorded in the region. A screening study was carried out in open-top chambers (OTCs) to assess the O3-sensitivity of representative therophytes of these ecosystems based on the response of selected growth-related parameters. Three O3 treatments and 3 OTCs per treatment were used. Legume species were very sensitive to O3, because 78% of the tested species showed detrimental effects on their total biomass relative growth rate (RGR) following their exposure to O3. The Trifolium genus was particularly sensitive showing O3-induced adverse effects on most of the assessed parameters. Gramineae plants were less sensitive than Leguminosae species because detrimental effects on total biomass RGR were only observed in 14% of the assessed species. No relationship was found between relative growth rates when growing in clean air and O3 susceptibility. The implications of these effects on the performance of dehesa acidic grasslands and on the definition of ozone critical levels for the protection of semi-natural vegetation are discussed.
Keywords: Critical levels; Dehesa; Relative growth rate; Screening; Therophytes

Habitat quality as a predictor of spatial variation in blue tit reproductive performance: a multi-plot analysis in a heterogeneous landscape - Lambrechts, MarcelM; Caro, Samuel; Charmantier, Anne; Gross, Nicolas; Galan, Marie-Jo; Perret, Philippe; Cartan-Son, Mireille; Dias, PaulaC; Blondel, Jacques; Thomas, DonaldW (Oecologia, 2004)
Vertebrate studies have rarely investigated the influence of spatial variation in habitat richness on both short-term (breeding) and long-term (offspring recruitment) reproductive performance using simultaneously multi-patch, multi-habitat type and multi-year approaches at landscape level. Here we present results of such an approach using the influence of two oak tree (Quercus ilex, Q. humilis) species on reproductive performance in Corsican blue tits (Parus caeruleus ogliastrae) as a model system. We found that blue tits breeding in rich broadleaved deciduous patches consistently laid eggs earlier in the season, and produced larger clutches and more fledglings of higher quality, than those breeding in poor evergreen patches. Also, parents, especially males, were in better physical condition in the broad-leaved deciduous than in the evergreen patches. Surprisingly, estimates of long-term effects of reproduction, such as recruitment rates of locally born offspring, did not differ between the two habitat types. Our results suggest that short-term breeding performance and phenotypic quality of both chicks and parents do not necessarily provide reliable information about contributions to following generations at a scale larger than that of the local study plot. Differences in reproductive performance between the two oak habitat types could not be attributed to densitydependent effects, differences in levels of nest predation, or differences in age structure of the birds. We suggest that habitats that are optimal for breeding are not necessarily optimal for survival after the breeding season.
The following values have no corresponding Zotero field: publisher: Springer-Verlag
Keywords: Habitat quality; Parus caeruleus; Predation; Quercus; reproduction

Habitat quality as a predictor of spatial variation in blue tit reproductive performance: a multi-plot analysis in a heterogeneous landscape - Lambrechts, MarcelM.; Caro, Samuel; Charmantier, Anne; Gross, Nicolas; Galan, Marie-Jo; Perret, Philippe; Cartan-Son, Mireille; Dias, PaulaC.; Blondel, Jacques; Thomas, DonaldW. (Oecologia, 2004)
Vertebrate studies have rarely investigated the influence of spatial variation in habitat richness on both short-term (breeding) and long-term (offspring recruitment) reproductive performance using simultaneously multi-patch, multi-habitat type and multi-year approaches at landscape level. Here we present results of such an approach using the influence of two oak tree (Quercus ilex, Q. humilis) species on reproductive performance in Corsican blue tits (Parus caeruleus ogliastrae) as a model system. We found that blue tits breeding in rich broadleaved deciduous patches consistently laid eggs earlier in the season, and produced larger clutches and more fledglings of higher quality, than those breeding in poor evergreen patches. Also, parents, especially males, were in better physical condition in the broad-leaved deciduous than in the evergreen patches. Surprisingly, estimates of long-term effects of reproduction, such as recruitment rates of locally born offspring, did not differ between the two habitat types. Our results suggest that short-term breeding performance and phenotypic quality of both chicks and parents do not necessarily provide reliable information about contributions to following generations at a scale larger than that of the local study plot. Differences in reproductive performance between the two oak habitat types could not be attributed to densitydependent effects, differences in levels of nest predation, or differences in age structure of the birds. We suggest that habitats that are optimal for breeding are not necessarily optimal for survival after the breeding season.
Keywords: Habitat quality; Parus caeruleus; Predation; Quercus; reproduction

Holm oak (Quercus rotundifolia Lam.) and Aleppo pine (Pinus halepensis Mill.) response to different soil preparation techniques applied to forestation in abandoned farmland - Bocio, Inmaculada; Navarro, Francisco Bruno; Ripoll, María Angeles; Jiménez, María Noelia; Simón, Estanislao De (Ann. For. Sci., 2004)
This paper evaluates the effectiveness of several soil preparation procedures in forestation establishment and development in localized farmland, within a territory in ombroclimatic transition between dry and semi-arid, located in Granada, southeastern Spain. An experiment in the forestation of Holm oak (Quercus rotundifolia Lam.) and Aleppo pine (Pinus halepensis Mill.) was set up, in which 8 different soil preparation techniques were used. The survival, total height and basal diameter of the plantation was monitored over a 5-year period (1996-2000). The statistical analysis of these parameters evidenced highly significant differences in the overall behaviour of the two sample forest species, related to changes in the prevailing environmental conditions in these territories and the type of soil preparation procedure applied. The overall results obtained for the three parameters analysed show the effectiveness of using backhoes for pit planting and linear rippering with a hydraulic structure to captures runoffs, in comparison to other preparations. Areal soil preparations, in particular, are not recommended.
Keywords: forestation; semi-arid; soil preparation

Holm oak (Quercus rotundifolia Lam.) and Aleppo pine (Pinus halepensis Mill.) response to different soil preparation techniques applied to forestation in abandoned farmland - Bocio, Inmaculada; Navarro, Francisco Bruno; Ripoll, María Angeles; Jiménez, María Noelia; Simón, Estanislao De (Ann. For. Sci., 2004)
This paper evaluates the effectiveness of several soil preparation procedures in forestation establishment and development in localized farmland, within a territory in ombroclimatic transition between dry and semi-arid, located in Granada, southeastern Spain. An experiment in the forestation of Holm oak (Quercus rotundifolia Lam.) and Aleppo pine (Pinus halepensis Mill.) was set up, in which 8 different soil preparation techniques were used. The survival, total height and basal diameter of the plantation was monitored over a 5-year period (1996-2000). The statistical analysis of these parameters evidenced highly significant differences in the overall behaviour of the two sample forest species, related to changes in the prevailing environmental conditions in these territories and the type of soil preparation procedure applied. The overall results obtained for the three parameters analysed show the effectiveness of using backhoes for pit planting and linear rippering with a hydraulic structure to captures runoffs, in comparison to other preparations. Areal soil preparations, in particular, are not recommended.
Keywords: forestation; semi-arid; soil preparation

How plant functional-type, weather, seasonal drought, and soil physical properties alter water and energy fluxes of an oak–grass savanna and an annual grassland - Baldocchi, Dennis D; Xu, Liukang; Kiang, Nancy (Agricultural and Forest Meteorology, 2004)
Savannas and open grasslands often co-exist in semi-arid regions. Questions that remain unanswered and are of interest to biometeorologists include: how do these contrasting landscapes affect the exchanges of energy on seasonal and annual time scales; and, do biophysical constraints imposed by water supply and water demand affect whether the land is occupied by open grasslands or savanna? To address these questions, and others, we examine how a number of abiotic, biotic and edaphic factors modulate water and energy ﬂux densities over an oak–grass savanna and an annual grassland that coexist in the same climate but on soils with different hydraulic properties. The net radiation balance was greater over the oak woodland than the grassland, despite the fact that both canopies received similar sums of incoming short and long wave radiation. The lower albedo and lower radiative surface temperature of the transpiring woodland caused it to intercept and retain more long and shortwave energy over the course of the year, and particularly during the summer dry period. The partitioning of available energy into sensible and latent heat exchanged over the two canopies differed markedly. The annual sum of sensible heat exchange over the woodland was 40% greater than that over the grassland (2.05 GJ m−2 per year versus 1.46 GJ m−2 per year). With regards to evaporation, the oak woodland evaporated about 380 mm of water per year and the grassland evaporated about 300 mm per year. Differences in available energy, canopy roughness, the timing of physiological functioning, water holding capacity of the soil and rooting depth of the vegetation explained the observed differences in sensible and latent heat exchange of the contrasting vegetation surfaces. The response of canopy evaporation to diminishing soil moisture was quantiﬁed by comparing normalized evaporation rates (in terms of equilibrium evaporation) with soil water potential and volumetric water content measurements. When soil moisture was ample normalized values of latent heat ﬂux density were greater for the grassland (1.1–1.2) than for the oak savanna (0.7–0.8) and independent of moisture content. Normalized rates of evaporation over the grassland declined as volumetric water content dropped below 0.15 m3 m−3 , which corresponded with a soil water potential of −1.5 MPa. The grassland senesced and quit transpiring when the volumetric water content of the soil dropped below −2.0 MPa. The oak trees, on the other hand, were able to transpire, albeit at low rates, under very dry soil conditions (soil water potentials below −4.0 MPa). The trees were able to endure such low water potentials and maintain basal levels of metabolism because ecological forcings kept the tree density and leaf area index of the woodland low, physiological factors forced the stomata to close progressively and the trees were able to tap deeper water sources (below 0.6 m) than the grasses.
Keywords: Biosphere–atmosphere interactions; ecohydrology; evaporation

How plant functional-type, weather, seasonal drought, and soil physical properties alter water and energy fluxes of an oak–grass savanna and an annual grassland - Baldocchi, Dennis D.; Xu, Liukang; Kiang, Nancy (Agricultural and Forest Meteorology, 2004)
Savannas and open grasslands often co-exist in semi-arid regions. Questions that remain unanswered and are of interest to biometeorologists include: how do these contrasting landscapes affect the exchanges of energy on seasonal and annual time scales; and, do biophysical constraints imposed by water supply and water demand affect whether the land is occupied by open grasslands or savanna? To address these questions, and others, we examine how a number of abiotic, biotic and edaphic factors modulate water and energy ﬂux densities over an oak–grass savanna and an annual grassland that coexist in the same climate but on soils with different hydraulic properties. The net radiation balance was greater over the oak woodland than the grassland, despite the fact that both canopies received similar sums of incoming short and long wave radiation. The lower albedo and lower radiative surface temperature of the transpiring woodland caused it to intercept and retain more long and shortwave energy over the course of the year, and particularly during the summer dry period. The partitioning of available energy into sensible and latent heat exchanged over the two canopies differed markedly. The annual sum of sensible heat exchange over the woodland was 40% greater than that over the grassland (2.05 GJ m−2 per year versus 1.46 GJ m−2 per year). With regards to evaporation, the oak woodland evaporated about 380 mm of water per year and the grassland evaporated about 300 mm per year. Differences in available energy, canopy roughness, the timing of physiological functioning, water holding capacity of the soil and rooting depth of the vegetation explained the observed differences in sensible and latent heat exchange of the contrasting vegetation surfaces. The response of canopy evaporation to diminishing soil moisture was quantiﬁed by comparing normalized evaporation rates (in terms of equilibrium evaporation) with soil water potential and volumetric water content measurements. When soil moisture was ample normalized values of latent heat ﬂux density were greater for the grassland (1.1–1.2) than for the oak savanna (0.7–0.8) and independent of moisture content. Normalized rates of evaporation over the grassland declined as volumetric water content dropped below 0.15 m3 m−3 , which corresponded with a soil water potential of −1.5 MPa. The grassland senesced and quit transpiring when the volumetric water content of the soil dropped below −2.0 MPa. The oak trees, on the other hand, were able to transpire, albeit at low rates, under very dry soil conditions (soil water potentials below −4.0 MPa). The trees were able to endure such low water potentials and maintain basal levels of metabolism because ecological forcings kept the tree density and leaf area index of the woodland low, physiological factors forced the stomata to close progressively and the trees were able to tap deeper water sources (below 0.6 m) than the grasses.
Keywords: Biosphere–atmosphere interactions; ecohydrology; evaporation

Identification of Portuguese Armillaria Isolates by Classic Mating-Tests and RFLP-PCR Analysis of the ITS1 Region of Ribosomal DNA - Bragança, Helena; Tenreiro, Rogério; Santos, Natércia (Silva Lusitana, 2004)
The diagnosis of Armillaria, a genus including distinct species of highly woody plantpathogenic root-infecting fungi with worldwide distribution, is usually based on morphological characteristics and mating-tests, although the PCR-based restriction fragment length polymorphism (RFLP-PCR), specifically in nuclear rDNA spacers, have also been applied. In the present study, mating-tests and restriction analysis of Internal Transcribed Spacer 1 (ITS1) were used to identify 20 isolates of a Portuguese Armillaria collection. Although the majority of the diploid isolates (80%) could be identified in diploid-haploid pairings, the method is laborious, takes too much time (up to 2 months), and presents a high rate of inconclusive results. The ITS1 region showed to be a reliable molecular marker for A. mellea, in particular when HinfI restriction analysis is applied, since two fragments with 245 bp and 125 bp have been obtained for this most aggressive species whereas 290 bp and 70 bp were produced from isolates of the other European species. As simple molecular techniques are involved and the whole procedure can be performed in one day, A. mellea identification by ITS1 analysis is a clearly accessible and more advantageous tool to plant pathology laboratories, mainly those involved on the control and preservation of forest trees
The following values have no corresponding Zotero field: publisher: scielopt
Keywords: Armillaria mellea; Cork oak; rDNA; RFLP-PCR; Woody plants

Identification of Portuguese Armillaria Isolates by Classic Mating-Tests and RFLP-PCR Analysis of the ITS1 Region of Ribosomal DNA - Bragança, Helena; Tenreiro, Rogério; Santos, Natércia (Silva Lusitana, 2004)
The diagnosis of Armillaria, a genus including distinct species of highly woody plantpathogenic root-infecting fungi with worldwide distribution, is usually based on morphological characteristics and mating-tests, although the PCR-based restriction fragment length polymorphism (RFLP-PCR), specifically in nuclear rDNA spacers, have also been applied. In the present study, mating-tests and restriction analysis of Internal Transcribed Spacer 1 (ITS1) were used to identify 20 isolates of a Portuguese Armillaria collection. Although the majority of the diploid isolates (80%) could be identified in diploid-haploid pairings, the method is laborious, takes too much time (up to 2 months), and presents a high rate of inconclusive results. The ITS1 region showed to be a reliable molecular marker for A. mellea, in particular when HinfI restriction analysis is applied, since two fragments with 245 bp and 125 bp have been obtained for this most aggressive species whereas 290 bp and 70 bp were produced from isolates of the other European species. As simple molecular techniques are involved and the whole procedure can be performed in one day, A. mellea identification by ITS1 analysis is a clearly accessible and more advantageous tool to plant pathology laboratories, mainly those involved on the control and preservation of forest trees
Keywords: Armillaria mellea; Cork oak; rDNA; RFLP-PCR; Woody plants

An improved neural network technique for data dimensionality reduction in remotely sensed imagery - Idrissi, M Janati; Sbihi, A; Touahni, R (International Journal of Remote Sensing, 2004)
An approach for non-linear projection of multidimensional data is discussed with application to remotely sensed imagery. The approach uses a multi-layer neural network in auto-associative mode with an improved updating rule, based on a conjugate gradient. To evaluate the usefulness of the proposed approach, we used the maximum likelihood classifier applied to a Landsat TM image of Kénitra region (Morocco).
doi: 10.1080/01431160110069881
Keywords: data dimensionality reduction; Neural networks; non-linear projection (voyant); Remote sensing

Increasing drought decreases phosphorus availability in an evergreen Mediterranean forest - Sardans, Jordi; Penuelas, Josep (Plant and Soil, 2004)
Mediterranean ecosystems are water-limited and frequently also nutrient-limited. We aimed to investigate the effects of increasing drought, as predicted by GCM and eco-physiological models for the next decades, on the P cycle and P plant availability in a Mediterranean forest. We conducted a ﬁeld experiment in a mature evergreen oak forest, establishing four drought-treatment plots and four control plots (150 m2 each). After three years, the runoff and rainfall exclusion reduced an overall 22% the soil moisture, and the runoff exclusion alone reduced it 10%. The reduction of 22% in soil moisture produced a decrease of 40% of the accumulated aboveground plant P content, above all because there was a smaller increase in aerial biomass. The plant leaf P content increased by 100 ± 40 mg m−2 in the control plots, whereas it decreased by 40 ± 40 mg m−2 in the drought plots. The soil Po-NaHCO3 (organic labile-P fraction) increased by 25% in consonance with the increase in litterfall, while the inorganic labile-P fraction decreased in relation to the organic labile-P fraction up to 48%, indicating a decrease in microbial activity. Thus, after just three years of slight drought, a clear trend towards an accumulation of P in the soil and towards a decrease of P in the stand biomass was observed. The P accumulation in the soil in the drought plots was mainly in forms that were not directly available to plants. These indirect effects of drought including the decrease in plant P availability, may
Keywords: climate change; Drought; Mediterranean ecosystems; mineralomasses; nutrient concentrations; nutrient cycles; phosphorus; Quercus ilex; Soil

Increasing drought decreases phosphorus availability in an evergreen Mediterranean forest - Sardans, Jordi; Penuelas, Josep (Plant and Soil, 2004)
Mediterranean ecosystems are water-limited and frequently also nutrient-limited. We aimed to investigate the effects of increasing drought, as predicted by GCM and eco-physiological models for the next decades, on the P cycle and P plant availability in a Mediterranean forest. We conducted a ﬁeld experiment in a mature evergreen oak forest, establishing four drought-treatment plots and four control plots (150 m2 each). After three years, the runoff and rainfall exclusion reduced an overall 22% the soil moisture, and the runoff exclusion alone reduced it 10%. The reduction of 22% in soil moisture produced a decrease of 40% of the accumulated aboveground plant P content, above all because there was a smaller increase in aerial biomass. The plant leaf P content increased by 100 ± 40 mg m−2 in the control plots, whereas it decreased by 40 ± 40 mg m−2 in the drought plots. The soil Po-NaHCO3 (organic labile-P fraction) increased by 25% in consonance with the increase in litterfall, while the inorganic labile-P fraction decreased in relation to the organic labile-P fraction up to 48%, indicating a decrease in microbial activity. Thus, after just three years of slight drought, a clear trend towards an accumulation of P in the soil and towards a decrease of P in the stand biomass was observed. The P accumulation in the soil in the drought plots was mainly in forms that were not directly available to plants. These indirect effects of drought including the decrease in plant P availability, may
Keywords: climate change; Drought; Mediterranean ecosystems; mineralomasses; nutrient concentrations; nutrient cycles; phosphorus; Quercus ilex; Soil

Indicator taxa of spider (Araneae) diversity and their efficiency in conservation - Cardoso, Pedro; Silva, Israel; de Oliveira, Nuno G; Serrano, Artur R M (Biological Conservation, 2004)
A considerable number of alternative approaches have been suggested during the last years to predict species richness of a given taxon, while retaining information on the identities of the observed individuals. Such information can be extremely useful for choosing conservation priority areas, either by using raw richness values or, preferentially, by considering the complementarity between potential sites. Among the most popular approaches is the use of indicator taxa. Both one single family and a group of several families are here tested in their ability to predict the number of spider (Araneae) species independently of sampling eﬀort, geographical location and type of habitat. We use data from three Portuguese protected areas as a test case. A two-family indicator group – Gnaphosidae and Theridiidae – is found to be a good surrogate of species richness, even if caution is needed regarding the comparison of sites with considerably diﬀerent sampling eﬀort or vegetation cover. No single family can be seen as a good surrogate of the totality of spiders. In addition, only a group of the two mentioned families is found to be eﬃcient and reliable either when used to rank sites according to taxa richness or for determining near-minimum sets of sites for conservation. We therefore recommend surrogacy with this indicator group as a promising approach for the prediction of spider species richness or evaluation and ranking of areas according to their conservation importance. The reached conclusions should uphold for Portugal and the entire Mediterranean region.
Keywords: Complementarity; estimation; Mediterranean; Portugal; Species richness

Indicator taxa of spider (Araneae) diversity and their efficiency in conservation - Cardoso, Pedro; Silva, Israel; de Oliveira, Nuno G; Serrano, Artur R M (Biological Conservation, 2004)
A considerable number of alternative approaches have been suggested during the last years to predict species richness of a given taxon, while retaining information on the identities of the observed individuals. Such information can be extremely useful for choosing conservation priority areas, either by using raw richness values or, preferentially, by considering the complementarity between potential sites. Among the most popular approaches is the use of indicator taxa. Both one single family and a group of several families are here tested in their ability to predict the number of spider (Araneae) species independently of sampling eﬀort, geographical location and type of habitat. We use data from three Portuguese protected areas as a test case. A two-family indicator group – Gnaphosidae and Theridiidae – is found to be a good surrogate of species richness, even if caution is needed regarding the comparison of sites with considerably diﬀerent sampling eﬀort or vegetation cover. No single family can be seen as a good surrogate of the totality of spiders. In addition, only a group of the two mentioned families is found to be eﬃcient and reliable either when used to rank sites according to taxa richness or for determining near-minimum sets of sites for conservation. We therefore recommend surrogacy with this indicator group as a promising approach for the prediction of spider species richness or evaluation and ranking of areas according to their conservation importance. The reached conclusions should uphold for Portugal and the entire Mediterranean region.
Keywords: Complementarity; estimation; Mediterranean; Portugal; Species richness

Indicator taxa of spider (Araneae) diversity and their efficiency in conservation - Cardoso, Pedro; Silva, Israel; de Oliveira, Nuno G.; Serrano, Artur R. M. (Biological Conservation, 2004)
A considerable number of alternative approaches have been suggested during the last years to predict species richness of a given taxon, while retaining information on the identities of the observed individuals. Such information can be extremely useful for choosing conservation priority areas, either by using raw richness values or, preferentially, by considering the complementarity between potential sites. Among the most popular approaches is the use of indicator taxa. Both one single family and a group of several families are here tested in their ability to predict the number of spider (Araneae) species independently of sampling eﬀort, geographical location and type of habitat. We use data from three Portuguese protected areas as a test case. A two-family indicator group – Gnaphosidae and Theridiidae – is found to be a good surrogate of species richness, even if caution is needed regarding the comparison of sites with considerably diﬀerent sampling eﬀort or vegetation cover. No single family can be seen as a good surrogate of the totality of spiders. In addition, only a group of the two mentioned families is found to be eﬃcient and reliable either when used to rank sites according to taxa richness or for determining near-minimum sets of sites for conservation. We therefore recommend surrogacy with this indicator group as a promising approach for the prediction of spider species richness or evaluation and ranking of areas according to their conservation importance. The reached conclusions should uphold for Portugal and the entire Mediterranean region.
Keywords: Complementarity; estimation; Mediterranean; Portugal; Species richness

An interdisciplinary approach for integrating landscape management in the Common Agricultural Policy: Application to the municipality of Mertola, Southern Alentejo, Portugal - Oliveira, R; Pinto-Correia, T (ROLE OF BIODIVERSITY CONSERVATION IN THE TRANSITION TO RURAL SUSTAINABILITY, 2004)
This paper seeks to present the methodological approach of a case-study at a local scale, in the south of Portugal, where the European Union Common Agricultural Policy (CAP) has significant impacts in terms of environment, socioeconomic and landscape aspects. The municipality of Mertola is located in the south-eastern part of the Alentejo Region, in a marginal area in relation to socio-economic parameters and agricultural production. As in the region as a whole, the dominant land use system is the Montado in a diversified pattern, which has in the last decades been subject. to successive significant changes, raising questions as to future landscape quality, identity and the required management. As in other European rural areas, the transformations in agriculture and the productive function resulted in changes in the landscape, which have impacts also on other functions such as conservation, environment balance, recreation, life support and preservation of cultural identity. These other functions attract each day more attention as a possible set of alternatives uses in marginal areas of Europe, such as Mertola. This actual context requires thus a landscape management based on integrated policies for the rural world, following the new perspectives of the CAP but also based on a deep knowledge of local landscape dynamics and requirements for preservation of identity. This project intends to evaluate and understand: (a) the changes that have occurred in the municipality in the last decades; and (b) how they have affected landscape pattern and also people's perception and connections to this landscape identity. The intent is to build up proposals for a more integrated and locally adapted formulation of CAP objectives and instruments. This paper will present the changes in landscape pattern and character registered in the study area for the last decades, the interdisciplinary methodology adopted, as well as the results of the first phase of the project.

An interdisciplinary approach for integrating landscape management in the Common Agricultural Policy: Application to the municipality of Mertola, Southern Alentejo, Portugal - Oliveira, R.; Pinto-Correia, T. (ROLE OF BIODIVERSITY CONSERVATION IN THE TRANSITION TO RURAL SUSTAINABILITY, 2004)
This paper seeks to present the methodological approach of a case-studyat a local scale, in the south of Portugal, where the European Union Common Agricultural Policy (CAP) has significant impacts in terms of environment, socioeconomic and landscape aspects. The municipality of Mertola is located in the south-eastern part of the Alentejo Region, in a marginal area in relation to socio-economic parameters and agricultural production. As in the region as a whole, the dominant land use system is the Montado in a diversified pattern, which has in the last decades been subject. to successive significant changes, raising questions as to future landscape quality, identity and the required management. As in other European rural areas, the transformations in agriculture and the productive function resulted in changes in the landscape, which have impacts also on other functions such as conservation, environment balance, recreation, life support and preservation of cultural identity. These other functions attract each day more attention as a possible set of alternatives uses in marginal areas of Europe, such as Mertola. This actual context requires thus a landscape management based on integrated policies for the rural world, following the new perspectives of the CAP but also based on a deep knowledge of local landscape dynamics and requirements for preservation of identity. This project intends to evaluate and understand: (a) the changes that have occurred in the municipality in the last decades; and (b) how they have affected landscape pattern and also people's perception and connections to this landscape identity. The intent is to build up proposals for a more integrated and locally adapted formulation of CAP objectives and instruments. This paper will present the changes in landscape pattern and character registered in the study area for the last decades, the interdisciplinary methodology adopted, as well as the results of the first phase of the project.
The following values have no corresponding Zotero field: periodical: ROLE OF BIODIVERSITY CONSERVATION IN THE TRANSITION TO RURAL SUSTAINABILITY pub-location: NIEUWE HEMWEG 6B, 1013 BG AMSTERDAM, NETHERLANDS

Invasión del matorral por Genista hystrix en una dehesa salmantina (España) - Caro Domínguez, Francisco; Sánchez Anta, María Ángeles; Tarazona Lafarga, Teresa (Ecología Aplicada, 2004)
The invasion of Genisto hystricis-Cytisetum multiflori shrubs in a Salamancan "dehesa" (Quercus forest with low density), was studied using permanent quadrat and transect methodology. The results indicate that, of all shrub species, Genista hystrix Lge. is the predominant invading species in this sclerophyllous formation, due to its growth rate and phenomorphology. The overall invasion rate of this shrub in the "dehesa" has been calculated to be approximately 2.26 m 2 per year
Keywords: "dehesa"; Cytisus multiflorus (L'Hèr.) Sweet.; Cytisus scoparius (L.) Link; dynamics; Genista hystrix Lge.; Invasive species; Quercus rotundifolia Lam.; Salamanca; sclerophyllous; Shrubs

Invasión del matorral por Genista hystrix en una dehesa salmantina (España) - Caro Domínguez, Francisco; Sánchez Anta, María Ángeles; Tarazona Lafarga, Teresa (Ecología Aplicada, 2004)
The invasion of Genisto hystricis-Cytisetum multiflori shrubs in a Salamancan "dehesa" (Quercus forest with low density), was studied using permanent quadrat and transect methodology. The results indicate that, of all shrub species, Genista hystrix Lge. is the predominant invading species in this sclerophyllous formation, due to its growth rate and phenomorphology. The overall invasion rate of this shrub in the "dehesa" has been calculated to be approximately 2.26 m 2 per year
Keywords: "dehesa"; Cytisus multiflorus (L'Hèr.) Sweet.; Cytisus scoparius (L.) Link; dynamics; Genista hystrix Lge.; Invasive species; Quercus rotundifolia Lam.; Salamanca; sclerophyllous; Shrubs

Isoprenoid emissions of Quercus spp. (Q. suber and Q. ilex) in mixed stands contrasting in interspecific genetic introgression - Staudt, Michael; Mir, Celine; Joffre, Richard; Rambal, Serge; Bonin, Aurelie; Landais, Damien; Lumaret, Roselyne (New Phytologist, 2004)
• Among oak species, Quercus ilex is classiﬁed as a monoterpene emitter and Q. suber is mainly known as a nonisoprenoid emitter. The extent and origin of this diversiﬁcation is unknown. • We examined intra- and interspeciﬁc emission variability in two mixed stands which differed in their level of hybridization and reciprocal genetic introgression based on variations in cytoplasmic (chloroplast DNA) and nuclear (allozyme) markers. • At both sites all trees identiﬁed as Q. ilex, or as recent descendants from Q. ilex × Q. suber hybrids, emitted monoterpenes. Of Q. suber trees (genetically introgressed or not by Q. ilex), 91% were also monoterpene emitters, and the remainder nonemitters. One tree identiﬁed as a Q. canariensis × Q. ilex hybrid emitted both isoprene and monoterpenes. Compared with Q. ilex, the standard emission rate of Q. suber was higher in summer and lower in autumn. Both species emitted the same monoterpenes, proportions of which showed signiﬁcant intra- and interspeciﬁc variability. • The results suggest that Q. suber populations in the French Mediterranean intrinsically emit monoterpenes, and that gene ﬂow between oak species contributes to diversiﬁcation of emission signatures.
Keywords: basal emission rate; chemotaxonomy; chemotypes; Evergreen oaks; genetic introgression; isoprene; Monoterpenes; VOC (volatile organic compound) emissions.

Isoprenoid emissions of Quercus spp. (Q. suber and Q. ilex) in mixed stands contrasting in interspecific genetic introgression - Staudt, Michael; Mir, Celine; Joffre, Richard; Rambal, Serge; Bonin, Aurelie; Landais, Damien; Lumaret, Roselyne (New Phytologist, 2004)
• Among oak species, Quercus ilex is classiﬁed as a monoterpene emitter and Q. suber is mainly known as a nonisoprenoid emitter. The extent and origin of this diversiﬁcation is unknown. • We examined intra- and interspeciﬁc emission variability in two mixed stands which differed in their level of hybridization and reciprocal genetic introgression based on variations in cytoplasmic (chloroplast DNA) and nuclear (allozyme) markers. • At both sites all trees identiﬁed as Q. ilex, or as recent descendants from Q. ilex × Q. suber hybrids, emitted monoterpenes. Of Q. suber trees (genetically introgressed or not by Q. ilex), 91% were also monoterpene emitters, and the remainder nonemitters. One tree identiﬁed as a Q. canariensis × Q. ilex hybrid emitted both isoprene and monoterpenes. Compared with Q. ilex, the standard emission rate of Q. suber was higher in summer and lower in autumn. Both species emitted the same monoterpenes, proportions of which showed signiﬁcant intra- and interspeciﬁc variability. • The results suggest that Q. suber populations in the French Mediterranean intrinsically emit monoterpenes, and that gene ﬂow between oak species contributes to diversiﬁcation of emission signatures.
Keywords: basal emission rate; chemotaxonomy; chemotypes; Evergreen oaks; genetic introgression; isoprene; Monoterpenes; VOC (volatile organic compound) emissions.

La diversitá cloroplastica delle querce italiane: evidenze di una maggiore ricchezza genetica nelle popolazioni meridionali e insulari - Fineschi, S.; Vendramin, G. G. (iForest - Biogeosciences and Forestry, 2004)
Results of the analysis of non-coding regions of the chloroplast genome in Italian population of deciduous oaks (subgenus Quercus) and holm oak (subgenus Scleropyllodris) are reported. Deciduous oak revealed the occurrence of six chloroplast haplotypes, differently distributed in the single geographic areas (northern, central, and southern Italy, and major islands). Moreover, most of the present Italian oak populations seems to derive from two major refugia, located in Sicily and in the Balkans, respectively. The most likely migration dynamics from the refugia towards the central and northern part of the peninsula are discussed. Migration pathways resulted to have been different in the various geographic areas. The presence of an endemic haplotype in Sardinia and Corsica was considered of particular interest. In Italian holm oak populations eight haplotypes were detected, six of them in Sicily. Five out of six Sicilian haplotypes resulted to be endemic. The Italian peninsula was colonized by two major haplotypes, one of them originating from Sicily. Results on deciduous oaks and holm oak in Italy highlight the important role played by the populations from the south and from the major islands in the colonization the Italian peninsula after the last ice age.
The following values have no corresponding Zotero field: pub-location: (1) CNR Istituto per la Protezione delle Piante, via Madonna del Piano, Edificio E, 50019 Sesto Fiorentino, Firenze; (2) CNR Istituto di Genetica Vegetale, sezione di Firenze, via Madonna del Piano, Edificio D, 50019 Sesto Fiorentino, Firenze publisher: SISEF - Italian Society of Silviculture and Forest Ecology
Keywords: Chloroplastic Diversity; colonization; conservation; glacial refugia; phylogeography; Quercus

La diversitá cloroplastica delle querce italiane: evidenze di una maggiore ricchezza genetica nelle popolazioni meridionali e insulari - Fineschi, S; Vendramin, G G (iForest - Biogeosciences and Forestry, 2004)
Results of the analysis of non-coding regions of the chloroplast genome in Italian population of deciduous oaks (subgenus Quercus) and holm oak (subgenus Scleropyllodris) are reported. Deciduous oak revealed the occurrence of six chloroplast haplotypes, differently distributed in the single geographic areas (northern, central, and southern Italy, and major islands). Moreover, most of the present Italian oak populations seems to derive from two major refugia, located in Sicily and in the Balkans, respectively. The most likely migration dynamics from the refugia towards the central and northern part of the peninsula are discussed. Migration pathways resulted to have been different in the various geographic areas. The presence of an endemic haplotype in Sardinia and Corsica was considered of particular interest. In Italian holm oak populations eight haplotypes were detected, six of them in Sicily. Five out of six Sicilian haplotypes resulted to be endemic. The Italian peninsula was colonized by two major haplotypes, one of them originating from Sicily. Results on deciduous oaks and holm oak in Italy highlight the important role played by the populations from the south and from the major islands in the colonization the Italian peninsula after the last ice age.
Keywords: Chloroplastic Diversity; colonization; conservation; glacial refugia; phylogeography; Quercus

Laccase and peroxidase isoenzymes during leaf litter decomposition of Quercus ilex in a Mediterranean ecosystem - Di Nardo, C.; Cinquegrana, A.; Papa, S.; Fuggi, A.; Fioretto, A. (Soil Biology and Biochemistry, 2004)
The dynamics of leaf litter decomposition of Quercus ilex (L.) were investigated over a 2 year period by determining the activities and isoenzyme distribution of laccases and peroxidases. The analysis of isoenzymes was performed by isoelectric focusing on high stability pH gradients with high resolving power. The preparation of zymograms was carried out using the leaf litter extract without previous concentration. During litter decomposition, laccase and peroxidase activities changed as well as the type and number of enzyme isoforms. The activities of both enzymes were low (%0.017 and %0.031 mmol o-tolidine oxidized hK1 gK1 d.w. for laccase and peroxidase, respectively) in ﬁrst year and increased in October–January of the second year of litter decay. The highest activities measured after 15–18 months of litter exposure (0.37G0.03 and 0.19G0.02 mmol o-tolidine oxidized hK1 gK1 d.w. for laccase and peroxidase, respectively), showed that litter chemical composition affected the growth of ligninolytic microbial community. The activation energy for laccase and peroxidase reactions also changed during decomposition: the highest values (55G6 kJ molK1 for laccase and 60G6 kJ molK1 for peroxidase) occurred in autumn–winter, even if spatial changes were evidenced. Some enzyme isoforms (pIZ5.3 and 5.5 for laccase and pIZ5.0 and 5.1 for peroxidase, respectively), contributed more than others to the overall laccase and peroxidase activity, suggesting that some ligninolytic species bloomed in particular seasons of the year, even if other species with similar functional activities colonized the litter.
Keywords: Enzyme activity; isoelectrofocusing; laccase; litter decomposition; peroxidase

Laccase and peroxidase isoenzymes during leaf litter decomposition of Quercus ilex in a Mediterranean ecosystem - Di Nardo, C; Cinquegrana, A; Papa, S; Fuggi, A; Fioretto, a (Soil Biology and Biochemistry, 2004)
The dynamics of leaf litter decomposition of Quercus ilex (L.) were investigated over a 2 year period by determining the activities and isoenzyme distribution of laccases and peroxidases. The analysis of isoenzymes was performed by isoelectric focusing on high stability pH gradients with high resolving power. The preparation of zymograms was carried out using the leaf litter extract without previous concentration. During litter decomposition, laccase and peroxidase activities changed as well as the type and number of enzyme isoforms. The activities of both enzymes were low (%0.017 and %0.031 mmol o-tolidine oxidized hK1 gK1 d.w. for laccase and peroxidase, respectively) in ﬁrst year and increased in October–January of the second year of litter decay. The highest activities measured after 15–18 months of litter exposure (0.37G0.03 and 0.19G0.02 mmol o-tolidine oxidized hK1 gK1 d.w. for laccase and peroxidase, respectively), showed that litter chemical composition affected the growth of ligninolytic microbial community. The activation energy for laccase and peroxidase reactions also changed during decomposition: the highest values (55G6 kJ molK1 for laccase and 60G6 kJ molK1 for peroxidase) occurred in autumn–winter, even if spatial changes were evidenced. Some enzyme isoforms (pIZ5.3 and 5.5 for laccase and pIZ5.0 and 5.1 for peroxidase, respectively), contributed more than others to the overall laccase and peroxidase activity, suggesting that some ligninolytic species bloomed in particular seasons of the year, even if other species with similar functional activities colonized the litter.
Keywords: Enzyme activity; isoelectrofocusing; laccase; litter decomposition; peroxidase

Land manager attitudes toward management, regeneration, and conservation of Spanish holm oak savannas (dehesas) - Plieninger, T; Modolell y Mainou, J; Konold, W (Landscape and Urban Planning, 2004)
Biological conservation in Spanish dehesas critically depends on the long-term persistence of a holm oak tree layer.Managers of private estates in Cáceres province, Spain, were surveyed about their conservation attitudes and behavior, especially as regards the widespread regeneration failure of oak stands. The aim was to define land-user perspectives on oak conservation in dehesas as basis for the design of suitable oak regeneration programs. Dehesa estates are managed diversely for a variety of goals, with lamb and beef production predominating. Small operations (‘minifundios’) had significantly higher stocking levels than large operations (‘latifundios’). Results suggest that managers strongly appreciate oaks, both for income- and non-income-related motivations like the preservation of real estate value or family tradition. Concern about threats to oak stands like lacking regeneration, oak decline, or conversion in urban areas varied in intensity, but most managers expected major changes for the future. Statistical relationships were established between oak appreciation and socio-economic variables like age, land ownership, years the operation had been owned by the family, and use of oak products. The survey revealed great confusion about existing oak conservation regulations. For long-term support to be assured, policy should orient its efforts toward conservation incentive schemes, environmental education, and technical assistance.
Keywords: Dehesa; Land-use; landowner motivations; Mediterranean; Quercus ilex; rangeland policy

Land manager attitudes toward management, regeneration, and conservation of Spanish holm oak savannas (dehesas) - Plieninger, T.; Modolell y Mainou, J.; Konold, W. (Landscape and Urban Planning, 2004)
Biological conservation in Spanish dehesas critically depends on the long-term persistence of a holm oak tree layer.Managers of private estates in Cáceres province, Spain, were surveyed about their conservation attitudes and behavior, especially as regards the widespread regeneration failure of oak stands. The aim was to define land-user perspectives on oak conservation in dehesas as basis for the design of suitable oak regeneration programs. Dehesa estates are managed diversely for a variety of goals, with lamb and beef production predominating. Small operations (‘minifundios’) had significantly higher stocking levels than large operations (‘latifundios’). Results suggest that managers strongly appreciate oaks, both for income- and non-income-related motivations like the preservation of real estate value or family tradition. Concern about threats to oak stands like lacking regeneration, oak decline, or conversion in urban areas varied in intensity, but most managers expected major changes for the future. Statistical relationships were established between oak appreciation and socio-economic variables like age, land ownership, years the operation had been owned by the family, and use of oak products. The survey revealed great confusion about existing oak conservation regulations. For long-term support to be assured, policy should orient its efforts toward conservation incentive schemes, environmental education, and technical assistance.
Keywords: Dehesa; Land-use; landowner motivations; Mediterranean; Quercus ilex; rangeland policy

Litter decomposition and faunal activity in Mediterranean forest soils: effects of N content and the moss layer - Garcia-Pausas, Jordi; Casals, Pere; Romanyà, Joan (Soil Biology and Biochemistry, 2004)
Accumulation of soil carbon is mainly controlled by the balance between litter production and litter decomposition. Usually In Mediterranean forests there are contrasting conditions in the distribution of faunal activity and the moss layer that may have different effects on litter decomposition. Decomposition and faunal activity were studied by exposing litter of contrasting quality (Pinus halepensis Mill. and Quercus ilex L.) for 3.5 yr in three Mediterranean pine forests of the eastern Iberian Peninsula. The effects of mosses on decomposition and on faunal activity were studied by exposing P. halepensis litter either on moss patches or directly on the forest ﬂoor. Faecal pellet production was used as an indication of faunal activity. Water availability or soil characteristics seem to limit faunal activities in the drier sites. Faecal pellets were not found during the ﬁrst stages of decomposition and in all sites they appeared when about a 30% of the initial litter had decomposed. Under wet conditions faecal pellet production was very high and a mass balance suggested that soil faunal activity may result in a net ﬂow of organic matter from the lower organic horizons to the surface Oi horizon. Mosses slightly increased mass loss of pine litter probably as a consequence of high potentially mineralizable nitrogen in the Oa horizon of moss patches and also, perhaps, as a consequence of the higher moisture content measured in the Oi horizon needles sampled among the mosses. In contrast, moss patches reduced faunal activity. The effect of litter quality on mass loss was not always signiﬁcant, suggesting an interaction between litter quality and site conditions. During the ﬁrst stages of decomposition there was N immobilisation in P. halepensis litter (poorer in N) and N release from Q. ilex litter (richer in N). In conclusion, in these forests soil microclimate and/or N availability appear to be more important controlling litter decomposition than the distribution of faunal activity.
Keywords: faecal pellets; litter decomposition; litter n content; Mediterranean forests; moss layer; nitrogen dynamics

Litter decomposition and faunal activity in Mediterranean forest soils: effects of N content and the moss layer - Garcia-Pausas, Jordi; Casals, Pere; Romanyà, Joan (Soil Biology and Biochemistry, 2004)
Accumulation of soil carbon is mainly controlled by the balance between litter production and litter decomposition. Usually In Mediterranean forests there are contrasting conditions in the distribution of faunal activity and the moss layer that may have different effects on litter decomposition. Decomposition and faunal activity were studied by exposing litter of contrasting quality (Pinus halepensis Mill. and Quercus ilex L.) for 3.5 yr in three Mediterranean pine forests of the eastern Iberian Peninsula. The effects of mosses on decomposition and on faunal activity were studied by exposing P. halepensis litter either on moss patches or directly on the forest ﬂoor. Faecal pellet production was used as an indication of faunal activity. Water availability or soil characteristics seem to limit faunal activities in the drier sites. Faecal pellets were not found during the ﬁrst stages of decomposition and in all sites they appeared when about a 30% of the initial litter had decomposed. Under wet conditions faecal pellet production was very high and a mass balance suggested that soil faunal activity may result in a net ﬂow of organic matter from the lower organic horizons to the surface Oi horizon. Mosses slightly increased mass loss of pine litter probably as a consequence of high potentially mineralizable nitrogen in the Oa horizon of moss patches and also, perhaps, as a consequence of the higher moisture content measured in the Oi horizon needles sampled among the mosses. In contrast, moss patches reduced faunal activity. The effect of litter quality on mass loss was not always signiﬁcant, suggesting an interaction between litter quality and site conditions. During the ﬁrst stages of decomposition there was N immobilisation in P. halepensis litter (poorer in N) and N release from Q. ilex litter (richer in N). In conclusion, in these forests soil microclimate and/or N availability appear to be more important controlling litter decomposition than the distribution of faunal activity.
Keywords: faecal pellets; litter decomposition; litter n content; Mediterranean forests; moss layer; nitrogen dynamics

Madonna dell'Arma (San Remo, Italie) : expression locale de la végétation ligure au cours du Paléolithique moyen - Kaniewski, David; Renault-Miskovsky, Josette; de Lumley, Henry (Geobios, 2004)
Pollen analysis of Madonna dell’Arma cave inside part (Liguria, Italy) allowed us to reconstitute, at local scale, the Ligurian coastal vegetation between the end of the last interglacial period and the beginning of the pleniglacial. This transition period shows an important representation of arboreal cover and a persistence of thermophilous elements that allowed us to considerate the western Liguria as a periglacial refuge. During the end of the last interglacial, xerophytic, halophytic herbs and shrubs taken over from a Mediterranean pre-forest unit in the ﬁrst slopes constituted the coastal zone. The nearness ofArgentina torrent and theArmea inﬂuenced, in the coast, the existence of marshy zones colonized by hygrophilous trees. In the Ligurian lowlands spread out sclerophyllous and mesophilous forests according to altitude. The beginning of the pleniglacial is indicated in the sequence by increases of Pinus, Cupressaceae and Artemisia in the context of a decline in the thermophilous components. This picture of vegetation has become integrated into the multidisciplinary studies of the site and contributed to the elaboration of palaeoclimatic hypothesis similar as those revealed by the fauna.
Keywords: Interglacial; Liguria; Middle Palaeolithic; palynology; Pleniglacial; Prehistory; Upper Pleistocene

MEDIÇÃO DA EVAPOTRANSPIRAÇÃO EM COBERTOS DESCONTÍNUOS: MONTADO DE SOBRO NA REGIÃO DE LISBOA Mª Isabel F. R. FERREIRA - Ferreira, Mª Isabel F. R.; Silva, Rodolfo M.; Paço, Teresa A. (7º Congresso da Água, Lisboa, 2004)
A quantificação do uso da água pelos cobertos lenhosos está em geral mal documentada. Em Portugal este aspecto não é irrelevante já que cerca de 2/3 da superfície agrícola útil corresponde a este tipo de cobertos (pomares, florestas, vinhas, vegetação natural,...). Em cobertos regados, a evapotranspiração (ET) segue genericamente a tendência da evapotranspiração de referência (ETo). Porém, em cobertos não regados, em condições de secura estival, essa relativa proporcionalidade deixa de existir. Nessas circunstâncias, e face à escassez actual de modelos adequados, a resolução da incerteza relativamente aos consumos pressupõe a medição directa da ET ou das suas componentes. Aplicou-se o método micrometeorológico das flutuações instantâneas ou correlações turbulentas (eddy covariance) num vasto montado com utilização silvo-pastoril, relativamente denso, no vale do Tejo (entre Montijo e Palmela). Para a estimativa da transpiração (T) foi usado um método térmico de medição do fluxo de seiva. Os resultados apresentados são de 2002 e 2003, para o fluxo de seiva e 2003 para a ET. As observações complementares permitiram testar a qualidade das medições dos fluxos atmosféricos. Dos resultados da medição da ET pelo método EC (Maio a Setembro de 2003), pode constatarse que, apesar das condições atmosféricas para a evaporação serem mais favoráveis no Verão que na Primavera, houve um decréscimo de ET de cerca de 4 mm/dia em Maio (50% da energia disponível), para cerca de 2 mm/dia em Junho e, finalmente, para cerca de 1 mm/dia, em início de Agosto e em fim de Setembro (15 a 20% da energia disponível).
The following values have no corresponding Zotero field: periodical: 7º Congresso da Água, Lisboa
Keywords: água; Evapotranspiração; Fluxo de seiva; Quercus suber; Tejo

MEDIÇÃO DA EVAPOTRANSPIRAÇÃO EM COBERTOS DESCONTÍNUOS: MONTADO DE SOBRO NA REGIÃO DE LISBOA Mª Isabel F. R. FERREIRA - Ferreira, Mª Isabel F R; Silva, Rodolfo M; Paço, Teresa A (7º Congresso da Água, Lisboa, 2004)
A quantificação do uso da água pelos cobertos lenhosos está em geral mal documentada. Em Portugal este aspecto não é irrelevante já que cerca de 2/3 da superfície agrícola útil corresponde a este tipo de cobertos (pomares, florestas, vinhas, vegetação natural,...). Em cobertos regados, a evapotranspiração (ET) segue genericamente a tendência da evapotranspiração de referência (ETo). Porém, em cobertos não regados, em condições de secura estival, essa relativa proporcionalidade deixa de existir. Nessas circunstâncias, e face à escassez actual de modelos adequados, a resolução da incerteza relativamente aos consumos pressupõe a medição directa da ET ou das suas componentes. Aplicou-se o método micrometeorológico das flutuações instantâneas ou correlações turbulentas (eddy covariance) num vasto montado com utilização silvo-pastoril, relativamente denso, no vale do Tejo (entre Montijo e Palmela). Para a estimativa da transpiração (T) foi usado um método térmico de medição do fluxo de seiva. Os resultados apresentados são de 2002 e 2003, para o fluxo de seiva e 2003 para a ET. As observações complementares permitiram testar a qualidade das medições dos fluxos atmosféricos. Dos resultados da medição da ET pelo método EC (Maio a Setembro de 2003), pode constatarse que, apesar das condições atmosféricas para a evaporação serem mais favoráveis no Verão que na Primavera, houve um decréscimo de ET de cerca de 4 mm/dia em Maio (50% da energia disponível), para cerca de 2 mm/dia em Junho e, finalmente, para cerca de 1 mm/dia, em início de Agosto e em fim de Setembro (15 a 20% da energia disponível).
Keywords: água; Evapotranspiração; Fluxo de seiva; Quercus suber; Tejo

Micropropagation du Chêne-liège (Quercus suber L.) par culture d'apex issus d'axes embryonnaires - El Kbiach, Mohamed L'bachir; Lamarti, Ahmed; Abdali, Abdeslam; Badoc, Alain (Acta Botanica Gallica, 2004)
Abstract To improve the in vitro germination and development of cork oak embryonic axes, several mineral media were tested; Durzan medium modified 1/2 supplemented with 400 mg/l glutamine and 3% sucrose gave the best results. The action of BA alone or combined with other growth regulators was also studied. A low concentration (0.44 ?M) was found to give an acceptable percentage of plantlets. When combined with NAA, callogenesis was observed. The transfer of cultures in conditions of low luminosity led to the formation of several axillary buds. These buds were multiplied on a solid medium supplemented with GA3 at low concentration. The buds were elongated, then rooted on a growth regulator-free medium after brief dipping in an auxinic solution. The rooted plants were potted on horticultural substrate.
doi: 10.1080/12538078.2004.10515443doi: 10.1080/12538078.2004.10515443The following values have no corresponding Zotero field: publisher: Taylor & Francis
Keywords: Cork oak; embryonic axis; in vitro culture; organogenesis; Quercus suber

Micropropagation du Chêne-liège (Quercus suber L.) par culture d'apex issus d'axes embryonnaires - El Kbiach, Mohamed L'bachir; Lamarti, Ahmed; Abdali, Abdeslam; Badoc, Alain (Acta Botanica Gallica, 2004)
Abstract To improve the in vitro germination and development of cork oak embryonic axes, several mineral media were tested; Durzan medium modified 1/2 supplemented with 400 mg/l glutamine and 3% sucrose gave the best results. The action of BA alone or combined with other growth regulators was also studied. A low concentration (0.44 ?M) was found to give an acceptable percentage of plantlets. When combined with NAA, callogenesis was observed. The transfer of cultures in conditions of low luminosity led to the formation of several axillary buds. These buds were multiplied on a solid medium supplemented with GA3 at low concentration. The buds were elongated, then rooted on a growth regulator-free medium after brief dipping in an auxinic solution. The rooted plants were potted on horticultural substrate.
doi: 10.1080/12538078.2004.10515443
Keywords: Cork oak; embryonic axis; in vitro culture; organogenesis; Quercus suber

Micropropagation of cork oak (Quercus suber L.) by apical bud culture from embryonic axes - El Kbiach, M L; Lamarti, A; Abdali, A; Badoc, A (ACTA BOTANICA GALLICA, 2004)
To improve the in vitro germination and development of cork Oak embryonic axes, several mineral media were tested; Durzan medium modified 1/2 supplemented with 400 mg/l glutamine and 3% sucrose gave the best results. The action of BA alone or combined with other growth regulators was also studied. A low concentration (0.44 mu M) was found to give an acceptable percentage of plantlets. When combined with NAA, callogenesis was observed. The transfer of cultures in conditions of low luminosity led to the formation of several axillary buds. These buds were multiplied on a solid medium supplemented with GA(3) at low concentration. The buds were elongated, then rooted on a growth regulator-free medium after brief dipping in an auxinic solution. The rooted plants were potted on horticultural substrate.
Keywords: Cork oak; embryon; in vitro culture; Quercus suber

Micropropagation of cork oak (Quercus suber L.) by apical bud culture from embryonic axes - El Kbiach, M. L.; Lamarti, A.; Abdali, A.; Badoc, A. (ACTA BOTANICA GALLICA, 2004)
To improve the in vitro germination and development of cork Oakembryonic axes, several mineral media were tested; Durzan medium modified 1/2 supplemented with 400 mg/l glutamine and 3% sucrose gave the best results. The action of BA alone or combined with other growth regulators was also studied. A low concentration (0.44 mu M) was found to give an acceptable percentage of plantlets. When combined with NAA, callogenesis was observed. The transfer of cultures in conditions of low luminosity led to the formation of several axillary buds. These buds were multiplied on a solid medium supplemented with GA(3) at low concentration. The buds were elongated, then rooted on a growth regulator-free medium after brief dipping in an auxinic solution. The rooted plants were potted on horticultural substrate.
The following values have no corresponding Zotero field: pub-location: FACULTE DE PHARMACIE, BP 83, F-59006 LILLE-CEDEX, FRANCE publisher: SOC BOTANIQUE FRANCE
Keywords: cork oak; Quercus suber; in vitro culture; embryon

Micropropagation of cork oak (Quercus suber L.) by axillary buds - El Kbiach, M L; Lamarti, A; Abdali, A; Badoc, A (ACTA BOTANICA GALLICA, 2004)
The in vitro regeneration from cork oak axillary buds was investigated. Different macronutrient formulas supplemented with MS micronutrients, vitamins and 3% sucrose were tested on shoot multiplication and rooting phases. The WPM macronutrients improved caulogenesis and shoot multiplication. Rooting was achieved on WPM 1/2 macronutrients. Dipping the base of the shoots in an IBA concentrated solution improved the rooting phase. 92% of the rooted plants were successfully potted on horticultural substrate with a high relative humidity.
Keywords: browning; contaminants; Cork oak; micropropagation; phenolic compounds; Quercus suber L.; tissue culture

Micropropagation of cork oak (Quercus suber L.) by axillary buds - El Kbiach, M. L.; Lamarti, A.; Abdali, A.; Badoc, A. (ACTA BOTANICA GALLICA, 2004)
The in vitro regeneration from cork oak axillary buds was investigated. Different macronutrient formulas supplemented with MS micronutrients, vitamins and 3% sucrose were tested on shoot multiplication and rooting phases. The WPM macronutrients improved caulogenesis and shoot multiplication. Rooting was achieved on WPM 1/2 macronutrients. Dipping the base of the shoots in an IBA concentrated solution improved the rooting phase. 92% of the rooted plants were successfully potted on horticultural substrate with a high relative humidity.
The following values have no corresponding Zotero field: pub-location: FACULTE DE PHARMACIE, BP 83, F-59006 LILLE-CEDEX, FRANCE publisher: SOC BOTANIQUE FRANCE
Keywords: browning; contaminants; Cork oak; micropropagation; phenolic compounds; Quercus suber L.; tissue culture

Modificación del microclima edáfico producido por riegos en forestaciones de zonas semiáridas - Jiménez, M N; Ripoll, M A; Navarro, F B (Investigación agraria. Sistemas y recursos forestales, 2004)
In this work, we analyse the effect that the irrigation carried out in different times during the summer drought produces on the edaphic microclimate over holm oak plants (Quercus rotundifolia) in abandoned agricultural soils of continental semiarid climate. The study has been done over 5 plots of 60 plants each, located in the high plateaux of Rambla Becerra (Guadix-Granada), in which it has been accomplished a continuation of the survival rate and development after the planting during two years (2001-2002). The answer of the plant to its new medium was excellent in all the irrigated plots, whereas in the witness plot (without irrigation) the survival is considerably inferior. The height of the holm oaks in those plots with any kind of irrigation is significantly superior than the ones in the witness plot, and the diameter of the holm oaks of the plots which receive continuous summer irrigation shows significant differences with respect to the rest of the plots. The bioclimatic diagrams achieved in each plot reflect relevant differences; the summer irrigation reaches to reduce the drought period and even, in the plot that receives the continuous summer irrigation, this is eradicated, thus generating a new period of vegetation activity. The humidity of the soil shows significant differences, being the plot number 8, which is continually being irrigated, the only one that keeps the humidity in depth. The hydric deficit diminishes punctually in the plots irrigated only once, whereas in the parcel n. 8 diminishes drastically with the following increase in the vegetation activity.
Keywords: agricultural; bioclimatic diagrams; humidity; microclimate; Soil

Modificación del microclima edáfico producido por riegos en forestaciones de zonas semiáridas - Jiménez, M. N.; Ripoll, M. A.; Navarro, F. B. (Investigación agraria. Sistemas y recursos forestales, 2004)
In this work, we analyse the effect that the irrigation carried out in different times during the summer drought produces on the edaphic microclimate over holm oak plants (Quercus rotundifolia) in abandoned agricultural soils of continental semiarid climate. The study has been done over 5 plots of 60 plants each, located in the high plateaux of Rambla Becerra (Guadix-Granada), in which it has been accomplished a continuation of the survival rate and development after the planting during two years (2001-2002). The answer of the plant to its new medium was excellent in all the irrigated plots, whereas in the witness plot (without irrigation) the survival is considerably inferior. The height of the holm oaks in those plots with any kind of irrigation is significantly superior than the ones in the witness plot, and the diameter of the holm oaks of the plots which receive continuous summer irrigation shows significant differences with respect to the rest of the plots. The bioclimatic diagrams achieved in each plot reflect relevant differences; the summer irrigation reaches to reduce the drought period and even, in the plot that receives the continuous summer irrigation, this is eradicated, thus generating a new period of vegetation activity. The humidity of the soil shows significant differences, being the plot number 8, which is continually being irrigated, the only one that keeps the humidity in depth. The hydric deficit diminishes punctually in the plots irrigated only once, whereas in the parcel n. 8 diminishes drastically with the following increase in the vegetation activity.
Keywords: agricultural; bioclimatic diagrams; humidity; microclimate; Soil

Multifunctionality in Mediterranean landscapes–past and future - Pinto-Correia, T.; Vos, Willem (The New Dimensions of the European Landscapes, 2004)
During past decades many of the traditional multifunctional Mediterranean landscapes with their typical complexes of agro-, silvo- and pastoral components changed thoroughly. Nowadays only few of them are still vital. Their complex farming systems secure at the same time a multitude of other functions than just agricultural production, such as support for recreation, amenity, cultural identity, preservation of natural resources and environmental quality. Some of these unique, old Mediterranean landscapes are discussed. They cover a broad range from near-tonature high mountain landscapes and terraced small-scale submediterranean polyculture landscapes to dry Mediterranean agro-silvo-pastoral landscapes. All these are changing, either spontaneously due to changing socio-economic and cultural conditions, or as a result of conscious policies, with the Common Agricultural Policy as a main driver. Even measures created to support specific traditional land uses and their landscapes are often not successful as they focus on only a part of the system. These policies and measures will not hold the valuable traditional systems from collapsing and subsequent vanishing. Some other policy instruments, such as those in forestry, are not meant to support them, but to transform them in favour of new monofunctionality. New strategies and instruments ought to deal with these multifunctional landscapes in a more integrated way, if some of them are to be maintained or transformed into others with similar qualities.
The following values have no corresponding Zotero field: periodical: The New Dimensions of the European Landscapes
Keywords: agri-environmental; agro-silvo-pastoral; CAP; landscape; Mediterranean; multifunctionality

Multifunctionality in Mediterranean landscapes–past and future - Pinto-Correia, T; Vos, Willem (The New Dimensions of the European Landscapes, 2004)
During past decades many of the traditional multifunctional Mediterranean landscapes with their typical complexes of agro-, silvo- and pastoral components changed thoroughly. Nowadays only few of them are still vital. Their complex farming systems secure at the same time a multitude of other functions than just agricultural production, such as support for recreation, amenity, cultural identity, preservation of natural resources and environmental quality. Some of these unique, old Mediterranean landscapes are discussed. They cover a broad range from near-tonature high mountain landscapes and terraced small-scale submediterranean polyculture landscapes to dry Mediterranean agro-silvo-pastoral landscapes. All these are changing, either spontaneously due to changing socio-economic and cultural conditions, or as a result of conscious policies, with the Common Agricultural Policy as a main driver. Even measures created to support specific traditional land uses and their landscapes are often not successful as they focus on only a part of the system. These policies and measures will not hold the valuable traditional systems from collapsing and subsequent vanishing. Some other policy instruments, such as those in forestry, are not meant to support them, but to transform them in favour of new monofunctionality. New strategies and instruments ought to deal with these multifunctional landscapes in a more integrated way, if some of them are to be maintained or transformed into others with similar qualities.
Keywords: agri-environmental; agro-silvo-pastoral; CAP; landscape; Mediterranean; multifunctionality

A myco-ecological analysis (lignicolous Aphyllophorales sensu lato, Basidiomycota) of the Abies pinsapo, Quercus and Pinus forests of Andalusia (southern Spain) - Ortega, a.; Navarro, F B (Nova Hedwigia, 2004)
This paper presents a mycological inventory (lignicolous Aphyllophorales) of five substrates that are characteristic of Mediterranean vegetation in Andalusia: Abies pinsapo, Quercus faginea, Quercus ilex subsp. ballota, Quercus suber and Pinus sp. pl. The species richness of each substrate was determined and related to the number of vegetation series to which these tree species belong. A series of parameters were used to determine the myco-ecological relationships in the substrates, namely the level of affinity proposed by Goslee, the level of similarity (Sørensen’s quantitative index) and the level of diversity (degree of alpha diversity). A correspondence analysis was also carried out.
Keywords: affinity.; Mediterranean forests; myco-diversity; similarity

Nest-site selection and nesting success of Little Owls (Athene noctua) in Mediterranean woodland and open habitats - Tome, R.; Bloise, C.; Korpimaki, E. (JOURNAL OF RAPTOR RESEARCH, 2004)
We studied nest-site selection by Little Owls (Athene noctua) in two Mediterranean habitats, a holm oak (Quercus rotundifolia) woodland (36 nests during 1997-99) and a steppe-like area (37 nests during 1997-99), in Southern Portugal, by comparing macrohabitat and microhabitat characteristics of used nests to those of randomly-selected nest sites. In the woodland area, predator presence seemed to be the main factor that influenced nest-site selection by owls. In the steppe area, a large number of alternative cavities around a nest appeared as the most important variable associated with nest-site selection. At this site, size of stones in stone piles also seemed to influence nest-site selection; owls nested in piles with larger than average stones. We also found tree girth was positively associated with nesting Success ill the woodland area. Larger trees held more complex cavities that may have improved the ability of adults and offspring in escaping from predators. Other variables, Such as distance to human habitations and the orientation of nest-site entrance might have influenced nesting success as well. Predation risk and the internal features of nest cavities were the most likely factors affecting nest-site selection and nesting success of Little Owls in Mediterranean habitats.
The following values have no corresponding Zotero field: pub-location: 14377 117TH STREET SOUTH, HASTINGS, MN 55033 USA publisher: RAPTOR RESEARCH FOUNDATION INC
Keywords: Athene noctua; habitat selection; Little Owl; Mediterranean Region; predation risk; reproductive success

Nest-site selection and nesting success of Little Owls (Athene noctua) in Mediterranean woodland and open habitats - Tome, R; Bloise, C; Korpimaki, E (JOURNAL OF RAPTOR RESEARCH, 2004)
We studied nest-site selection by Little Owls (Athene noctua) in two Mediterranean habitats, a holm oak (Quercus rotundifolia) woodland (36 nests during 1997-99) and a steppe-like area (37 nests during 1997-99), in Southern Portugal, by comparing macrohabitat and microhabitat characteristics of used nests to those of randomly-selected nest sites. In the woodland area, predator presence seemed to be the main factor that influenced nest-site selection by owls. In the steppe area, a large number of alternative cavities around a nest appeared as the most important variable associated with nest-site selection. At this site, size of stones in stone piles also seemed to influence nest-site selection; owls nested in piles with larger than average stones. We also found tree girth was positively associated with nesting Success ill the woodland area. Larger trees held more complex cavities that may have improved the ability of adults and offspring in escaping from predators. Other variables, Such as distance to human habitations and the orientation of nest-site entrance might have influenced nesting success as well. Predation risk and the internal features of nest cavities were the most likely factors affecting nest-site selection and nesting success of Little Owls in Mediterranean habitats.
Keywords: Athene noctua; habitat selection; Little Owl; Mediterranean Region; predation risk; reproductive success

A new species of Pseudosinella from Portugal (Insecta : Collembola). XVIIth contribution. - Da Gama, M M (REVUE SUISSE DE ZOOLOGIE, 2004)
Pseudosinella angelae sp. n. is described from a typical Mediterranean landscape dominated by Quercus suber L. in the surroundings of Lisbon. Morphological comparison with similar species is made, in order to establish the genealogical position of the new species.
Keywords: Collembola; Insecta; new species; Portugal; Pseudosinella

Nitrogen-use efficiency: trade-offs between N productivity and mean residence time at organ, plant and population levels - SILLA, F; Escudero, a (Functional Ecology, 2004)
* 1Nitrogen-use efficiency (NUEN) is often decomposed into the product of N productivity (AN) and the mean residence time of N (MRTN). Theory suggests a trade-off between both components, but direct experimental evidence is still scarce. A field study with young trees of the evergreen Quercus ilex and the marcescent-evergreen Quercus faginea was carried out to test this trade-off through analysis of plant traits at organ, whole-plant and population levels. * 2Specific leaf area (SLA) was the main trait positively related to AN in Q. faginea. By contrast, greater litter production and consumption by caterpillars resulted in larger N losses and shorter MRTN in Q. faginea. Early leaf senescence in Q. faginea produced leaf litter with high N concentration that contributed significantly to N loss. Moreover, Q. ilex had higher plant survivorship. The inverse relationship between leaf longevity and SLA is probably a key component of the trade-off between N losses and plant N productivity. * 3Quercus faginea had greater N uptake from soil, linked to its longer specific root length of fine roots and greater biomass allocation to underground tissues. Smaller N losses in Q. ilex compensated for its smaller N uptake and allowed a similar N balance at whole-plant level. * 4Our results support the hypothesis of a trade-off between AN and MRTN. Quercus ilex had a long MRTN, while Q. faginea has a high AN, and vice versa. The long MRTN in Q. ilex involves not only reduced N loss through long intrinsic leaf life span, but also resistance to harsh environmental factors and defence against herbivores. This suggests that a long MRTN is a potentially successful strategy in nutrient-poor environments.
Keywords: Drought stress; herbivory; nitrogen loss; nitrogen uptake; plant strategies

Nitrogen-use efficiency: trade-offs between N productivity and mean residence time at organ, plant and population levels - SILLA, F.; Escudero, A. (Functional Ecology, 2004)
* 1Nitrogen-use efficiency (NUEN) is often decomposed into the product of N productivity (AN) and the mean residence time of N (MRTN). Theory suggests a trade-off between both components, but direct experimental evidence is still scarce. A field study with young trees of the evergreen Quercus ilex and the marcescent-evergreen Quercus faginea was carried out to test this trade-off through analysis of plant traits at organ, whole-plant and population levels. * 2Specific leaf area (SLA) was the main trait positively related to AN in Q. faginea. By contrast, greater litter production and consumption by caterpillars resulted in larger N losses and shorter MRTN in Q. faginea. Early leaf senescence in Q. faginea produced leaf litter with high N concentration that contributed significantly to N loss. Moreover, Q. ilex had higher plant survivorship. The inverse relationship between leaf longevity and SLA is probably a key component of the trade-off between N losses and plant N productivity. * 3Quercus faginea had greater N uptake from soil, linked to its longer specific root length of fine roots and greater biomass allocation to underground tissues. Smaller N losses in Q. ilex compensated for its smaller N uptake and allowed a similar N balance at whole-plant level. * 4Our results support the hypothesis of a trade-off between AN and MRTN. Quercus ilex had a long MRTN, while Q. faginea has a high AN, and vice versa. The long MRTN in Q. ilex involves not only reduced N loss through long intrinsic leaf life span, but also resistance to harsh environmental factors and defence against herbivores. This suggests that a long MRTN is a potentially successful strategy in nutrient-poor environments.
The following values have no corresponding Zotero field: publisher: Blackwell Science Ltd
Keywords: Drought stress; herbivory; nitrogen loss; nitrogen uptake; plant strategies

Nursery cultivation regimes, plant functional attributes, and field performance relationships in the Mediterranean oak Quercus ilex L. - VILLAR-SALVADOR, P; Planelles, R; Enrı́quez, E; Rubira, J.Peñuelas (Forest Ecology and Management, 2004)
In this study we have addressed the effect of nitrogen fertilisation and shading used during nursery growth on the functional quality of Quercus ilex L. (holm oak) seedlings and their outplanting performance in an abandoned continental Mediterranean cropland. Three N fertilisation regimes: high and low fertilisation (154 and 34 mg N per plant, respectively) and no fertilisation, combined with two shade levels (full sun and 45% shade) were studied. Fertilisation increased the shoot size, shoot to root mass ratio (S/R), root N, and both shoot and root P concentration of the plants produced in the nursery. Fertilisation also enhanced the capacity of new root formation. Neither tissue K nor root mass was affected by N fertilisation. Shading increased S/R and root K concentration but reduced both shoot and root N concentration. Two years after planting, unfertilised seedlings had higher mortality and grew signiﬁcantly less than those cultivated at both a low and a high fertilisation level. Shading during nursery growth had no inﬂuence on the outplanting performance of holm oak seedlings. Plants with a larger shoot and higher S/R had lower mortality and grew faster than those with a smaller shoot and lower S/R. Outplanting performance of holm oak seedlings was related with root N and P concentration and with RGC. No relationship was found with either shoot nutrient concentration or root mass. We conclude that high N fertilisation of holm oak seedlings in the nursery can improve their early ﬁeld establishment in the afforestation Mediterranean abandoned croplands.
Keywords: Afforestation; Holm oak; nitrogen; nursery fertilisation; root growth capacity; shading

Nursery cultivation regimes, plant functional attributes, and field performance relationships in the Mediterranean oak Quercus ilex L. - Villar-Salvador, P.; Planelles, R.; Enrı́quez, E.; Rubira, J. Peñuelas (Forest Ecology and Management, 2004)
In this study we have addressed the effect of nitrogen fertilisation and shading used during nursery growth on the functional quality of Quercus ilex L. (holm oak) seedlings and their outplanting performance in an abandoned continental Mediterranean cropland. Three N fertilisation regimes: high and low fertilisation (154 and 34 mg N per plant, respectively) and no fertilisation, combined with two shade levels (full sun and 45% shade) were studied. Fertilisation increased the shoot size, shoot to root mass ratio (S/R), root N, and both shoot and root P concentration of the plants produced in the nursery. Fertilisation also enhanced the capacity of new root formation. Neither tissue K nor root mass was affected by N fertilisation. Shading increased S/R and root K concentration but reduced both shoot and root N concentration. Two years after planting, unfertilised seedlings had higher mortality and grew signiﬁcantly less than those cultivated at both a low and a high fertilisation level. Shading during nursery growth had no inﬂuence on the outplanting performance of holm oak seedlings. Plants with a larger shoot and higher S/R had lower mortality and grew faster than those with a smaller shoot and lower S/R. Outplanting performance of holm oak seedlings was related with root N and P concentration and with RGC. No relationship was found with either shoot nutrient concentration or root mass. We conclude that high N fertilisation of holm oak seedlings in the nursery can improve their early ﬁeld establishment in the afforestation Mediterranean abandoned croplands.
Keywords: Afforestation; Holm oak; nitrogen; nursery fertilisation; root growth capacity; shading

OAK OPEN FORESTS ('' DEHESA " OR '' MONTADO ") OF QUERCUS ROTUNDIFOLIA LAM . IN THE IBERIAN PENINSULA AND THEIR PRODUCTS - Balbuena, Enrique; Doncel, Esperanza (International Oaks, 2004)
Features dehesa, the Spanish word used to name the open forests and woodlands of Quercus species in Iberian Peninsula. Sustainability and stability in terms of ecological products; Products derived from oak open forests; Availability of products in dehesa (citation)

OAK OPEN FORESTS ('' DEHESA " OR '' MONTADO ") OF QUERCUS ROTUNDIFOLIA LAM . IN THE IBERIAN PENINSULA AND THEIR PRODUCTS - Balbuena, Enrique; Doncel, Esperanza (International Oaks, 2004)
Features dehesa, the Spanish word used to name the open forests and woodlands of Quercus species in Iberian Peninsula. Sustainability and stability in terms of ecological products; Products derived from oak open forests; Availability of products in dehesa (citation)

Ozone monitoring in a Mediterranean forest using diffusive and continuous sampling - Santis, Franco; Zona, Donatella; Bellagotti, Raffaella; Vichi, Francesca; Allegrini, Ivo (Analytical and Bioanalytical Chemistry, 2004)
Ambient ozone was measured in a forest in Castelporziano (Italy) characterised by the prevailing presence of Holm-oak trees (Quercus ilex L.) from June to November 2003. Two methods for measuring ozone were used: long-term monitoring using diﬀusive samplers at three heights within the canopy, and continuous monitoring at two heights using the UV method. Results for one week mean ozone levels above and below the canopy from the diﬀusive samplers were compared to those obtained using the automatic analyser at the same levels. A good correlation between the two sampling techniques was found. Continuous monitoring showed a daily cycle with a midday maximum and a nocturnal minimum. While the forest ﬂoor consistently had the lowest ozone concentration, there were no diﬀerences during most daytime hours. The midday maximum is clearly due to downward mixing with O3 -rich air from above. The night-time ozone decay within the canopy is the result of dry deposition of O3 and most likely due to reaction with biogenically produced NO. AOT40 within and above the canopy mostly exceeded the critical levels
Keywords: Diffusive sampling; mediterranean forest; Ozone (vertical profile)

Ozone monitoring in a Mediterranean forest using diffusive and continuous sampling - Santis, Franco; Zona, Donatella; Bellagotti, Raffaella; Vichi, Francesca; Allegrini, Ivo (Analytical and Bioanalytical Chemistry, 2004)
Ambient ozone was measured in a forest in Castelporziano (Italy) characterised by the prevailing presence of Holm-oak trees (Quercus ilex L.) from June to November 2003. Two methods for measuring ozone were used: long-term monitoring using diﬀusive samplers at three heights within the canopy, and continuous monitoring at two heights using the UV method. Results for one week mean ozone levels above and below the canopy from the diﬀusive samplers were compared to those obtained using the automatic analyser at the same levels. A good correlation between the two sampling techniques was found. Continuous monitoring showed a daily cycle with a midday maximum and a nocturnal minimum. While the forest ﬂoor consistently had the lowest ozone concentration, there were no diﬀerences during most daytime hours. The midday maximum is clearly due to downward mixing with O3 -rich air from above. The night-time ozone decay within the canopy is the result of dry deposition of O3 and most likely due to reaction with biogenically produced NO. AOT40 within and above the canopy mostly exceeded the critical levels
The following values have no corresponding Zotero field: publisher: Springer-Verlag
Keywords: Diffusive sampling; mediterranean forest; Ozone (vertical profile)

The periderm development in Quercus suber - Graça, José; Pereira, Helena (IAWA Journal, 2004)
In the cork oak (Quercus suber L.), the phellogen differentiates during the first year of growth in the cell layer immediately under the epidermis and divides to form 3–6 suberized phellem cells. Division of the phellogen only occurs after suberization of the previous divided cell. During the first four years of growth, the phellem cells have tannin-filled lumens and it is only in the 5th to 7th years that they acquire the characteristics of ʻadultʼ cork cells with empty lumens and thin suberized walls. The len- ticels are formed by the lenticular phellogen, which differentiates under the stomata and has a high meristematic activity. In this region, the cells are unsuberized, with a loose arrangement and intercellular voids, consti- tuting the filling or complementary tissue. After three years, the lenticels appear as small protuberances that soon become conspicuous. Inclusions of sclerenchymatous nodules and isolated sclereids occur occasionally mostly in the vicinity of, or in, the lenticels.
Keywords: Cork; epidermis; lenticels; phellem; phellogen; Quercus suber

Refining vegetation simulation models: From plant functional types to bioclimatic affinity groups of plants - Laurent, J.-M.; Bar-Hen, A.; François, L.; Ghislain, M.; Cheddadi, R. (Journal of Vegetation Science, 2004)
Question: How to refine simulations based on a global vegetation model in order to apply it to regional scale? Location: Europe from 35° N to 71° N and 25° W to 70° E. Methods: Geographical ranges of European plants were georeferenced and used with monthly mean climatic data (diurnal temperature ranges, ground frost frequencies, precipitation, relative humidity, rain frequencies, amount of sunshine hours and temperature) and growing degree days to infer climatic boundaries for 320 taxa. We performed a discriminant analysis to define their potential geographic ranges. Hierarchical clustering was computed on potential ranges. Results: Clustering provided 25 Bioclimatic Affinity Groups (BAG) of plants consisting of 13 tree, seven shrub and five herb groups. These B AGs are characterized by different geographical ranges and climatic tolerances and requirements. Conclusion: The use of monthly data instead of annual values improved the prediction of potential distribution ranges and highlighted the importance of climate seasonality for defining the plant groups with accuracy. The B AGs are detailed enough to provide finer reconstructions and simulations of the vegetation at the regional scale.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: CARAIB; Discriminant analysis; Hierarchical clusteranalysis; Moisture; pollen; Seasonality; Temperature; Vegetation distribution

Refining vegetation simulation models: From plant functional types to bioclimatic affinity groups of plants - Laurent, J.-M.; Bar-Hen, A; François, L; Ghislain, M; Cheddadi, R (Journal of Vegetation Science, 2004)
Question: How to refine simulations based on a global vegetation model in order to apply it to regional scale? Location: Europe from 35° N to 71° N and 25° W to 70° E. Methods: Geographical ranges of European plants were georeferenced and used with monthly mean climatic data (diurnal temperature ranges, ground frost frequencies, precipitation, relative humidity, rain frequencies, amount of sunshine hours and temperature) and growing degree days to infer climatic boundaries for 320 taxa. We performed a discriminant analysis to define their potential geographic ranges. Hierarchical clustering was computed on potential ranges. Results: Clustering provided 25 Bioclimatic Affinity Groups (BAG) of plants consisting of 13 tree, seven shrub and five herb groups. These B AGs are characterized by different geographical ranges and climatic tolerances and requirements. Conclusion: The use of monthly data instead of annual values improved the prediction of potential distribution ranges and highlighted the importance of climate seasonality for defining the plant groups with accuracy. The B AGs are detailed enough to provide finer reconstructions and simulations of the vegetation at the regional scale.
Keywords: CARAIB; Discriminant analysis; Hierarchical clusteranalysis; Moisture; pollen; Seasonality; Temperature; Vegetation distribution

Relación entre composición y densidad de la cubierta vegetal leñosa y las características superficiales del suelo en Bosques Mixtos de Quercus del Sur de la Península Ibérica - GARCÍA, L V; POLO, A; Maltez-Moro, S; Gutiérrez, E; PÉREZ-RAMOS, I M; JORDÁN, A; MARTÍNEZ-ZAVALA, L; MARAÑÓN, T (Tendencias Actuales de la Ciencia del Suelo, 2004)
We studied the relationships between different estimates of the woody canopy density; different estimates of litter release and accumulation, and different soil properties (mainly soil reaction and macronutrient level) which have been recognised as potentially relevant for plant establishment and development in mixed Quercus forest from Natural Park “do Sudoeste Alentejano e Costa Vicentina”, Portugal (with Q. suber, Q. faginea as dominant tree species) and Natural Park “Los Alcornocales”, Spain (with Q. suber and Q. canariensis). We have found 1) A highly significant, quantitative, relationship between litter accumulation and overall canopy density. These relationships can be established either by using objective (but time-consuming) measures (by sampling or using ad hoc measuring devices) or by calibrated by-eye estimates of three simultaneous observers; 2) A significant relationship between some soil properties (N, P, ammonium) and both canopy density and litter accumulation. We conclude that these relationships are interesting in two ways: 1) They may allow to establish ‘ecotransfer functions’ for these forests (i.e. estimates o predictions about surface litter accumulation or surface values for soil properties, as organic carbon, N or P contents, by using quick field estimates of canopy density or even remote sensing estimates of canopy density), after suitable calibrations. 2) Since some soil chemical properties with known ecological relevance (e.g. C, N, P contents, soil reaction) in forest regeneration may change in a close relationship with other more studied, better known, ecological factors (light, moisture, temperature), attention should be paid to separate direct (e.g. light limitation) versus indirect (soil or litter mediated) effects of woody canopy when evaluating ecological responses at the understorey, while studying forest regeneration processes.
Keywords: acumulación de hojarasca; densidad cubierta vegetal leñosa; dosel leñoso; Quercus (voyant); suelo

Relación entre composición y densidad de la cubierta vegetal leñosa y las características superficiales del suelo en Bosques Mixtos de Quercus del Sur de la Península Ibérica - Garcia, L. V.; POLO, A.; Maltez-Moro, S.; GUTIÉRREZ, E.; PÉREZ-RAMOS, I. M.; JORDÁN, A.; MARTÍNEZ-ZAVALA, L.; MARAÑON, T. (Tendencias Actuales de la Ciencia del Suelo, 2004)
We studied the relationships between different estimates of the woody canopy density; different estimates of litter release and accumulation, and different soil properties (mainly soil reaction and macronutrient level) which have been recognised as potentially relevant for plant establishment and development in mixed Quercus forest from Natural Park “do Sudoeste Alentejano e Costa Vicentina”, Portugal (with Q. suber, Q. faginea as dominant tree species) and Natural Park “Los Alcornocales”, Spain (with Q. suber and Q. canariensis). We have found 1) A highly significant, quantitative, relationship between litter accumulation and overall canopy density. These relationships can be established either by using objective (but time-consuming) measures (by sampling or using ad hoc measuring devices) or by calibrated by-eye estimates of three simultaneous observers; 2) A significant relationship between some soil properties (N, P, ammonium) and both canopy density and litter accumulation. We conclude that these relationships are interesting in two ways: 1) They may allow to establish ‘ecotransfer functions’ for these forests (i.e. estimates o predictions about surface litter accumulation or surface values for soil properties, as organic carbon, N or P contents, by using quick field estimates of canopy density or even remote sensing estimates of canopy density), after suitable calibrations. 2) Since some soil chemical properties with known ecological relevance (e.g. C, N, P contents, soil reaction) in forest regeneration may change in a close relationship with other more studied, better known, ecological factors (light, moisture, temperature), attention should be paid to separate direct (e.g. light limitation) versus indirect (soil or litter mediated) effects of woody canopy when evaluating ecological responses at the understorey, while studying forest regeneration processes.
The following values have no corresponding Zotero field: periodical: Tendencias Actuales de la Ciencia del Suelo
Keywords: acumulación de hojarasca; densidad cubierta vegetal leñosa; dosel leñoso; Quercus (voyant); suelo

Respostas morfológicas e fisiológicas das folhas de duas espécies mediterrânicas a factores ambientais durante o Inverno - Oliveira, Graca; Penuelas, Josep (Revista de Biologia, 2004)

The role of disturbance in the co-existence of the evergreen Quercus ilex and the deciduous Quercus cerrioides - Bonfil, Consuelo; Cortés, Pilar; Espelta, Josep Maria; Retana, Javier (Journal of Vegetation Science, 2004)
Question: Which is the response of the evergreen Quercus ilex and the deciduous Q. cerrioides to repeated disturbances? Location: central Catalonia (northeastern Spain), in the areas affected by two of the largest historically recorded wildfires in NE Spain: the Bages-Berguedà fire (24 300 ha forested area burned in July 1994), and the Solsonès fire (14 300 ha burned in 1998). Methods: Survival and growth of individuals of Quercus ilex and Q. cerrioides were evaluated in plants subjected to different fire histories and experimental disturbances (burning, cutting or clipping) applied either before or after summer. Results: Survival was high (> 99%), with both species showing a similar high resistance to disturbances. Growth after experimental disturbance was positively related to the size of the individual before the latest forest fire occurred. Fire history had a large effect on resprout growth, as the repeated incidence of disturbances lowered the capacity of individuals to grow. The type and season of experimental disturbance experienced by plants had a large effect. Individuals that experienced total above-ground loss had lower growth rates than those with partial loss. A similar pattern was observed in individuals disturbed after the summer in relation to those disturbed before summer. Conclusions: The larger growth rates recorded in Q. cerrioides across all fire histories and experimental treatments, and the higher vulnerability of Q. ilex to increased fire frequency, intensity of experimental disturbance, and disturbance season, provide evidence for the relatively high susceptibility of the latter to repeated disturbances. This view disagrees with the larger resilience of this species compared to co-existing deciduous oaks, as reported.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: Burning; clipping; fire; Growth; Mediterranean Region; Quercus; resilience; resprouting; Survival

The role of disturbance in the co-existence of the evergreen Quercus ilex and the deciduous Quercus cerrioides - Bonfil, Consuelo; Cortés, Pilar; Espelta, Josep Maria; Retana, Javier (Journal of Vegetation Science, 2004)
Question: Which is the response of the evergreen Quercus ilex and the deciduous Q. cerrioides to repeated disturbances? Location: central Catalonia (northeastern Spain), in the areas affected by two of the largest historically recorded wildfires in NE Spain: the Bages-Berguedà fire (24 300 ha forested area burned in July 1994), and the Solsonès fire (14 300 ha burned in 1998). Methods: Survival and growth of individuals of Quercus ilex and Q. cerrioides were evaluated in plants subjected to different fire histories and experimental disturbances (burning, cutting or clipping) applied either before or after summer. Results: Survival was high (> 99%), with both species showing a similar high resistance to disturbances. Growth after experimental disturbance was positively related to the size of the individual before the latest forest fire occurred. Fire history had a large effect on resprout growth, as the repeated incidence of disturbances lowered the capacity of individuals to grow. The type and season of experimental disturbance experienced by plants had a large effect. Individuals that experienced total above-ground loss had lower growth rates than those with partial loss. A similar pattern was observed in individuals disturbed after the summer in relation to those disturbed before summer. Conclusions: The larger growth rates recorded in Q. cerrioides across all fire histories and experimental treatments, and the higher vulnerability of Q. ilex to increased fire frequency, intensity of experimental disturbance, and disturbance season, provide evidence for the relatively high susceptibility of the latter to repeated disturbances. This view disagrees with the larger resilience of this species compared to co-existing deciduous oaks, as reported.
Keywords: Burning; clipping; fire; Growth; Mediterranean Region; Quercus; resilience; resprouting; Survival

The role of land abandonment in landscape dynamics in the SPA ‘Encinares del rı́o Alberche y Cofio, Central Spain, 1984–1999 - Romero-Calcerrada, Raúl; Perry, George L. W. (Landscape and Urban Planning, 2004)
Land use has changed dramatically over the last 30–40 years throughout the Mediterranean. Much of this change has been driven by shifts in agricultural and socio-economic policy. This paper explores landscape dynamics in the SPA ‘Encinares del r´ıo Alberche y Coﬁo’ Central Spain between 1984 and 1999 in an area of approximately 83,000 ha. Categorical land cover maps, derived from three (1984, 1991 and 1999) remotely sensed Landsat images, are analyzed using a suite of landscape pattern metrics, and a simple transition matrix model of landscape change is developed. As with other landscapes in the Mediterranean a key trend is that of the abandonment of agricultural land and its subsequent succession to scrubland and woodland. Although there were signiﬁcant composition changes in the landscape over the study period conﬁgurational changes are less evident. The transition matrix model suggests that there were differences in landscape dynamics between 1984–1991 and 1991–1999—most importantly an increase in the rate of land abandonment is evident. The model predicts a steady state landscape containing a higher abundance of scrubland and woodland, and a corresponding decline in pastureland and cropland. Finally, the underlying socio-economic and other drivers of landscape change in the Encinares del r´ıo Alberche y Coﬁo and some of the implications of recent changes are discussed in terms of increased wildﬁre risk. Sustainable management of landscapes to protect biodiversity requires the type of study described here. A necessary pre-requisite of such management activities or planning is an assessment of changes in landscape pattern and process, the social and economic pressures driving them, and their possible effects on ecosystem structure and function.
Keywords: Central Spain; Human disturbance; Land abandonment; landscape change; landscape heterogeneity; landscape metric; special protection areas (spa); transition matrix model

The role of land abandonment in landscape dynamics in the SPA ‘Encinares del rı́o Alberche y Cofio, Central Spain, 1984–1999 - Romero-Calcerrada, Raúl; Perry, George L W (Landscape and Urban Planning, 2004)
Land use has changed dramatically over the last 30–40 years throughout the Mediterranean. Much of this change has been driven by shifts in agricultural and socio-economic policy. This paper explores landscape dynamics in the SPA ‘Encinares del r´ıo Alberche y Coﬁo’ Central Spain between 1984 and 1999 in an area of approximately 83,000 ha. Categorical land cover maps, derived from three (1984, 1991 and 1999) remotely sensed Landsat images, are analyzed using a suite of landscape pattern metrics, and a simple transition matrix model of landscape change is developed. As with other landscapes in the Mediterranean a key trend is that of the abandonment of agricultural land and its subsequent succession to scrubland and woodland. Although there were signiﬁcant composition changes in the landscape over the study period conﬁgurational changes are less evident. The transition matrix model suggests that there were differences in landscape dynamics between 1984–1991 and 1991–1999—most importantly an increase in the rate of land abandonment is evident. The model predicts a steady state landscape containing a higher abundance of scrubland and woodland, and a corresponding decline in pastureland and cropland. Finally, the underlying socio-economic and other drivers of landscape change in the Encinares del r´ıo Alberche y Coﬁo and some of the implications of recent changes are discussed in terms of increased wildﬁre risk. Sustainable management of landscapes to protect biodiversity requires the type of study described here. A necessary pre-requisite of such management activities or planning is an assessment of changes in landscape pattern and process, the social and economic pressures driving them, and their possible effects on ecosystem structure and function.
Keywords: Central Spain; Human disturbance; Land abandonment; landscape change; landscape heterogeneity; landscape metric; special protection areas (spa); transition matrix model

Soil quality and vulnerability in a Mediterranean natural ecosystem of Central Italy. - Francaviglia, R.; Gataleta, L.; Marchionni, M.; Trinchera, A.; Aromolo, R.; Benedetti, A.; Nisini, L.; Morselli, L.; Brusori, B.; Olivieri, P.; Bernardi, E. (Chemosphere, 2004)
Wet and dry atmospheric depositions and soil chemical and microbiological properties were determined in a Mediterranean natural ecosystem of Central Italy near Rome (Castelporziano Estate). The monitoring of depositions permitted us to quantify the exceedances of S and N compounds (expressed as eqH(+)ha(-1)year(-1)) over the critical loads of acidity. Critical loads, i.e. the quantity of a substance which a part of the environment can tolerate without adverse effects occurring, were determined adopting the level 0 methodology following the UN/ECE Convention on Long-range Transboundary Air Pollution. Deposition data were available for the period 1992-1997, and acidity exceedances were referred to the main vegetation types present in the area. Results showed that most part of the Estate has a medium degree of vulnerability to acidification, and the corresponding risk of acidification deriving from the exceedances of atmospheric deposition was rather low. The study of soil chemical and microbiological properties included mainly total soil organic carbon (SOC), microbial biomass-C, biomass-C/SOC, soil respiration, and metabolic quotient (qCO2). Soil organic C metabolism has been discussed on the basis of the results from eight sampling sites.
The following values have no corresponding Zotero field: accession-num: 14987944
Keywords: Acidification; Atmospheric depositions; Biological indicators; Critical loads; Soil microbial biomass; Soil organic carbon

Soil quality and vulnerability in a Mediterranean natural ecosystem of Central Italy. - Francaviglia, R; Gataleta, L; Marchionni, M; Trinchera, A; Aromolo, R; Benedetti, A; Nisini, L; Morselli, L; Brusori, B; Olivieri, P; Bernardi, E (Chemosphere, 2004)
Wet and dry atmospheric depositions and soil chemical and microbiological properties were determined in a Mediterranean natural ecosystem of Central Italy near Rome (Castelporziano Estate). The monitoring of depositions permitted us to quantify the exceedances of S and N compounds (expressed as eqH(+)ha(-1)year(-1)) over the critical loads of acidity. Critical loads, i.e. the quantity of a substance which a part of the environment can tolerate without adverse effects occurring, were determined adopting the level 0 methodology following the UN/ECE Convention on Long-range Transboundary Air Pollution. Deposition data were available for the period 1992-1997, and acidity exceedances were referred to the main vegetation types present in the area. Results showed that most part of the Estate has a medium degree of vulnerability to acidification, and the corresponding risk of acidification deriving from the exceedances of atmospheric deposition was rather low. The study of soil chemical and microbiological properties included mainly total soil organic carbon (SOC), microbial biomass-C, biomass-C/SOC, soil respiration, and metabolic quotient (qCO2). Soil organic C metabolism has been discussed on the basis of the results from eight sampling sites.
Keywords: Acidification; Atmospheric depositions; Biological indicators; Critical loads; Soil microbial biomass; Soil organic carbon

Spatial structure and land-cover use in a low-density Mediterranean population of Eurasian badgers - Rosalino, Luís Miguel; Macdonald, David White; Santos-Reis, Margarida (Canadian Journal of Zoology, 2004)
Eurasian badgers, Meles meles (L., 1758), have an extensive geographic range throughout which their social organization varies. Their capacity for intraspecific variation can now best be understood by studying them in landscapes that differ from the lush, lowland farmland where their tendency to form large groups has been most intensively investigated. Badgers in cork oak (Quercus suber L.) woodland are thus a priority for study, as this Mediterranean landscape provides an extreme contrast to those studied elsewhere. In this habitat in Portugal, we found 0.36–0.48 badgers/km2, one of the lowest population densities recorded in Western Europe. Here, individuals used seasonally stable home ranges that averaged 4.46 km2 and that were occupied by 3–4 adults plus 3–4 cubs of the year. In this landscape, badgers selectively used cork oak woodland with understory and riparian vegetation. As predicted by the resource dispersion hypothesis, home-range size was positively correlated with food-patch dispersion. In southwestern Portugal, badgers depend upon an environmental mosaic such as olive groves and orchards and vegetable gardens for food and cork oak woodlands for shelter and protection.
doi: 10.1139/z04-130doi: 10.1139/z04-130The following values have no corresponding Zotero field: publisher: NRC Research Press
Keywords: cork oak woodland; eurasian badgers; habitat selection; resource dispersion hypothesis (PG); spatial structure

Spatial structure and land-cover use in a low-density Mediterranean population of Eurasian badgers - Rosalino, Luís Miguel; Macdonald, David White; Santos-Reis, Margarida (Canadian Journal of Zoology, 2004)
Eurasian badgers, Meles meles (L., 1758), have an extensive geographic range throughout which their social organization varies. Their capacity for intraspecific variation can now best be understood by studying them in landscapes that differ from the lush, lowland farmland where their tendency to form large groups has been most intensively investigated. Badgers in cork oak (Quercus suber L.) woodland are thus a priority for study, as this Mediterranean landscape provides an extreme contrast to those studied elsewhere. In this habitat in Portugal, we found 0.36–0.48 badgers/km2, one of the lowest population densities recorded in Western Europe. Here, individuals used seasonally stable home ranges that averaged 4.46 km2 and that were occupied by 3–4 adults plus 3–4 cubs of the year. In this landscape, badgers selectively used cork oak woodland with understory and riparian vegetation. As predicted by the resource dispersion hypothesis, home-range size was positively correlated with food-patch dispersion. In southwestern Portugal, badgers depend upon an environmental mosaic such as olive groves and orchards and vegetable gardens for food and cork oak woodlands for shelter and protection.
doi: 10.1139/z04-130
Keywords: cork oak woodland; eurasian badgers; habitat selection; resource dispersion hypothesis (PG); spatial structure

Stomatal responses to drought of mature trees and seedlings of two co-occurring Mediterranean oaks - Mediavilla, Sonia; Escudero, Alfonso (Forest Ecology and Management, 2004)
We studied stomatal responses to decreasing predawn water potential (Cpd ) and increasing leaf-to-air water vapour pressure deﬁcit (VPD) of seedlings and mature trees of two co-occurring Mediterranean oaks with contrasting leaf habits: the evergreen Quercus rotundifolia and the deciduous Quercus faginea. Our objective was to deﬁne and to compare the stomatal strategies of both speciesfordroughtresistanceandtoidentifythepossibledifferencesbetweengrowthstagesinselecteddroughtadaptationattributes. Among the mature trees, Q. rotundifolia exhibited a water-use behaviour that was more conservative than that of Q. faginea: lower maximum stomatal conductances and greater sensitivity to VPD than the deciduous species. As a result, the leaf water potential of the evergreen species never decreased along the day and along the growth season as much as in the deciduous species; this may help to guarantee longer leaf longevity by avoiding irreversible damage during the summer drought. The seedlings of the two species showed a less conservative water-use strategy in comparison with adult trees: a relatively high stomatal conductance and lower stomatal sensitivity to soil and atmospheric drought. As a consequence, leaf water potential decreased more in the seedlings along the day than in the adults. Q. rotundifolia was the species for which the most pronounced differences between growth stages were obtained. Thus, interspeciﬁc differences in response to drought disappeared in the ﬁrst stages of the life of the trees, and the seedlings of the two species showed a common strategy, probably as a response to the competition from the herbaceous layer. A low stomatal sensitivity in beneﬁt of an increase in growth would probably be a more successful strategy under the competitive conditions that seedlings experience during their establishment.
Keywords: Drought; growth stages; leaf water potential; mediterranean quercus species; Stomatal conductance; vapour pressure deficit

Stomatal responses to drought of mature trees and seedlings of two co-occurring Mediterranean oaks - Mediavilla, Sonia; Escudero, Alfonso (Forest Ecology and Management, 2004)
We studied stomatal responses to decreasing predawn water potential (Cpd ) and increasing leaf-to-air water vapour pressure deﬁcit (VPD) of seedlings and mature trees of two co-occurring Mediterranean oaks with contrasting leaf habits: the evergreen Quercus rotundifolia and the deciduous Quercus faginea. Our objective was to deﬁne and to compare the stomatal strategies of both speciesfordroughtresistanceandtoidentifythepossibledifferencesbetweengrowthstagesinselecteddroughtadaptationattributes. Among the mature trees, Q. rotundifolia exhibited a water-use behaviour that was more conservative than that of Q. faginea: lower maximum stomatal conductances and greater sensitivity to VPD than the deciduous species. As a result, the leaf water potential of the evergreen species never decreased along the day and along the growth season as much as in the deciduous species; this may help to guarantee longer leaf longevity by avoiding irreversible damage during the summer drought. The seedlings of the two species showed a less conservative water-use strategy in comparison with adult trees: a relatively high stomatal conductance and lower stomatal sensitivity to soil and atmospheric drought. As a consequence, leaf water potential decreased more in the seedlings along the day than in the adults. Q. rotundifolia was the species for which the most pronounced differences between growth stages were obtained. Thus, interspeciﬁc differences in response to drought disappeared in the ﬁrst stages of the life of the trees, and the seedlings of the two species showed a common strategy, probably as a response to the competition from the herbaceous layer. A low stomatal sensitivity in beneﬁt of an increase in growth would probably be a more successful strategy under the competitive conditions that seedlings experience during their establishment.
Keywords: Drought; growth stages; leaf water potential; mediterranean quercus species; Stomatal conductance; vapour pressure deficit

Thermal radiation, canopy temperature and evaporation from forest canopies - Jones, H G; Archer, N; Rotenberg, E (FORESTS AT THE LAND-ATMOSPHERE INTERFACE, 2004)
We review the remote sensing of canopy temperature using thermal radiation and outline the main sources of error in the measurement of emitted thermal radiation and its use in canopy temperature estimation. The theory underlying different approaches to the use of these remote estimates of canopy temperature for the estimation of evaporation from forest and other canopies is discussed. The data requirements for the different approaches for remote estimation are compared. We illustrate the application of different approaches to local (branch-level) thermal remote sensing for the estimation of evaporation rate from Quercus rotundifolia trees in Portugal.
Keywords: canopy temperature; evaporation estimation; Portugal; Quercus ilex; Remote sensing; thermal radiation

Three new species of Stibeutes and Gnotus (Hymenoptera: Ichneumonidae) from holm-oak and cork-oak Mediterranean forests - Bordera, Santiago; Hernández-Rodríguez, Estefanía (Insect Systematics & Evolution, 2004)
The new species Stibeutes hirsutus, S. calderonae and Gnotus klausi from Spanish holm-oak and cork-oak woods are described and illustrated. Data on their habitat and the phenology of S. hirsutus are reported. The species S. breviareolatus collected in a cork-oak forest is recorded for the first time for Spain. New keys for the Gnotus tenuipes species group and for the Spanish species of Stibeutes are provided.
Keywords: Gnotus; habitat; morphology; new species; phenology (PG); Stibeutes

Three new species of Stibeutes and Gnotus (Hymenoptera: Ichneumonidae) from holm-oak and cork-oak Mediterranean forests - Bordera, Santiago; Hernández-Rodríguez, Estefanía (Insect Systematics & Evolution, 2004)
The new species Stibeutes hirsutus, S. calderonae and Gnotus klausi from Spanish holm-oak and cork-oak woods are described and illustrated. Data on their habitat and the phenology of S. hirsutus are reported. The species S. breviareolatus collected in a cork-oak forest is recorded for the first time for Spain. New keys for the Gnotus tenuipes species group and for the Spanish species of Stibeutes are provided.
Keywords: Gnotus; habitat; morphology; new species; phenology (PG); Stibeutes

Topography and forest composition affecting the variability in fire severity and post-fire regeneration occurring after a large fire in the Mediterranean basin - Broncano, M. J.; Retana, J. (INTERNATIONAL JOURNAL OF WILDLAND FIRE, 2004)
This study relates the spatial variability in tree regeneration generated by fire with topography and pre-fire vegetation composition, and analyses how the pattern of fire severities determines post-fire regeneration of the dominant tree species (Pinus halepensis and Quercus ilex) in a large fire that occurred in north-eastern Spain in summer 1994. At the fire level, the proportion of the different fire severities in the burned area was characteristic of large fires that burn with high severity. At the level of plot, the variability of fire severity in the study site depended on two topographic characteristics: elevation and aspect. Plots burned with high fire severity were distributed at higher altitude than less severely burned plots, which were mainly distributed in south- and east-facing slopes. Fire severity also increased with Q. ilex density in the stand. The mosaic of fire severities determined both plant mortality and seedling regeneration. Mortality of stems caused by fire was very high in both species, but many Q. ilex individuals resprouted after fire. Seedling regeneration of P. halepensis showed large differences among plots in the burned area, reflecting large spatial variability due to the elevation gradient, the variation in density of adult pine trees, and the spatial variability created by fire.
The following values have no corresponding Zotero field: pub-location: 150 OXFORD ST, PO BOX 1139, COLLINGWOOD, VICTORIA 3066, AUSTRALIA publisher: C S I R O PUBLISHING
Keywords: mortality; post-fire regeneration; resprouting

Topography and forest composition affecting the variability in fire severity and post-fire regeneration occurring after a large fire in the Mediterranean basin - Broncano, M J; RETANA, J (INTERNATIONAL JOURNAL OF WILDLAND FIRE, 2004)
This study relates the spatial variability in tree regeneration generated by fire with topography and pre-fire vegetation composition, and analyses how the pattern of fire severities determines post-fire regeneration of the dominant tree species (Pinus halepensis and Quercus ilex) in a large fire that occurred in north-eastern Spain in summer 1994. At the fire level, the proportion of the different fire severities in the burned area was characteristic of large fires that burn with high severity. At the level of plot, the variability of fire severity in the study site depended on two topographic characteristics: elevation and aspect. Plots burned with high fire severity were distributed at higher altitude than less severely burned plots, which were mainly distributed in south- and east-facing slopes. Fire severity also increased with Q. ilex density in the stand. The mosaic of fire severities determined both plant mortality and seedling regeneration. Mortality of stems caused by fire was very high in both species, but many Q. ilex individuals resprouted after fire. Seedling regeneration of P. halepensis showed large differences among plots in the burned area, reflecting large spatial variability due to the elevation gradient, the variation in density of adult pine trees, and the spatial variability created by fire.
Keywords: mortality; post-fire regeneration; resprouting

Trace metal fluxes in bulk deposition, throughfall and stemflow at two evergreen oak stands in NE Spain subject to different exposure to the industrial environment - Avila, Anna; Rodrigo, Anselm (Atmospheric Environment, 2004)
We compare here the bulkdeposition, throughfall and stemﬂow ﬂuxes of dissolved trace metals in two holm oak (Quercus ilex L.) forests in the Montseny Mountains (NE Spain) with the aim of: (1) applying different methods to distinguish between dry deposition and canopy leaching and (2) to add to the almost non-existing deposition measurements for dissolved Cu, Pb, Mn, V, Zn, Ni and Cd in two Spanish forests differentially exposed to the urban and industrial environment. No signiﬁcant differences in mean bulkdeposition concentrations or ﬂuxes were found between sites, indicating little differential effect of the urban/industrial environment on bulkprecipitation chemistry. At both sites, throughfall and stemﬂow ﬂuxes increased relative to bulkdeposition for all elements, except for Zn and Cd. The relative contribution of leaching and dry deposition was evaluated through: (1) the seasonal variability of throughfall, (2) regressions of element ﬂuxes on water ﬂux in net throughfall, (3) washing branches and metacrylate plates, and (4) the sequential washing of branches. Results indicated that leaching was the main enrichment process for Mn. For Ni, except the sequential washings, all other evidences also pointed to leaching. For Cu, Pb, Zn, Cd and V there was ample evidence for dry deposition. The fact that Zn and Cd had negative net throughfall ﬂuxes indicated that canopy uptake was greater than deposition (wet plus dry). Net throughfall ﬂuxes pointed to higher dry deposition onto the canopies in the more exposed site, but the occurrence of uptake impeached quantiﬁcation. Therefore, dry deposition was estimated from the recovered quantities from experimental washings of foliage, taken to represent the impaction of small particles onto the canopy. The foliage-wash ﬂuxes were, for Zn, Cu and Pb, respectively, 407, 25 and 16 g ha 1 yr 1 at the sheltered site and 423, 38 and 26 g ha 1 yr 1 at the exposed site. Deposition in bulkprecipitation (wet deposition+an unknown fraction of dry deposition mostly accounted by coarse particles settling gravitationally) was lower: 222, 6.3 and 6.5 g ha 1 yr 1 for Zn, Cu and Pb, respectively, averaged for the two sites
Keywords: Dry deposition; Leaching; Mediterranean forests; surrogate surfaces; throughfall; Trace metals

Trace metal fluxes in bulk deposition, throughfall and stemflow at two evergreen oak stands in NE Spain subject to different exposure to the industrial environment - Avila, Anna; Rodrigo, Anselm (Atmospheric Environment, 2004)
We compare here the bulkdeposition, throughfall and stemﬂow ﬂuxes of dissolved trace metals in two holm oak (Quercus ilex L.) forests in the Montseny Mountains (NE Spain) with the aim of: (1) applying different methods to distinguish between dry deposition and canopy leaching and (2) to add to the almost non-existing deposition measurements for dissolved Cu, Pb, Mn, V, Zn, Ni and Cd in two Spanish forests differentially exposed to the urban and industrial environment. No signiﬁcant differences in mean bulkdeposition concentrations or ﬂuxes were found between sites, indicating little differential effect of the urban/industrial environment on bulkprecipitation chemistry. At both sites, throughfall and stemﬂow ﬂuxes increased relative to bulkdeposition for all elements, except for Zn and Cd. The relative contribution of leaching and dry deposition was evaluated through: (1) the seasonal variability of throughfall, (2) regressions of element ﬂuxes on water ﬂux in net throughfall, (3) washing branches and metacrylate plates, and (4) the sequential washing of branches. Results indicated that leaching was the main enrichment process for Mn. For Ni, except the sequential washings, all other evidences also pointed to leaching. For Cu, Pb, Zn, Cd and V there was ample evidence for dry deposition. The fact that Zn and Cd had negative net throughfall ﬂuxes indicated that canopy uptake was greater than deposition (wet plus dry). Net throughfall ﬂuxes pointed to higher dry deposition onto the canopies in the more exposed site, but the occurrence of uptake impeached quantiﬁcation. Therefore, dry deposition was estimated from the recovered quantities from experimental washings of foliage, taken to represent the impaction of small particles onto the canopy. The foliage-wash ﬂuxes were, for Zn, Cu and Pb, respectively, 407, 25 and 16 g ha 1 yr 1 at the sheltered site and 423, 38 and 26 g ha 1 yr 1 at the exposed site. Deposition in bulkprecipitation (wet deposition+an unknown fraction of dry deposition mostly accounted by coarse particles settling gravitationally) was lower: 222, 6.3 and 6.5 g ha 1 yr 1 for Zn, Cu and Pb, respectively, averaged for the two sites
Keywords: Dry deposition; Leaching; Mediterranean forests; surrogate surfaces; throughfall; Trace metals

USE OF THERMAL IMAGING TECHNIQUES AND XANTHOPHYLLS CONTENT FOR DETERMINATION OF STRESS IN CORK OAK (QUERCUS SUBER L.) - Tronina, L.; Grant, O. M.; Ramalho, J. C.; Chaves, M. M. (ACTA PHYSIOLOGIAE PLANTARUM, 2004)
Understanding the responses of cork oak (Quercus suber L.) to actual and predicted summer conditions is essential to determine the future sustainability of cork oak woodlands in Iberia. Thermal imaging may provide a rapid method for monitoring the extent of stress. The ecophysiology of cork trees was studied over three years. Three treatments were applied by means of rainfall capture and irrigation, with plots receiving 120%, 100%, or 80% of natural precipitation. Despite stomatal closure, detected using both thermal imaging and porometry, leaf water potential fell during the summer, most drastically during the third year of accumulative stress. The quantum efficiency (ΦPSII) and the maximum efficiency Formula of photosystem II also fell more intensely over the third summer, while non-photochemical quenching (NPQ) increased. The reduced precipitation treatment sporadically further reduced leaf water potential, stomatal conductance (gs), IG (an index of gs derived from thermal imaging), ΦPSII, and Formula, and increased leaf temperature and NPQ. It is concluded that these are very resilient trees since they were only severely affected in the third year of severe drought (the third year registering 45% less rainfall than average), and removing 20% of rainfall had a limited impact.
Key words: ASKey words: ASThe following values have no corresponding Zotero field: pub-location: TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY publisher: SPRINGER HEIDELBERG
Keywords: Quercus suber L.; Stress; thermal imaging

USE OF THERMAL IMAGING TECHNIQUES AND XANTHOPHYLLS CONTENT FOR DETERMINATION OF STRESS IN CORK OAK (QUERCUS SUBER L.) - Tronina, L; Grant, O M; Ramalho, J C; Chaves, M M (ACTA PHYSIOLOGIAE PLANTARUM, 2004)
Understanding the responses of cork oak (Quercus suber L.) to actual and predicted summer conditions is essential to determine the future sustainability of cork oak woodlands in Iberia. Thermal imaging may provide a rapid method for monitoring the extent of stress. The ecophysiology of cork trees was studied over three years. Three treatments were applied by means of rainfall capture and irrigation, with plots receiving 120%, 100%, or 80% of natural precipitation. Despite stomatal closure, detected using both thermal imaging and porometry, leaf water potential fell during the summer, most drastically during the third year of accumulative stress. The quantum efficiency (ΦPSII) and the maximum efficiency Formula of photosystem II also fell more intensely over the third summer, while non-photochemical quenching (NPQ) increased. The reduced precipitation treatment sporadically further reduced leaf water potential, stomatal conductance (gs), IG (an index of gs derived from thermal imaging), ΦPSII, and Formula, and increased leaf temperature and NPQ. It is concluded that these are very resilient trees since they were only severely affected in the third year of severe drought (the third year registering 45% less rainfall than average), and removing 20% of rainfall had a limited impact.
Key words: AS
Keywords: Quercus suber L.; Stress; thermal imaging

Variation of stand structure and regeneration of Mediterranean holm oak along a grazing intensity gradient - Cierjacks, a.; Hensen, I (Plant Ecology (formerly Vegetatio), 2004)
Mediterranean ecosystems are traditionally inﬂuenced by human disturbance. In the mountain chains of southeastern Spain, holm oak forests representing the potential natural vegetation are currently highly fragmented and subjected to extensive grazing by goats and sheep. This grazing activity by large herbivores has important impacts on community structure and dynamics of the remaining remnants because several processes associated with reproduction are affected. The present research analyses the variation of stand structure and regeneration of six forests dominated by Quercus ilex along a gradient of increasing grazing intensity. Stands of higher grazing intensity are characterized by a lower trunk number. Particularly, trees 1.3 m height and diameter classes 20 cm are clearly less represented. In addition, more intensively grazed forests show a highly aggregated dispersion of trees, which might be explained by an increase of clonally produced ramets by silvipastoral use. On the other hand, no Quercus ilex seedlings were found in any of the stands examined, although acorn production was high and did not correlate with grazing intensity. However, grazing clearly inﬂuences the quality of acorn harvest. We found a signiﬁcant negative correlation between acorn length, acorn mass and grazing intensity and a positive correlation between the percentage of aborted acorns, acorn predation and herbivore activity. Thus, management of grazing in holm oak forests must take the high inﬂuence that livestock exerts on the regeneration of Quercus ilex into account, and maximum sustainable grazing intensity should be signiﬁcantly lower than 0.8 animals per ha.
Keywords: acorn predation; acorn quality; forest conservation; grazing intensity; Quercus ilex; south-eastern spain; sustainable land-use; vegetative reproduction

Vegetation dynamics of Mediterranean shrublands in former cultural landscape at Grazalema Mountains, South Spain - Gallego Fernández, Juan B.; Rosario García Mora, M.; García Novo, Francisco (Plant Ecology (formerly Vegetatio), 2004)
Plant community dynamics in Mediterranean basin ecosystems are mainly driven by an alternation of episodes of human intervention and land abandonment. As a result, a mosaic of plant communities has evolved following different stages of degradation and regeneration. Some authors has relate secondary succession to abandoned culture lands and regeneration to natural systems with abandonment of livestock or forestry exploitation. In this paper, the dynamics of shrublands in mid-mountain areas in the South of Spain after disturbance and land abandonment has been studied. The plant cover and 13 environmental variables of 137 selected sites on the Grazalema mountains was analysed to determine the vegetation pattern in relation to environmental factors and the succession types, either regenerative or secondary succession. The results show that today the Grazalema mountains have a heterogeneous vegetation pattern. Besides physical factors such as altitude or soil pH, human disturbance has modulated current vegetation patterns and dynamics. Two main types of vegetation dynamics can be distinguished in the study area. In areas affected by cutting, regeneration results in rich and dense shrub land, with resprouters as dominant species. In areas affected by recurrent wildﬁres or agriculture, secondary succession became dominant, resulting in less diverse shrubland, due to the dominance of seeders and decrease in resprouter species richness and cover.
Keywords: Human disturbance; Land abandonment; Mediterranean vegetation; Regen- erative succession; Regenerative strategies; Secondary succession

Winter photoinhibition in the field involves different processes in four co-occurring Mediterranean tree species - Martínez-Ferri, E; Manrique, E; Valladares, F; Balaguer, L (Tree Physiology, 2004)
Photoinhibition was examined in four co-occurring Mediterranean evergreen tree species during two consecutive winters. In response to low temperatures and saturating light, Juniperus phoenicea L., Pinus halepensis Mill., Quercus coccifera L. and Q. ilex ssp. ballota (Desf.) Samp. exhibited marked chronic photoinhibition, indicated by low predawn maximal photochemical efficiency of photosystem II (PSII) (Fv/Fm). Low Fv/Fm values were correlated with high concentrations of xanthophyll cycle components (VAZ) and with the maintenance of high concentrations of zeaxanthin overnight (DPSpd). In all species, however, chronic photoinhibition was enhanced as the winter progressed in the absence of changes in DPSpd, suggesting cumulative damage toward the end of winter.Photoinhibition differed among species: P. halepensis always displayed significantly higher Fv/Fm values; and Q. coccifera had the lowest Fv/Fm values, showing a high sensitivity to the combination of high light and low temperatures. Differences among species were not fully explained by differences in the xanthophyll pool or its de-epoxidation state. Chronic photoinhibition overlapped with a dynamic photoinhibition as shown by the low values of photochemical efficiency of the open reaction centers of PSII at midday. Winter photoprotective strategies differed among species and may involve photoprotective mechanisms in addition to those associated with xanthophylls. The observed species-specific differences matched results obtained for the same species in summer; however, comparison of the two seasons suggests that the higher VAZ concentration observed in winter has an additional structural photoprotective role.
From Duplicate 2 (Winter photoinhibition in the field involves different processes in four co-occurring Mediterranean tree species - Martínez-Ferri, E; Manrique, E; Valladares, F; Balaguer, L)
Keywords: chlorophyll; Chlorophyll: physiology; Juniperus; Juniperus: physiology; photoprotection; Pinus; Pinus: physiology; Plant Leaves; Plant Leaves: physiology; Quercus; Quercus: physiology; Seasons; Sunlight; Trees; Trees: physiology; xanthophyll cycle

A 10-kDa class-CI sHsp protects E-coli from oxidative and high-temperature stress - Jofre, A; Molinas, M; Pla, M (PLANTA, 2003)
We report on a new cDNA clone (Qshsp10.4-CI) of a Quercus suber L. class-CI small heat-shock protein (sHsp) obtained from cork (phellem), a highly oxidatively stressed plant tissue. The deduced gene product lacks the C-terminal extension and the consensus I region of the alpha-crystallin domain, being the most C-terminally truncated sHsp reported to date. In an attempt to prove that a protective function is possible for such a truncated sHsp, we overexpressed in Escherichia coli three recombinant sHsp-CIs, one (rQsHsp10.4-CI) showing the same truncation as Qshsp10.4-CI, a second (rN49) lacking the whole alpha-crystallin domain, and a third (rN153) consisting of a full-length sHsp-CI. The overexpression of rN153 and, remarkably, rQsHsp10.4-CI but not rN49 enhanced cell viability under high temperature and, interestingly, under oxidative stress. These results show that the C-terminal extension and the consensus I region of the alpha-crystallin domain are dispensable, but amino acids 1-41 of the alpha-crystallin domain (including the consensus II region) are essential for the protective activity of sHsp-CIs. On the other hand, two-dimensional immunodetection patterns showed accumulation of ca. 10-kDa sHsp-CI immunorelated polypeptides in cork and other oxidatively stressed tissues but not in control and heat-stressed tissues. We discuss the possible role of highly truncated sHsps in relation to oxidative stress.
Keywords: chaperone activity; heat stress; Oxidative stress; Quercus; small heat-shock protein

12CO2 emission from different metabolic pathways measured in illuminated and darkened C3 and C4 leaves at low, atmospheric and elevated CO2 concentration - Pinelli, Paola; Loreto, Francesco (Journal of Experimental Botany, 2003)
The detection of 12CO2 emission from leaves in air containing 13CO2 allows simple and fast determination of the CO2 emitted by different sources, which are separated on the basis of their labelling velocity. This technique was exploited to investigate the controversial effect of CO2 concentration on mitochondrial respiration. The 12CO2 emission was measured in illuminated and darkened leaves of one C4 plant and three C3 plants maintained at low (30–50 ppm), atmospheric (350–400 ppm) and elevated (700–800 ppm) CO2 concentration. In C3 leaves, the 12CO2 emission in the light (Rd) was low at ambient CO2 and was further quenched in elevated CO2, when it was often only 20–30% of the 12CO2 emission in the dark, interpreted as the mitochondrial respiration in the dark (Rn). Rn was also reduced in elevated CO2. At low CO2, Rd was often 70–80% of Rn, and a burst of 12CO2 was observed on darkening leaves of Mentha sativa and Phragmites australis after exposure for 4 min to 13CO2 in the light. The burst was partially removed at low oxygen and was never observed in C4 leaves, suggesting that it may be caused by incomplete labelling of the photorespiratory pool at low CO2. This pool may be low in sclerophyllous leaves, as in Quercus ilex where no burst was observed. Rd was inversely associated with photosynthesis, suggesting that the Rd/Rn ratio reflects the refixation of respiratory CO2 by photosynthesizing leaves rather than the inhibition of mitochondrial respiration in the light, and that CO2 produced by mitochondrial respiration in the light is mostly emitted at low CO2, and mostly refixed at elevated CO2.. In the leaves of the C4 species Zea mays, the 12CO2 emission in the light also remained low at low CO2, suggesting efficient CO2 refixation associated with sustained photosynthesis in non‐photorespiratory conditions. However, Rn was inhibited in CO2‐free air, and the velocity of 12CO2 emission after darkening was inversely associated with the CO2 concentration. The emission may be modulated by the presence of post‐illumination CO2 uptake deriving from temporary imbalance between C3 and C4 metabolism. These experiments suggest that this uptake lasts longer at low CO2 and that the imbalance is persistent once it has been generated by exposure to low CO2.
10.1093/jxb/erg187
Keywords: 13C labelling; C3 versus C4 metabolism; mitochondrial respiration; photorespiration; photosynthesis

The ability of abaxial and adaxial epidermis of sun and shade leaves to attenuate UV-A and UV-B radiation in relation to the UV absorbing capacity of the whole leaf methanolic extracts - Liakoura, Vally; Bornman, Janet F.; Karabourniotis, George (Physiologia Plantarum, 2003)
The UV-absorbing capacity (measured as A310 cm−2 and A365 cm−2 or AUVR cm−2) of the shade leaves of four representative evergreen sclerophylls of the Mediterranean region (Quercus coccifera, Q. ilex, Arbutus andrachne and A. unedo) was considerably lower than the corresponding one of sun leaves of the same species. However, fibre optic microprobe measurements showed that adaxial as well as abaxial epidermis of shade leaves of all examined plants, except abaxial epidermis of A. andrachne, were almost as effective as the corresponding ones of the sun leaves in screening out most of the incident UV-B radiation. There is probably a threshold, under which the concentration of the UV-B absorbing compounds in the protective tissues is not furthermore reduced, in spite of the low levels of the stress factor (UV-B radiation) in the environment. On the other hand, the ability of both abaxial and adaxial epidermis to attenuate UV-A radiation, except of adaxial leaf epidermis of Quercus species, depended on the UV absorbing capacity of the whole-leaf extracts, with different correlation patterns between the two Quercus species and the two Arbutus species. This could be explained by the fact that shade leaves showed not only quantitative, but also qualitative differences (higher A310/A365 ratio) in the absorbance of their methanolic extracts compared to these of sun leaves. The results of the present study showed that we should not always correlate the depth of penetration of UV radiation into sun and shade leaves according to the corresponding UV absorbing capacity of the whole leaf methanolic extracts, without taking into account all the anatomical, developmental and biochemical (such as different composition and distribution of the UV-absorbing compounds among the different protective tissues) peculiarities of the leaves of each species.
The following values have no corresponding Zotero field: publisher: Munksgaard International Publishers
Keywords: abaxial epidermis; adaxial epidermis; Sun and shade leaves; uv absorbing compounds (voyant); UV-A and UV-B radiation

Agrarian elites and economic growth in nineteenth-century Portugal: The example of the Alentejo in the Liberal era (1850-1910) - Fonseca, Helder Adegar (Social History, 2003)
The Alentejo is a southern Portuguese region which is generally recognized for the social and economic importance of the latifúndio system and for its economic backwardness, phenomena which are usually associated with the existence of a regional elite of the traditional type. This article seeks to review this question by examining the action of the economic elite which operated in the region during the second half of the nineteenth century, when modern capitalism was just beginning to develop in Portugal and Liberal institutions were being established. How this sociologically renewed and plural elite group conducted its private business dealings is described, and investment strategies and sources of financing are examined, as well as the management of farm businesses. Three aspects are highlighted here: the varied nature of investments, although over the long term there was an increase in the acquisition of land; investment carried out at the cost of growing indebtedness to the regional banks, the modern financial institutions which the elite helped to set up; and the high degree of involvement of land-owners in the running of large estates, which were marked by a trend towards division into smaller units, moves towards productive diversification, and the drive for technical progress and the modernization of rural buildings. Examined as a whole, this scenario suggests that the new economic elite which emerged with the triumph and development of Portuguese Liberalism in the nineteenth century was not a force for conservatism in the regional economy.
doi: 10.1080/0307102032000082507doi: 10.1080/0307102032000082507The following values have no corresponding Zotero field: publisher: Routledge
Keywords: Alentejo; economic elite; land acquisition; large estates (voyant); XIX century

Agrarian elites and economic growth in nineteenth-century Portugal: The example of the Alentejo in the Liberal era (1850-1910) - Fonseca, Helder Adegar (Social History, 2003)
The Alentejo is a southern Portuguese region which is generally recognized for the social and economic importance of the latifúndio system and for its economic backwardness, phenomena which are usually associated with the existence of a regional elite of the traditional type. This article seeks to review this question by examining the action of the economic elite which operated in the region during the second half of the nineteenth century, when modern capitalism was just beginning to develop in Portugal and Liberal institutions were being established. How this sociologically renewed and plural elite group conducted its private business dealings is described, and investment strategies and sources of financing are examined, as well as the management of farm businesses. Three aspects are highlighted here: the varied nature of investments, although over the long term there was an increase in the acquisition of land; investment carried out at the cost of growing indebtedness to the regional banks, the modern financial institutions which the elite helped to set up; and the high degree of involvement of land-owners in the running of large estates, which were marked by a trend towards division into smaller units, moves towards productive diversification, and the drive for technical progress and the modernization of rural buildings. Examined as a whole, this scenario suggests that the new economic elite which emerged with the triumph and development of Portuguese Liberalism in the nineteenth century was not a force for conservatism in the regional economy.
doi: 10.1080/0307102032000082507
Keywords: Alentejo; economic elite; land acquisition; large estates (voyant); XIX century

Assessment of nutritional status and trace element contamination of holm oak woodlands through analyses of leaves and surrounding soils. - De Nicola, F; Maisto, G; Alfani, a (The Science of the total environment, 2003)
The nutritional status and trace element contamination of holm oak woodlands in Vesuvius National Park were assessed by analyses of Quercus ilex L. leaves and surrounding soils. The concentrations of Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, V and Zn were measured in 1-year-old leaves, and in the soils at 0-5 and 15-20 cm depths. The potentially available concentrations were also measured for the soils. The leaf element concentrations were similar to the Q. ilex chemical fingerprint, thus indicating a good nutritional status and the absence of short-term trace element depositions. Total K and V were more abundant in the deep soil layers than in the surface ones, whereas Cd and Pb showed higher values in the surface soils. This suggests that long-term soil accumulations of Cd and Pb are due to atmospheric input. The soil availabilities of Cd, Pb and Zn were high, and Cr availability was very low. A correlation between the available concentrations in the deep soil layers and leaf concentrations was found only for Zn.
Keywords: Available soil elements; Micro and macro elements; Quercus ilex L.leaves; Total soil elements; Vesuvius National Park

Assessment of nutritional status and trace element contamination of holm oak woodlands through analyses of leaves and surrounding soils. - De Nicola, F.; Maisto, G.; Alfani, A. (The Science of the total environment, 2003)
The nutritional status and trace element contamination of holm oak woodlands in Vesuvius National Park were assessed by analyses of Quercus ilex L. leaves and surrounding soils. The concentrations of Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, V and Zn were measured in 1-year-old leaves, and in the soils at 0-5 and 15-20 cm depths. The potentially available concentrations were also measured for the soils. The leaf element concentrations were similar to the Q. ilex chemical fingerprint, thus indicating a good nutritional status and the absence of short-term trace element depositions. Total K and V were more abundant in the deep soil layers than in the surface ones, whereas Cd and Pb showed higher values in the surface soils. This suggests that long-term soil accumulations of Cd and Pb are due to atmospheric input. The soil availabilities of Cd, Pb and Zn were high, and Cr availability was very low. A correlation between the available concentrations in the deep soil layers and leaf concentrations was found only for Zn.
The following values have no corresponding Zotero field: accession-num: 12826392
Keywords: Available soil elements; Micro and macro elements; Quercus ilex L.leaves; Total soil elements; Vesuvius National Park

Botanic analysis of Livia's villa painted flora (Prima Porta, Roma) - Caneva, G; Bohuny, L (JOURNAL OF CULTURAL HERITAGE, 2003)
The frescoes of Livia's villa at Prima Porta, Rome, are the most famous representations of Roman gardens. The painted flora is analyzed from the scientific viewpoint and previous identifications are critically discussed. Here, 24 different species are described, giving information on the taxonomic, and phytogeographic position. Most of them belong to the spontaneous elements present in the Mediterranean forests, maquis and grasses of Southern Italy, such as Arbutus unedo, Laurus nobilis, Nerium oleander, Quercus ilex, Quercus robur gr., Comas mas, Myrtus communis, Phyllitis scolopendrium, Viola reichenbachiana, Chrysanthemum coronarium, Anthemis cotula, or widely cultivated, such as Cupressus sempervirens. cydonia oblonga, Pinus pinea, Punica granatum, Papaver somniferum, Rosa centifolia, Phoenix dactylifera. A symbolistic purpose of the pictures is also clearly evident. (C) 2003 Editions scientifiques et medicales Elsevier SAS. All rights reserved.
Keywords: botanical iconography; painted flora; Roman frescoes; Roman gardens

Botryosphaeria and Related Taxa Causing Oak Canker in Southwestern Spain - SÁNCHEZ, M E; Venegas, J; Romero, M A; Phillips, A J L; TRAPERO, A (Plant Disease, 2003)
ABSTRACT Although root disease caused by Phytophthora cinnamomi is considered to be the most frequent and damaging disease associated with Quercus spp. decline in southwestern Spain, cankers commonly are observed on branches of declining Mediterranean Quercus spp. in this region. In surveys carried out in eight declining Quercus forests, strips of necrotic inner bark were common on diseased branches. Botryosphaeria stevensii, B. dothidea, and Diplodia sarmentorum consistently were isolated from these branches. Isolates of all three species caused cankers when inoculated onto excised Quercus branches. Inoculations on healthy branches in the field also induced canker development, but only B. stevensii caused lesions that girdled and killed the branches. The optimum temperature for in vitro growth of B. stevensii and B. dothidea was above 25°C, with slow growth at 35°C. In contrast, D. sarmentorum had an optimum temperature for growth of about 21°C, and did not grow at 35°C. The common occurrence and wide distribution of these pathogens, their association with cankers, and their ability to infect Quercus spp. suggest that they may contribute to the Quercus spp. decline in southwestern Spain.
doi: 10.1094/PDIS.2003.87.12.1515
Keywords: Botryosphaeria ribis; diplodia mutila; Fusicoccum aesculi; Otthia spi- raeae; Quercus ilex; Quercus suber

Breeding ecology of Algerian woodchat shrikes Lanius senator: low breeding success - Brahimi, Z.; Dziri, H.; Benyacoub, S.; Chabi, Y.; Banbura, J. (FOLIA ZOOLOGICA, 2003)
Breeding ecology of woodchat shrikes Lanius senator was investigated in the EL-Kala National Park in North-East Algeria (36degrees53'N; 8degrees30'E) in 1998-1999. Quercus suber was the tree species most frequently used as support for nests, which were constructed at a mean height of 5 m. First eggs in clutches were laid 7 May, and clutch size was 4.9. Approximately 42% eggs gave fledglings. Clutch size declined during the course of the breeding season but fledgling success did not. Fledging success was positively correlated with per clutch mean egg length and the height of the nest location above ground. We suggest that the major selective pressures that shape the life history of Algerian woodchat shrikes are relatively heave predation and poor food availability.
The following values have no corresponding Zotero field: pub-location: KVETNA 8, BRNO 603 65, CZECH REPUBLIC publisher: INST VERTEBRATE BIOLOGY AS CR
Keywords: biology; clutch size; egg size; fledging success; nesting; nestling growth; North Africa; passerine

Can the Argentine ant (Linepithema humile Mayr) replace native ants in myrmecochory? - Gómez, Crisanto; Oliveras, Jordi (Acta Oecologica, 2003)
We analyse the inﬂuence of the Argentine ant (Linepithema humile Mayr) on the seed dispersal process of the myrmecochorous plants Euphorbia characias, E. biumbellata, Genista linifolia, G. triﬂora, G. monspessulana and Sarothamnus arboreus. The observations were made in two study plots of Mediterranean cork-oak secondary forest (invaded and non-invaded by L. humile). The presence of L. humile implies the displacement of all native ant species that disperse seeds. Seed transports in the non-invaded zone were carried out by eight ant species. In the invaded zone, L. humile workers removed and transported seeds to the nest. In vertebrate exclusion trials, we observed the same level of seed removal in the invaded and non-invaded zones. Two ﬁndings could explain this result. Although mean time to seed localization was higher for native ants (431.7 s) than that for L. humile (150.5 s), the mean proportion of seeds transported after being detected was higher (50.1%) in non-invaded than in invaded (16.8%) zones. The proportion of seeds removed and transported into an ant nest after an ant-seed interaction had dramatically reduced from non-invaded (41.9%) to invaded (7.4%) zones. The levels of seed dispersal by ants found prior to invasion are unlikely to be maintained in invaded zones. However, total replacement of seed dispersal function is possible if contact iteration ﬁnally offers similar levels or quantities of seeds reaching the nests. The results obtained conﬁrm that the Argentine ant invasion may affect myrmecochory dramatically in the Mediterranean biome.
Keywords: ant-plant mutualism; Argentine ant; Biological invasion; Linepithema humile; myrmecochory; seed dispersal

Characterization of semi-extensive goat production systems in southern Spain - Castel, J. M.; Mena, Y.; Delgado-Pertinez, M.; Camunez, J.; Basulto, J.; Caravaca, F.; Guzman-Guerrero, J. L.; Alcalde, M. J. (SMALL RUMINANT RESEARCH, 2003)
This study attempts to describe the semi-extensive goat fanning sector in Andalusia (south of Spain) and to establish characteristics. Eighty-nine goat farmers were surveyed in three areas of this region. The survey examined all aspects of the systems, from socio-economy to management. A multivariate analysis (multiple correspondence and cluster) was used to determine the different farm characteristics. Most of the goat farms studied are single-worker or family managed. The farmers lack training and are elderly, so that continuity of the activity is not assured, although newcomers are usually young. All the farms have some area in ownership, although the farms most specialized in dairy goat products are the smallest in both ownership and total area. The roads are generally in good condition, except on farms with little land, situated in areas of the sierra. Machine-milking installations, closely related to the presence of infrastructures and of goats with a dairy tendency, are generally lacking, (this aspect is improving day by day). Artificial nursing is less generalized than machine-milking. Farms specializing in milk production, whose main activity is dairy goat farming, have dairy specialized breed or crossbred (milk and meat) goats. Feeding depends largely on grazing, with little area being cultivated to produce feed for the goats. Little distinction is made for the production level. Olive or acorn tree branches (Quercus ilex spp.) are used as feedstuff, depending on the types of tree predominating in the area. Five farm types were established, the differences depending on 14 variables of socio-economic aspects, level of production, infrastructure and installations, and feeding. Generated information from this study entails an advance into knowledge of goat farming systems in the Mediterranean area (where little information is generated). The relevance of this study is important since Andalusia has 40% of goats in Spain that produce more than half of the total goat milk in the country, which points out the socio-economical importance for most depressed areas in the region. This work supposes previous steps for improving the semi-extensive goat farming sector. From a methodological point of view, the discussion on variable types and utility establishes farm type characteristics. (C) 2002 Elsevier Science 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: characterization methods; goat systems; semi-extensive farming; southern Spain

Characterization of semi-extensive goat production systems in southern Spain - Castel, J M; Mena, Y; Delgado-Pertinez, M; Camunez, J; Basulto, J; Caravaca, F; Guzman-Guerrero, J L; Alcalde, M J (SMALL RUMINANT RESEARCH, 2003)
This study attempts to describe the semi-extensive goat fanning sector in Andalusia (south of Spain) and to establish characteristics. Eighty-nine goat farmers were surveyed in three areas of this region. The survey examined all aspects of the systems, from socio-economy to management. A multivariate analysis (multiple correspondence and cluster) was used to determine the different farm characteristics. Most of the goat farms studied are single-worker or family managed. The farmers lack training and are elderly, so that continuity of the activity is not assured, although newcomers are usually young. All the farms have some area in ownership, although the farms most specialized in dairy goat products are the smallest in both ownership and total area. The roads are generally in good condition, except on farms with little land, situated in areas of the sierra. Machine-milking installations, closely related to the presence of infrastructures and of goats with a dairy tendency, are generally lacking, (this aspect is improving day by day). Artificial nursing is less generalized than machine-milking. Farms specializing in milk production, whose main activity is dairy goat farming, have dairy specialized breed or crossbred (milk and meat) goats. Feeding depends largely on grazing, with little area being cultivated to produce feed for the goats. Little distinction is made for the production level. Olive or acorn tree branches (Quercus ilex spp.) are used as feedstuff, depending on the types of tree predominating in the area. Five farm types were established, the differences depending on 14 variables of socio-economic aspects, level of production, infrastructure and installations, and feeding. Generated information from this study entails an advance into knowledge of goat farming systems in the Mediterranean area (where little information is generated). The relevance of this study is important since Andalusia has 40% of goats in Spain that produce more than half of the total goat milk in the country, which points out the socio-economical importance for most depressed areas in the region. This work supposes previous steps for improving the semi-extensive goat farming sector. From a methodological point of view, the discussion on variable types and utility establishes farm type characteristics. (C) 2002 Elsevier Science B.V. All rights reserved.
Keywords: characterization methods; goat systems; semi-extensive farming; southern Spain

The chemistry of precipitation, throughfall and stemflow in two holm oak (Quercus ilex L.) forests under a contrasted pollution environment in NE Spain. - Rodrigo, a; Avila, a; Rodà, F (The Science of the total environment, 2003)
Atmospheric deposition was studied through measurements of bulk deposition, throughfall and stemflow at two sites of contrasted exposure to pollution in the Montseny mountains (Northeastern Spain). To explore the contribution of local or distant sources at both sites, concentration data and precipitation amounts (log transformed) for both bulk deposition and net throughfall were fitted by linear regression. These models indicated the more important contribution of washout scavenging processes and dry deposition at the pollution exposed site. This is relevant in the context of Mediterranean holm oak forests: up to now, most of the studies have been conducted in protected remote sites and were little representative of the fluxes in forests close to industrial activity, traffic, agriculture and residential areas.
Keywords: bulk deposition; Dry deposition; Holm oak forest; Leaching; N uptake; throughfall

The chemistry of precipitation, throughfall and stemflow in two holm oak (Quercus ilex L.) forests under a contrasted pollution environment in NE Spain. - Rodrigo, a; Avila, A.; Roda, F. (The Science of the total environment, 2003)
Atmospheric deposition was studied through measurements of bulk deposition, throughfall and stemflow at two sites of contrasted exposure to pollution in the Montseny mountains (Northeastern Spain). To explore the contribution of local or distant sources at both sites, concentration data and precipitation amounts (log transformed) for both bulk deposition and net throughfall were fitted by linear regression. These models indicated the more important contribution of washout scavenging processes and dry deposition at the pollution exposed site. This is relevant in the context of Mediterranean holm oak forests: up to now, most of the studies have been conducted in protected remote sites and were little representative of the fluxes in forests close to industrial activity, traffic, agriculture and residential areas.
The following values have no corresponding Zotero field: accession-num: 12670768
Keywords: bulk deposition; Dry deposition; Holm oak forest; Leaching; N uptake; throughfall

Comparison between ethanol and hexane for oil extraction from Quercus suber L. fruits - Ferreira-Dias, Suzana; Valente, Dina G; Abreu, José M F (Grasas y Aceites, 2003)
The aim of this study was to (i) evaluate the feasibility of replacing n -hexane with ethanol for the extraction of oil from Quercus suber fruits and (ii) optimize, at lab scale, sample preparation and extraction time for both solvents used ( n -hexane vs . anhydrous ethanol). For both solvents, the effect of the conditioning process on extraction yield was evaluated. Therefore, a full factorial design was used as a function of four variables: dehulling (with vs . without husks), and thermal treatment of the crushed material (40ºC vs . 75ºC), at different times (5 min vs . 120 min) and pressures (10 kPa vs. 100 kPa). Higher oil yields were obtained with n -hexane when dehulled fruits were conditioned under atmospheric pressure. Better yields were obtained with n -hexane, when dehulled material was treated at 75ºC for 90 min. Ethanol was not adequate for oil extraction from Quercus fruits, since other materials rather than oil were also extracted.
Keywords: acorns; Ethanol; Extraction; Hexane; Oil; Quercus

Comparison between ethanol and hexane for oil extraction from Quercus suber L. fruits - Ferreira-Dias, Suzana; Valente, Dina G.; Abreu, José M. F. (Grasas y Aceites, 2003)
The aim of this study was to (i) evaluate the feasibility of replacing n -hexane with ethanol for the extraction of oil from Quercus suber fruits and (ii) optimize, at lab scale, sample preparation and extraction time for both solvents used ( n -hexane vs . anhydrous ethanol). For both solvents, the effect of the conditioning process on extraction yield was evaluated. Therefore, a full factorial design was used as a function of four variables: dehulling (with vs . without husks), and thermal treatment of the crushed material (40ºC vs . 75ºC), at different times (5 min vs . 120 min) and pressures (10 kPa vs. 100 kPa). Higher oil yields were obtained with n -hexane when dehulled fruits were conditioned under atmospheric pressure. Better yields were obtained with n -hexane, when dehulled material was treated at 75ºC for 90 min. Ethanol was not adequate for oil extraction from Quercus fruits, since other materials rather than oil were also extracted.
Keywords: acorns; Ethanol; Extraction; Hexane; Oil; Quercus

Comparison of the post-fire dynamics of the ectomycorrhizal community in two Quercus ilex stands in Northern Spain - CLAVERÍA, V; DE MIGUEL, A M; DE ROMÁN, M (Publ. Bio. Univ. Navarra, Ser. Bot.,, 2003)
A comparative study of the post-fire recolonization of ectomycorrhizae in two evergreen oak stands (Quercus ilex L. subsp. ballota (Desf.) Samp.) in Nazar and San Cristóbal (Navarra, Spain) has been carried out. In 1993 a stand in Nazar burnt, but it was not until 1998 that the study started. On the contrary, the study in San Cristóbal started immediately after the stand had caught fire in 2000. Therefore we have been able to compare the regeneration in both stands and the species composition five years after the fire and immediately after the fire, as well as the differences in ectomycorrhizal colonization and abundance of morphotypes between the burnt plots and areas which remained undisturbed in both forests, thus acting as control plots. In both sites the percentage of ectomycorrhizal colonization tended to be lower after the wildfire. In San Cristóbal, in the burnt site there was a lower abundance of morphotypes compared to the control site. However, in Nazar, five years after the fire, we did not find any significant change in species richness, but rather a shift in the abundance of each morphotype when comparing the burnt and the control plots. There are some species of mycorrhizal fungi which seem to be particularly adapted to fire, such as Type 1 in San Cristóbal and Cenococcum geophilum in Nazar. Sphaerosporella brunnea, a pioneer species considered to be especially suitable for the colonization of burnt substrates, was only found in Nazar.
Keywords: Ectomycorrhizae; fire; Quercus ilex; succession

Comparison of the post-fire dynamics of the ectomycorrhizal community in two Quercus ilex stands in Northern Spain - CLAVERÍA, V.; DE MIGUEL, A. M.; DE ROMÁN, M. (Publ. Bio. Univ. Navarra, Ser. Bot.,, 2003)
A comparative study of the post-fire recolonization of ectomycorrhizae in two evergreen oak stands (Quercus ilex L. subsp. ballota (Desf.) Samp.) in Nazar and San Cristóbal (Navarra, Spain) has been carried out. In 1993 a stand in Nazar burnt, but it was not until 1998 that the study started. On the contrary, the study in San Cristóbal started immediately after the stand had caught fire in 2000. Therefore we have been able to compare the regeneration in both stands and the species composition five years after the fire and immediately after the fire, as well as the differences in ectomycorrhizal colonization and abundance of morphotypes between the burnt plots and areas which remained undisturbed in both forests, thus acting as control plots. In both sites the percentage of ectomycorrhizal colonization tended to be lower after the wildfire. In San Cristóbal, in the burnt site there was a lower abundance of morphotypes compared to the control site. However, in Nazar, five years after the fire, we did not find any significant change in species richness, but rather a shift in the abundance of each morphotype when comparing the burnt and the control plots. There are some species of mycorrhizal fungi which seem to be particularly adapted to fire, such as Type 1 in San Cristóbal and Cenococcum geophilum in Nazar. Sphaerosporella brunnea, a pioneer species considered to be especially suitable for the colonization of burnt substrates, was only found in Nazar.
Keywords: Ectomycorrhizae; fire; Quercus ilex; succession

The composition of the diet of red deer (Cervus elaphus) in a Mediterranean environment: a case of summer nutritional constraint? - Bugalho, Miguel N; Milne, John a (Forest Ecology and Management, 2003)
The composition of the diet of red deer (Cervus elaphus) in a Mediterranean environment, in southern Portugal, was estimated during summer 1995–1997 using n-alkane analysis. Standing crop of herbage layer biomass was estimated between June and September 1995–1997 using the clipping quadrat method. There was a large variability between years in the availability of the herbage layer biomass. Biomass was three fold greater and availability of legumes higher in a wet than in a dry year. Live green material was available in the herbage layer in June, but not thereafter, even during a wet year. Red deer ingested a higher proportion of browse in summer during drier years (0.83–0.89) than during a wet year (0.47). In the drier years, the herbage layer was replaced in the diet by browse species that were uneaten in the wet year. Contrary to Atlantic environments, where red deer include a large proportion of browse in their diets during winter, summer is likely to be a season of nutritional constraint for red deer inhabiting Mediterranean environments
Keywords: browse; cervus elaphus; diet composition; Mediterranean

The composition of the diet of red deer (Cervus elaphus) in a Mediterranean environment: a case of summer nutritional constraint? - Bugalho, Miguel N.; Milne, John a (Forest Ecology and Management, 2003)
The composition of the diet of red deer (Cervus elaphus) in a Mediterranean environment, in southern Portugal, was estimated during summer 1995–1997 using n-alkane analysis. Standing crop of herbage layer biomass was estimated between June and September 1995–1997 using the clipping quadrat method. There was a large variability between years in the availability of the herbage layer biomass. Biomass was three fold greater and availability of legumes higher in a wet than in a dry year. Live green material was available in the herbage layer in June, but not thereafter, even during a wet year. Red deer ingested a higher proportion of browse in summer during drier years (0.83–0.89) than during a wet year (0.47). In the drier years, the herbage layer was replaced in the diet by browse species that were uneaten in the wet year. Contrary to Atlantic environments, where red deer include a large proportion of browse in their diets during winter, summer is likely to be a season of nutritional constraint for red deer inhabiting Mediterranean environments
Keywords: browse; cervus elaphus; diet composition; Mediterranean

Decline in photosynthetic nitrogen use efficiency with leaf age and nitrogen resorption as determinants of leaf life span - Escudero, A.; Mediavilla, S. (Journal of Ecology, 2003)
* 1Cost-benefit models predict that leaf life span depends on its initial photosynthetic rate and construction cost and on the rate of decline in photosynthesis with age. Leaf gas exchange rates and N contents were measured in nine woody evergreen Mediterranean species with different leaf life spans to determine the effects of leaf ageing on photosynthetic N use efficiency (PNUE). N costs of leaf construction were assumed to be in part dependent on N resorption from senescing leaves. * 2Leaf ageing had significant negative effects on photosynthetic rates per unit leaf area. As N content per unit leaf area did not decline until the end of leaf life, PNUE also decreased with age. PNUE generally declined faster in species with a shorter leaf life span. There were no significant interspecific differences in maximum CO2 assimilation rates per unit leaf area and in N resorption that could be related to differences in leaf life span. * 3As PNUE decreases with leaf age, shedding of the older leaves and retranslocation of N to the current year's leaf biomass would result in an increase in the mean instantaneous efficiency of use of the N retranslocated. However, total CO2 assimilation can be improved by such shedding only when the increase in the efficiency of use of the remobilized N compensates for the remaining N lost in the shed leaves. * 4The photosynthesis of the old leaf cohorts exceeded the increase in photosynthesis that would be obtained from the N retranslocated to the younger leaves, given the observed efficiencies of N resorption. The retention of old leaves thus resulted in a higher whole-canopy CO2 assimilation, despite their low PNUE.
The following values have no corresponding Zotero field: publisher: Blackwell Science Ltd
Keywords: leaf life span; N resorption; photosynthetic nitrogen use efficiency; Pinus spp.; Quercus spp

Decline in photosynthetic nitrogen use efficiency with leaf age and nitrogen resorption as determinants of leaf life span - Escudero, a; Mediavilla, S (Journal of Ecology, 2003)
* 1Cost-benefit models predict that leaf life span depends on its initial photosynthetic rate and construction cost and on the rate of decline in photosynthesis with age. Leaf gas exchange rates and N contents were measured in nine woody evergreen Mediterranean species with different leaf life spans to determine the effects of leaf ageing on photosynthetic N use efficiency (PNUE). N costs of leaf construction were assumed to be in part dependent on N resorption from senescing leaves. * 2Leaf ageing had significant negative effects on photosynthetic rates per unit leaf area. As N content per unit leaf area did not decline until the end of leaf life, PNUE also decreased with age. PNUE generally declined faster in species with a shorter leaf life span. There were no significant interspecific differences in maximum CO2 assimilation rates per unit leaf area and in N resorption that could be related to differences in leaf life span. * 3As PNUE decreases with leaf age, shedding of the older leaves and retranslocation of N to the current year's leaf biomass would result in an increase in the mean instantaneous efficiency of use of the N retranslocated. However, total CO2 assimilation can be improved by such shedding only when the increase in the efficiency of use of the remobilized N compensates for the remaining N lost in the shed leaves. * 4The photosynthesis of the old leaf cohorts exceeded the increase in photosynthesis that would be obtained from the N retranslocated to the younger leaves, given the observed efficiencies of N resorption. The retention of old leaves thus resulted in a higher whole-canopy CO2 assimilation, despite their low PNUE.
Keywords: leaf life span; N resorption; photosynthetic nitrogen use efficiency; Pinus spp.; Quercus spp

Degradation of vanillic acid and production of guaiacol by microorganisms isolated from cork samples - Álvarez-Rodríguez, María Luisa; Belloch, Carmela; Villa, Mercedes; Uruburu, Federico; Larriba, Germán; Coque, Juan-José R (FEMS Microbiology Letters, 2003)
The presence of guaiacol in cork stoppers is responsible for some cases of cork taint causing unpleasant alterations to wine. We have performed a characterization of the cork-associated microbiota by isolating 55 different microorganisms: eight yeast, 14 filamentous fungi or molds, 13 actinomycetes and 20 non-filamentous bacteria. A screening for degradation of vanillic acid and guaiacol production showed that none of the filamentous fungi could achieve any of these processes. By contrast, five of the eight yeast strains isolated were able to degrade vanillic acid, although it was not converted to guaiacol. Guaiacol production was only detected in four bacterial strains: one isolate of Bacillus subtilis and three actinomycetes, Streptomyces sp. A3, Streptomyces sp. A5 and Streptomyces sp. A13, were able to accumulate this compound in both liquid media and cultures over cork. These results suggest that guaiacol-mediated cork taint should be attributed to the degradative action of vanillic acid by bacterial strains growing on cork.
Keywords: Cork taint; Guaiacol; Vanillic acid; Wine aroma

Degradation of vanillic acid and production of guaiacol by microorganisms isolated from cork samples - Álvarez-Rodríguez, María Luisa; Belloch, Carmela; Villa, Mercedes; Uruburu, Federico; Larriba, Germán; Coque, Juan-José R. (FEMS Microbiology Letters, 2003)
The presence of guaiacol in cork stoppers is responsible for some cases of cork taint causing unpleasant alterations to wine. We have performed a characterization of the cork-associated microbiota by isolating 55 different microorganisms: eight yeast, 14 filamentous fungi or molds, 13 actinomycetes and 20 non-filamentous bacteria. A screening for degradation of vanillic acid and guaiacol production showed that none of the filamentous fungi could achieve any of these processes. By contrast, five of the eight yeast strains isolated were able to degrade vanillic acid, although it was not converted to guaiacol. Guaiacol production was only detected in four bacterial strains: one isolate of Bacillus subtilis and three actinomycetes, Streptomyces sp. A3, Streptomyces sp. A5 and Streptomyces sp. A13, were able to accumulate this compound in both liquid media and cultures over cork. These results suggest that guaiacol-mediated cork taint should be attributed to the degradative action of vanillic acid by bacterial strains growing on cork.
The following values have no corresponding Zotero field: publisher: Blackwell Publishing Ltd
Keywords: Cork taint; Guaiacol; Vanillic acid; Wine aroma

Diplopyrone, a New Phytotoxic Tetrahydropyranpyran-2-one Produced by Diplodia mutila, a Fungus Pathogen of Cork Oak - Evidente, Antonio; Maddau, Lucia; Spanu, Emanuela; Franceschini, Antonio; Lazzaroni, Silvia; Motta, Andrea (Journal of Natural Products, 2003)
A new phytotoxic monosubstituted tetrahydropyranpyran-2-one, named diplopyrone (1), was isolated from the liquid culture filtrates of Diplodia mutila, a plant pathogenic fungus causing a form of canker disease of cork oak (Quercus suber). Diplopyrone was characterized, using spectroscopic and chemical methods, as 6-[(1S)-1-hydroxyethyl]-2,4a,6,8a-tetrahydropyran[3,2-b]pyran-2-one. The absolute stereochemistry of the chiral secondary hydroxylated carbon (C-9), determined by application of Mosher's method, proved to be S. Diplopyrone assayed at a 0.01?0.1 mg/mL concentration range caused necrosis and wilting on cork oak cuttings. On a nonhost plant, tomato, diplopyrone caused brown discoloration or stewing on the stem.
Keywords: Phytopathogenic fungi; Phytotoxins; relative and/or absolute configuration; structure–activity relationships

Diplopyrone, a New Phytotoxic Tetrahydropyranpyran-2-one Produced by Diplodia mutila, a Fungus Pathogen of Cork Oak - Evidente, Antonio; Maddau, Lucia; Spanu, Emanuela; Franceschini, Antonio; Lazzaroni, Silvia; Motta, Andrea (Journal of Natural Products, 2003)
A new phytotoxic monosubstituted tetrahydropyranpyran-2-one, named diplopyrone (1), was isolated from the liquid culture filtrates of Diplodia mutila, a plant pathogenic fungus causing a form of canker disease of cork oak (Quercus suber). Diplopyrone was characterized, using spectroscopic and chemical methods, as 6-[(1S)-1-hydroxyethyl]-2,4a,6,8a-tetrahydropyran[3,2-b]pyran-2-one. The absolute stereochemistry of the chiral secondary hydroxylated carbon (C-9), determined by application of Mosher's method, proved to be S. Diplopyrone assayed at a 0.01?0.1 mg/mL concentration range caused necrosis and wilting on cork oak cuttings. On a nonhost plant, tomato, diplopyrone caused brown discoloration or stewing on the stem.
The following values have no corresponding Zotero field: publisher: American Chemical Society accession-num: 12608876
Keywords: Phytopathogenic fungi; Phytotoxins; relative and/or absolute configuration; structure–activity relationships

Diversidad biológica y sostenibilidad ecológica y económica de los sistemas adehesados - Díaz, M.; Pulido, F. J.; MARAÑON, T. (Ecosistemas, 2003)
Los bosques mediterráneos son sistemas naturales con una elevada diversidad biológica, que tiende a aumentar cuando son explotados para formar dehesas arboladas. Dentro de este sistema de explotación, la riqueza de especies varía en función de los efectos del manejo humano sobre la estructura de la vegetación, tanto subarbórea (presencia de cultivos de cereal o manchas de matorral) como arbórea (densidad de árboles). Estas tendencias se observan en varios grupos de organismos y para un amplio rango de escalas espaciales, y parecen deberse a la íntima coexistencia espacial en las dehesas de elementos faunísticos y florísticos forestales, asociados al arbolado y al matorral, y de elementos propios de zonas abiertas, asociados a los pastizales y cultivos sobre los que crecen los árboles. La coexistencia a escala de finca de distintos usos, así como la coexistencia de las dehesas y otros hábitats a escala regional, contribuyen al mantenimiento de especies adicionales. No obstante, se requieren perturbaciones como el fuego o el uso humano, que serían las causas últimas de esta diversidad. La diversidad biológica de las dehesas podría contribuir a su sostenibilidad económica si èsta es valorada adecuadamente por la sociedad. Además, se requerirían medidas adicionales que garantizasen situaciones temporales de menor diversidad pero indispensables para la regeneración del arbolado y la sostenibilidad ecológica de este peculiar sistema de explotación.

Diversidad biológica y sostenibilidad ecológica y económica de los sistemas adehesados - Diaz, M; Pulido, F J; MARAÑÓN, T (Ecosistemas, 2003)
Los bosques mediterráneos son sistemas naturales con una elevada diversidad biológica, que tiende a aumentar cuando son explotados para formar dehesas arboladas. Dentro de este sistema de explotación, la riqueza de especies varía en función de los efectos del manejo humano sobre la estructura de la vegetación, tanto subarbórea (presencia de cultivos de cereal o manchas de matorral) como arbórea (densidad de árboles). Estas tendencias se observan en varios grupos de organismos y para un amplio rango de escalas espaciales, y parecen deberse a la íntima coexistencia espacial en las dehesas de elementos faunísticos y florísticos forestales, asociados al arbolado y al matorral, y de elementos propios de zonas abiertas, asociados a los pastizales y cultivos sobre los que crecen los árboles. La coexistencia a escala de finca de distintos usos, así como la coexistencia de las dehesas y otros hábitats a escala regional, contribuyen al mantenimiento de especies adicionales. No obstante, se requieren perturbaciones como el fuego o el uso humano, que serían las causas últimas de esta diversidad. La diversidad biológica de las dehesas podría contribuir a su sostenibilidad económica si èsta es valorada adecuadamente por la sociedad. Además, se requerirían medidas adicionales que garantizasen situaciones temporales de menor diversidad pero indispensables para la regeneración del arbolado y la sostenibilidad ecológica de este peculiar sistema de explotación.

Drought resistance of 2-year-old saplings of Mediterranean forest trees in the field: relations between water relations, hydraulics and productivity - Gullo, M A Lo; Salleo, S; Rosso, R; Trifilo, P (Plant and soil, 2003)
Drought resistance was examined for 2-year-old saplings of Ceratonia siliqua L., Olea oleaster Hoffmgg. et Link., Quercus suber L. and Q. pubescens Willd. growing in the ﬁeld in Sicily, with the aim of testing their possible use in the reforestation of degraded areas. To this purpose, leaf conductance to water vapour (gL), transpiration rate (EL), relative water content (RWC) and water potential (L) were measured between pre-dawn and sunset, monthly from May to November. Parallel measurements of loss of hydraulic conductance of twigs of the current year (PLC) were made together with an estimate of whole-plant hydraulic conductance (KPLANT) on the basis of the ratio of maximum EL to (PD − MIN), where PD is pre-dawn L and MIN is the minimum diurnal L. C. siliqua saplings maintained high gL throughout the study period with high RWC (over 90%) and L. They grew rapidly and increased their foliage area (AL) by over 60% from May to winter rest. This was accompanied by low twig PLC (about 20% in September) resulting in high KPLANT all through the study period. In contrast, O. oleaster saplings underwent distinct dehydration in July, i.e. they showed stomatal closure due to a drop in RWC (to 75%) and L (to the turgor-loss point). This was apparently due to twig cavitation, resulting in a strong decrease of KPLANT. Plants, however, tolerated summer drought, and showed growth (AL increased by 15% from May to November). Saplings of Q. suber and Q. pubescens were much more vulnerable to twig cavitation (PLC was 35–48% from June to November) than the other two species, and their average KPLANT was lower. Saplings of Q. suber and Q. pubescens grew only during the wet spring period, and no new foliage was produced thereafter. Changes in twig hydraulic conductance played a dominant role in determining changes in KPLANT in that the two variables were well correlated to each other (r = 0.68 for P = 0.001). We conclude that C. siliqua is an ideal candidate for reforestation of Sicilian degraded areas as is O. oleaster that, however, requires some additional water supply in the summer, at least during the early years after plantation. In wetter locations of Sicily, to an altitude between 0 and 500 m, Q. suber and Q. pubescens can be used for reforestation with expected higher competitiveness of the latter over the former species.
Keywords: cavitation; Drought resistance; hydraulics; Mediterranean trees; Reforestation; water relations

Efeito da Idade e da Fertilização na Qualidade das Plantas do Sobreiro (Quercus - Merouani, Hachemi; Costa, Filipe; Sampaio, Teresa; Lourenço, Maria João; Pereira, João Santos; Almeida, Maria Helena (Congresso Florestal Nacional, 5º, Viseu, 2005, 2003)
A plantação tem sido uma técnica muito utilizada em projectos de reflorestação do montado de sobro, uma vez que a sementeira é limitada temporalmente pelo facto de não se dominar a conservação a longo prazo das glandes (sementes recalcitrantes). Consequentemente, a produção das plantas provém exclusivamente de sementes frescas (Novembro - Janeiro) condicionando a sua idade no momento da plantação (10-14 meses). A idade da planta influencia o seu potencial de crescimento após a plantação, estando regulamentada por legislação (DecretoLei nº 205/2000, de 12 de Setembro). A aplicação de fertilizantes tem sido sugerida como uma técnica de produção em viveiro destinada a melhorar a qualidade da planta. No âmbito de diversos projectos (CREOAK-QLK5-CT-2002-01594; POCTI/41359/AGG/2001), temos vindo a aprofundar o conhecimento sobre a qualidade das plantas do sobreiro. Produziram-se em viveiro, plantas de idade diferente provenientes de sementes frescas e conservadas (3 e 6 meses), obtendo-se respectivamente plantas de 9, 7 e 5 meses. Nas plantas de 7 meses, foi aplicado um tratamento de fertilização (50 ml da solução NPK, 12-2-12) e de micorrização (Pisolithus tinctorius). Foram avaliados diferentes parâmetros morfológicos e fisiológicos durante a fase de crescimento da planta em viveiro, assim como o potencial de crescimento das raízes no momento de plantação. Os resultados apresentados centram-se no efeito de ambos os factores (idade à plantação e fertilização) na qualidade das plantas.
Keywords: Conservação de glandes; idade da planta; Material Florestal de Reprodução; Q. suber; Qualidade

Efeito da Idade e da Fertilização na Qualidade das Plantas do Sobreiro (Quercus - Merouani, Hachemi; Costa, Filipe; Sampaio, Teresa; Lourenço, Maria João; Pereira, João Santos; Almeida, Maria Helena (Congresso Florestal Nacional, 5º, Viseu, 2005, 2003)
A plantação tem sido uma técnica muito utilizada em projectos de reflorestação do montado de sobro, uma vez que a sementeira é limitada temporalmente pelo facto de não se dominar a conservação a longo prazo das glandes (sementes recalcitrantes). Consequentemente, a produção das plantas provém exclusivamente de sementes frescas (Novembro - Janeiro) condicionando a sua idade no momento da plantação (10-14 meses). A idade da planta influencia o seu potencial de crescimento após a plantação, estando regulamentada por legislação (DecretoLei nº 205/2000, de 12 de Setembro). A aplicação de fertilizantes tem sido sugerida como uma técnica de produção em viveiro destinada a melhorar a qualidade da planta. No âmbito de diversos projectos (CREOAK-QLK5-CT-2002-01594; POCTI/41359/AGG/2001), temos vindo a aprofundar o conhecimento sobre a qualidade das plantas do sobreiro. Produziram-se em viveiro, plantas de idade diferente provenientes de sementes frescas e conservadas (3 e 6 meses), obtendo-se respectivamente plantas de 9, 7 e 5 meses. Nas plantas de 7 meses, foi aplicado um tratamento de fertilização (50 ml da solução NPK, 12-2-12) e de micorrização (Pisolithus tinctorius). Foram avaliados diferentes parâmetros morfológicos e fisiológicos durante a fase de crescimento da planta em viveiro, assim como o potencial de crescimento das raízes no momento de plantação. Os resultados apresentados centram-se no efeito de ambos os factores (idade à plantação e fertilização) na qualidade das plantas.
The following values have no corresponding Zotero field: periodical: Congresso Florestal Nacional, 5º, Viseu, 2005
Keywords: Conservação de glandes; idade da planta; Material Florestal de Reprodução; Q. suber; Qualidade

Effect of nursery location and outplanting date on field performance of Pinus halepensis and Quercus ilex seedlings - Pardos, M.; Royo, A.; Gil, L.; Pardos, J. A. (Forestry, 2003)
One-year-old seedlings of Aleppo pine (Pinus halepensis Mill.) and holm oak (Quercus ilex L.) were over-wintered in the nursery under two contrasting conditions (greenhouse vs outdoors), which were chosen to simulate coastal vs inland thermal regimes. Seedling morphology, root growth potential (RGP) and shoot cold hardiness were assessed at lifting (at monthly intervals from November to March), and related to survival and field performance during two growing seasons. At lifting, behaviour outdoors was similar in both species. Conversely, the milder conditions in the greenhouse affected nursery performance in Aleppo pine seedlings (shoot growth during winter, low cold hardiness, low RGP), and influenced field performance negatively. Thus, nursery thermal regime had a significant effect on survival of outplanted Aleppo pine seedlings, and autumn outplanting appears to be the preferred option for this species. This issue does not seem as relevant in holm oak, a species less sensitive to frost. Minimum field temperatures in the 3 weeks around outplanting date were a critical acclimation period for Aleppo pine seedlings. Higher RGP at lifting was related to higher survival in Aleppo pine and taller holm oak seedlings. There was also a significant correlation between mortality after outplanting and foliar electrolyte leakage in Aleppo pine. Thus, cold hardiness is a good physiological indicator for determining the best lifting and planting dates in Aleppo pine, and RGP shows more promise for assessing holm oak vitality.
10.1093/forestry/76.1.6710.1093/forestry/76.1.67
Keywords: nursery location; outplanting; Pinus halepensis; Quercus ilex; Root growth; seedlings; shoot growth; survival (voyant)

Effect of nursery location and outplanting date on field performance of Pinus halepensis and Quercus ilex seedlings - Pardos, M; Royo, A; Gil, L; Pardos, J A (Forestry, 2003)
One-year-old seedlings of Aleppo pine (Pinus halepensis Mill.) and holm oak (Quercus ilex L.) were over-wintered in the nursery under two contrasting conditions (greenhouse vs outdoors), which were chosen to simulate coastal vs inland thermal regimes. Seedling morphology, root growth potential (RGP) and shoot cold hardiness were assessed at lifting (at monthly intervals from November to March), and related to survival and field performance during two growing seasons. At lifting, behaviour outdoors was similar in both species. Conversely, the milder conditions in the greenhouse affected nursery performance in Aleppo pine seedlings (shoot growth during winter, low cold hardiness, low RGP), and influenced field performance negatively. Thus, nursery thermal regime had a significant effect on survival of outplanted Aleppo pine seedlings, and autumn outplanting appears to be the preferred option for this species. This issue does not seem as relevant in holm oak, a species less sensitive to frost. Minimum field temperatures in the 3 weeks around outplanting date were a critical acclimation period for Aleppo pine seedlings. Higher RGP at lifting was related to higher survival in Aleppo pine and taller holm oak seedlings. There was also a significant correlation between mortality after outplanting and foliar electrolyte leakage in Aleppo pine. Thus, cold hardiness is a good physiological indicator for determining the best lifting and planting dates in Aleppo pine, and RGP shows more promise for assessing holm oak vitality.
10.1093/forestry/76.1.67
Keywords: nursery location; outplanting; Pinus halepensis; Quercus ilex; Root growth; seedlings; shoot growth; survival (voyant)

Effect of Tannins from Quercus suber and Quercus coccifera Leaves on Ethanol-Induced Gastric Lesions in Mice - Khennouf, Seddik; Benabdallah, Hassiba; Gharzouli, Kamel; Amira, Smain; Ito, Hideyuki; Kim, Tae-Hoon; Yoshida, Takashi; Gharzouli, Akila (Journal of Agricultural and Food Chemistry, 2003)
The gastroprotective effects of 70% acetone extracts of Quercus suber and Quercus coccifera leaves and of tannins (pedunculagin, castalagin, phillyraeoidin A, and acutissimin B) purified from these extracts were examined in the mouse using the ethanol-induced gastric ulcer model. Both extracts (25, 50, and 100 mg/kg), given orally, prevented the formation of ethanol-induced lesions in the stomach. The percent protection varied between 68 and 91%. Purified tannins (50 mg/kg) were also effective in protecting the stomach against ethanol, and the percent protection varied from 66 to 83%. Castalagin was the most potent. Both extracts and all of the tannins tested (10, 25, and 50 ?g/mL) strongly inhibited (55?65%) the lipid peroxidation of rabbit brain homogenate. These results suggest that the gastroprotective effects of extracts of Q. suber and Q. coccifera leaves and the purified tannins in this experimental model are related to their anti-lipoperoxidant properties. Keywords: Experimental gastric ulcer; lipid peroxidation; medicinal plants; Quercus sp.; tannins; castalagin
From Duplicate 2 (Effect of Tannins from Quercus suber and Quercus coccifera Leaves on Ethanol-Induced Gastric Lesions in Mice - Khennouf, Seddik; Benabdallah, Hassiba; Gharzouli, Kamel; Amira, Smain; Ito, Hideyuki; Kim, Tae-Hoon; Yoshida, Takashi; Gharzouli, Akila)
Keywords: Acetone; Animals; Biphenyl Compounds; castalagin; Catechols; Catechols: therapeutic use; Ethanol; Experimental gastric ulcer; Hydrolyzable Tannins; lipid peroxidation; Lipid Peroxidation: drug effects; Male; Medicinal plants; Mice; Plant Extracts; Plant Extracts: chemistry; Plant Extracts: therapeutic use; Plant Leaves; Plant Leaves: chemistry; Quercus; Quercus sp.; Quercus: chemistry; Rabbits; Stomach Ulcer; Stomach Ulcer: chemically induced; Stomach Ulcer: prevention & control; Tannins; Tannins: pharmacology; Tannins: therapeutic use

Effects of tension wood on specific conductivity and vulnerability to embolism of Quercus ilex seedlings grown at two atmospheric CO2 concentrations - Gartner, Barbara L; Roy, Jacques; Huc, Roland (Tree Physiology, 2003)
To determine whether there are decreases in hydraulic function of a woody stem when it has increased mechanical loading, Quercus ilex L. seedlings were grown upright or inclined to force the production of large amounts of tension wood (TW). Seedlings were grown in ambient or elevated carbon dioxide concentrations ([CO2]) for 16–17 months to provide two sets of seedlings differing in growth rates and allocation patterns. In both CO2 environments, inclination caused formation of large amounts of TW at the base and mid-section of most stems, but not at the stem tips. Contrary to expectation, there were no significant effects of stem inclination or amount of TW on specific conductivity (ks) or vulnerability to embolism. Samples with high amounts of TW had higher vessel frequency, similar average vessel lumen area, similar vessel lumen fraction (6% of the transverse area), elevated frequency of vessels in the smallest diameter class, and higher wood density than samples with very little TW. Samples from seedlings in the elevated [CO2] treatment had similar vessel frequency, larger average vessel lumen area (caused by a higher frequency of large-diameter vessels), similar vessel lumen fraction, and similar wood density as samples from seedlings in the ambient [CO2] treatment. There was a strong position effect: the highest wood density and lowest ks were at the stem base, intermediate values were at the middle, and the lowest density and highest ks were at the stem tip. We conclude that, in a species that uses different cells for mechanical support and water transport, there can be large modifications in performance of the mechanical function through TW formation without impacting the water transport functions—ks and vulnerability to embolism.
10.1093/treephys/23.6.387
Keywords: ecological wood anatomy; evergreen; hydraulic architecture; Mediterranean; structure/function relationship

Effects of tension wood on specific conductivity and vulnerability to embolism of Quercus ilex seedlings grown at two atmospheric CO2 concentrations - Gartner, Barbara L.; Roy, Jacques; Huc, Roland (Tree Physiology, 2003)
To determine whether there are decreases in hydraulic function of a woody stem when it has increased mechanical loading, Quercus ilex L. seedlings were grown upright or inclined to force the production of large amounts of tension wood (TW). Seedlings were grown in ambient or elevated carbon dioxide concentrations ([CO2]) for 16–17 months to provide two sets of seedlings differing in growth rates and allocation patterns. In both CO2 environments, inclination caused formation of large amounts of TW at the base and mid-section of most stems, but not at the stem tips. Contrary to expectation, there were no significant effects of stem inclination or amount of TW on specific conductivity (ks) or vulnerability to embolism. Samples with high amounts of TW had higher vessel frequency, similar average vessel lumen area, similar vessel lumen fraction (6% of the transverse area), elevated frequency of vessels in the smallest diameter class, and higher wood density than samples with very little TW. Samples from seedlings in the elevated [CO2] treatment had similar vessel frequency, larger average vessel lumen area (caused by a higher frequency of large-diameter vessels), similar vessel lumen fraction, and similar wood density as samples from seedlings in the ambient [CO2] treatment. There was a strong position effect: the highest wood density and lowest ks were at the stem base, intermediate values were at the middle, and the lowest density and highest ks were at the stem tip. We conclude that, in a species that uses different cells for mechanical support and water transport, there can be large modifications in performance of the mechanical function through TW formation without impacting the water transport functions—ks and vulnerability to embolism.
10.1093/treephys/23.6.38710.1093/treephys/23.6.387
Keywords: ecological wood anatomy; evergreen; hydraulic architecture; Mediterranean; structure/function relationship

Effects of the Argentine ant Linepithema humile on seed dispersal and seedling emergence of Rhamnus alaternus - Gómez, C; Pons, P; Bas, J M (ECOGRAPHY, 2003)
We studied influence of the Argentine ant's Linepithema humile occurrence on seed dispersal of Rhamnus alaternus (Rhamnaceae). Rhamnus alaternus is a fleshy fruit plant dispersed primarily by birds; the seeds have an elaiosome attractive to ants. The observations were made in two study plots of Mediterranean cork-oak forests (one invaded and the other not invaded by L. humile) over two years. For R. alaternus, presence of L. humile was associated with of the following: reduction of seed transport to ant nests (80.2% of seed offered were removed in non-invaded vs 7.1% in invaded area), a shorter seed dispersal distance (mean = 90.2 cm, in non-invaded vs 1.1 cm in invaded area), increase in seed retention time on the soil surface (median time in non-invaded was 50 vs 209.2 min in invaded area) and increased vulnerability to predation. In addition there was lower probability of seedling emergence, due to little elaiosome removal from the seeds (82.0% of emergence for seeds without elaiosome and 57.3% for seeds with elaiosome). These results, similar to findings obtained in South African fynbos, confirm that the Argentine ant invasion can strongly affect ecosystem processes in the Mediterranean biome.

The epiphytic bryoflora of the Jbel Bouhalla (Rif, Morocco), including a new variety of moss, Orthotrichum speciosum var. brevisetum. - Draper, I; Lara, F; Albertos, B; Garilleti, R; Mazimpaka, V (Journal of Bryology, 2003)
The epiphytic bryoflora of Jbel Bouhalla, a mountain sited in the Rif range (northern Morocco), is catalogued, resulting in a list of 48 taxa (45 mosses and 3 liverworts). One new variety, Orthotrichum speciosum var. brevisetum, is described, and some new records are reported: Orthotrichum shawii and O. pallens are new to northern Africa, while Habrodon perpusillus and O. speciosum var. speciosum are new to Morocco. [ABSTRACT FROM AUTHOR]
Keywords: Bryophyte flora; chorology; epiphytes; Morocco; northern Africa; Orthotrichum speciosum var. brevisetum; Rif

The epiphytic bryoflora of the Jbel Bouhalla (Rif, Morocco), including a new variety of moss, Orthotrichum speciosum var. brevisetum. - Draper, I.; Lara, F.; Albertos, B.; Garilleti, R.; Mazimpaka, V. (Journal of Bryology, 2003)
The epiphytic bryoflora of Jbel Bouhalla, a mountain sited in the Rif range (northern Morocco), is catalogued, resulting in a list of 48 taxa (45 mosses and 3 liverworts). One new variety, Orthotrichum speciosum var. brevisetum, is described, and some new records are reported: Orthotrichum shawii and O. pallens are new to northern Africa, while Habrodon perpusillus and O. speciosum var. speciosum are new to Morocco. [ABSTRACT FROM AUTHOR]
Keywords: Bryophyte flora; chorology; epiphytes; Morocco; northern Africa; Orthotrichum speciosum var. brevisetum; Rif

Ergovaline occurrence in grasses infected by fungal endophytes of semi-arid pastures in Spain - Vazquez de Aldana, Beatriz R; Zabalgogeazcoa, Iigo; Garcia Ciudad, Antonia; Garcia Criado, Balbino (Journal of the Science of Food and Agriculture, 2003)
: Ergovaline is a mycotoxin produced by fungal endophytes belonging to Neotyphodium and Epichloe¨ spp in several host grass species. Owing to the production of this alkaloid, the ingestion of endophyte-infected grasses causes toxicosis in grazing animals. The aim of this work was to determine if ergovaline is produced in several grasses (Agrostis castellana Boiss and Reuter, Brachypodium phoenicoides (L) Roemer and Schultes, Dactylis glomerata L, Festuca arundinacea Schreb, Festuca arundinacea Schreb subsp fenas (Lag) Arcangeli, Festuca ovina L, Festuca rubra L, Holcus lanatus L and Lolium perenne L) infected by fungal endophytes in ‘dehesa’ pastures in Spain. Forage and seed samples of several ecotypes of these grass species were analysed for their ergovaline content by HPLC with ﬂuorescence detection. The ergovaline content ranged between 0.03 and 0.85mg g 1 in forage and 0.28 and 3.17mg g 1 in seed samples of F arundinacea, between 0.00 and 0.08mg g 1 in forage and 0.02 and 0.19mg g 1 in seed samples of F rubra, between 0.00 and 0.02mg g 1 in forage samples of H lanatus, and was 0.11mg g 1 in one ecotype of F ovina. All nine ecotypes of F rubra had ergovaline in seed samples, but in three ecotypes the alkaloid was not detected in forage samples. No ergovaline was detected in the other four endophyte-infected grasses analysed. The ergovaline content should be considered as an anti-quality parameter to be measured when the nutritional quality of these pastures is evaluated
Keywords: dehesa grasslands; endophytes; epichloe; ergovaline; mycotoxins; neotyphodium

Ergovaline occurrence in grasses infected by fungal endophytes of semi-arid pastures in Spain - Vazquez de Aldana, Beatriz R.; Zabalgogeazcoa, Iigo; Garcia Ciudad, Antonia; Garcia Criado, Balbino (Journal of the Science of Food and Agriculture, 2003)
: Ergovaline is a mycotoxin produced by fungal endophytes belonging to Neotyphodium and Epichloe¨ spp in several host grass species. Owing to the production of this alkaloid, the ingestion of endophyte-infected grasses causes toxicosis in grazing animals. The aim of this work was to determine if ergovaline is produced in several grasses (Agrostis castellana Boiss and Reuter, Brachypodium phoenicoides (L) Roemer and Schultes, Dactylis glomerata L, Festuca arundinacea Schreb, Festuca arundinacea Schreb subsp fenas (Lag) Arcangeli, Festuca ovina L, Festuca rubra L, Holcus lanatus L and Lolium perenne L) infected by fungal endophytes in ‘dehesa’ pastures in Spain. Forage and seed samples of several ecotypes of these grass species were analysed for their ergovaline content by HPLC with ﬂuorescence detection. The ergovaline content ranged between 0.03 and 0.85mg g 1 in forage and 0.28 and 3.17mg g 1 in seed samples of F arundinacea, between 0.00 and 0.08mg g 1 in forage and 0.02 and 0.19mg g 1 in seed samples of F rubra, between 0.00 and 0.02mg g 1 in forage samples of H lanatus, and was 0.11mg g 1 in one ecotype of F ovina. All nine ecotypes of F rubra had ergovaline in seed samples, but in three ecotypes the alkaloid was not detected in forage samples. No ergovaline was detected in the other four endophyte-infected grasses analysed. The ergovaline content should be considered as an anti-quality parameter to be measured when the nutritional quality of these pastures is evaluated
Keywords: dehesa grasslands; endophytes; epichloe; ergovaline; mycotoxins; neotyphodium

An examination of the interaction between climate, soil and leaf area index in a Quercus ilex ecosystem - Hoff, Corine; Rambal, Serge (Ann. For. Sci., 2003)
In Mediterranean-type ecosystems, water availability is one of the most significant variables that regulates whole plant leaf area. An equilibrium should exist between climate, soil and leaf area in such water-limited conditions. The aim of this study was to identify the relations between leaf area index (LAI), environment (climate, soil) and fluxes (water, carbon) in Mediterranean evergreen oak (Quercus ilex L.) ecosystems. To achieve this objective, 50-years simulations were performed using the FOREST-BGC model by varying LAI for a reference site and for different climates and soil water holding capacities (SWC). Transpiration, drought stress, net photosynthesis and canopy water use efficiency (WUE) were examined on a yearly basis for the last ten years of the simulation. Similar to other findings, our results show that LAI depends on site water availability, including both climate (precipitation, potential evapotranspiration) and soil factors (e.g. water storage capacity). Low SWC limit the development of the ecosystem. On high SWC soils, development is mainly limited by the climate. When LAI increases under constant SWC and climate conditions, the decrease in annual transpiration per unit of LAI is accompanied by an increase in drought stress. Equilibrium LAI maximizes carbon assimilation. For the reference site, the equilibrium LAI is close to the observed value, 3.25. The corresponding transpiration, assimilation and WUE are 375 mm, 1251 g C m -2 and 3.1 mmol CO 2 mol -1 H 2O, respectively. For the different sites, there is an hyperbolic decline of WUE with increasing SWC. This implies that production efficiency per unit leaf area is higher in most water-limited environments. Our study shows that a model such as FOREST-BGC allows inter-relations between water balance, carbon balance and drought stress to be taken into account to better understand ecosystem LAI.
Keywords: climate; evergreen oak; hydrological equilibrium; leaf area index; mediterranean-type ecosystem; Quercus ilex L.; soil factor; Water availability

Fatty acid composition of abdominal adipose tissue in broilers fed green-oak (Quercus ilex), cork oak acorn (Quercus Suber L.) based diets - Bouderoua, Kaddour; Selselet-Attou, Ghalem (Anim. Res., 2003)
Male broilers, 30 for every diet, were fed for six weeks, diets containing 60% green oak (GO) and oak cork (CO) acorns compared to 60% corn (C). The body weight of the chickens fed the oak acorn-based diets was 25% lower than that of the controls (C). Abdominal adipose tissue (AAT) was twice heavier in the controls compared to broilers fed oak acorn-based diets. The total lipids of AAT were higher in the controls compared to the oak acorn fed chickens (34.4 against 15.3 g per 100 g of AAT in the CO). The palmitic and oleic acid proportions were comparable in the AAT of chickens fed with the different diets. The proportion of linoleic acid, obtained exclusively by the diets, was significantly higher in the chickens fed oak acorn-based diets (23%), compared to the controls (19%). Reciprocally, palmitoleic acid was present in a small proportion in chickens fed oak acorns (4 to 5%). The observed variation of the fatty acid content of abdominal fat of acorn-fed chickens requires further research on the precise nutrient digestibility of oak acorns before considering them as a potential feed.
Keywords: Adipose Tissue; broilers; Lipids; lipogenesis; oak acorn

Fatty acid composition of abdominal adipose tissue in broilers fed green-oak (Quercus ilex), cork oak acorn (Quercus Suber L.) based diets - Bouderoua, Kaddour; Selselet-Attou, Ghalem (Anim. Res., 2003)
Male broilers, 30 for every diet, were fed for six weeks, diets containing 60% green oak (GO) and oak cork (CO) acorns compared to 60% corn (C). The body weight of the chickens fed the oak acorn-based diets was 25% lower than that of the controls (C). Abdominal adipose tissue (AAT) was twice heavier in the controls compared to broilers fed oak acorn-based diets. The total lipids of AAT were higher in the controls compared to the oak acorn fed chickens (34.4 against 15.3 g per 100 g of AAT in the CO). The palmitic and oleic acid proportions were comparable in the AAT of chickens fed with the different diets. The proportion of linoleic acid, obtained exclusively by the diets, was significantly higher in the chickens fed oak acorn-based diets (23%), compared to the controls (19%). Reciprocally, palmitoleic acid was present in a small proportion in chickens fed oak acorns (4 to 5%). The observed variation of the fatty acid content of abdominal fat of acorn-fed chickens requires further research on the precise nutrient digestibility of oak acorns before considering them as a potential feed.
Keywords: Adipose Tissue; broilers; Lipids; lipogenesis; oak acorn

Fruit abortion, developmental selection and developmental stability in Quercus ilex. - Díaz, Mario; Møller, Anders P; Pulido, Fernando J (Oecologia, 2003)
Fruit abortion has been hypothesized to be a parental means of selective removal of propagules with low viability. In particular, aborted zygotes have been suggested to have developmentally deviant phenotypes, and surviving offspring may therefore give rise to adults with a developmentally stable phenotype. We tested predictions from this hypothesis using acorns of holm oaks Quercus ilex as a model system. Fecundity of oak trees was negatively related to mean fluctuating asymmetry of leaves, and abortion rates were positively related to leaf fluctuating asymmetry in at least one population. Aborted acorns were asymmetric in 83-99% of cases in three samples, while mature acorns were only asymmetric in 57-78% of cases. Acorn asymmetry was unrelated to germination probability and germination date, and had no significant effect on number of leaves, leaf mass, stem mass, seedling height or leaf area of seedlings. However, acorn asymmetry affected the trade-off between number and size of leaves in seedlings. Seedlings from asymmetric acorns showed a positive relationship between acorn size and number of leaves, but no relationships between acorn size and leaf area, while symmetric acorns showed the opposite. A positive relationship between acorn size and number of leaves in spring was found for naturally emerged seedlings that died during their first summer, whereas the number of leaves produced by surviving seedlings did not depend on acorn size. These findings are consistent with the hypothesis that stressed trees selectively abort propagules of low viability, and that developmental selection acts on a measure of developmental instability of fruits.
Keywords: acorn; Fluctuating asymmetry; Leaf number; Leaf size; Maternal effect

Fruit abortion, developmental selection and developmental stability in Quercus ilex. - Díaz, Mario; Møller, Anders P.; Pulido, Fernando J. (Oecologia, 2003)
Fruit abortion has been hypothesized to be a parental means of selective removal of propagules with low viability. In particular, aborted zygotes have been suggested to have developmentally deviant phenotypes, and surviving offspring may therefore give rise to adults with a developmentally stable phenotype. We tested predictions from this hypothesis using acorns of holm oaks Quercus ilex as a model system. Fecundity of oak trees was negatively related to mean fluctuating asymmetry of leaves, and abortion rates were positively related to leaf fluctuating asymmetry in at least one population. Aborted acorns were asymmetric in 83-99% of cases in three samples, while mature acorns were only asymmetric in 57-78% of cases. Acorn asymmetry was unrelated to germination probability and germination date, and had no significant effect on number of leaves, leaf mass, stem mass, seedling height or leaf area of seedlings. However, acorn asymmetry affected the trade-off between number and size of leaves in seedlings. Seedlings from asymmetric acorns showed a positive relationship between acorn size and number of leaves, but no relationships between acorn size and leaf area, while symmetric acorns showed the opposite. A positive relationship between acorn size and number of leaves in spring was found for naturally emerged seedlings that died during their first summer, whereas the number of leaves produced by surviving seedlings did not depend on acorn size. These findings are consistent with the hypothesis that stressed trees selectively abort propagules of low viability, and that developmental selection acts on a measure of developmental instability of fruits.
The following values have no corresponding Zotero field: accession-num: 12721827
Keywords: acorn; Fluctuating asymmetry; Leaf number; Leaf size; Maternal effect

A global change-induced biome shift in the Montseny mountains (NE Spain) - Penuelas, Josep; Boada, Martí (Global Change Biology, 2003)
Shifts in plant species and biome distribution in response to warming have been described in past climate changes. However, reported evidence of such shifts under current climate change is still scarce. By comparing current and 1945 vegetation distribution in the Montseny mountains (Catalonia, NE Spain), we report here a progressive replacement of cold-temperate ecosystems by Mediterranean ecosystems. Beech (Fagus sylvatica) forest has shifted altitudinally upwards by ca. 70 m at the highest altitudes (1600–1700 m). Both the beech forests and the heather (Calluna vulgaris) heathlands are being replaced by holm oak (Quercus ilex) forest at medium altitudes (800–1400 m). This beech replacement has been observed to occur through a progressive isolation and degradation of beech stands. In ‘isolated’ (small and surrounded by holm oaks) beech stands, beech trees are 30% more defoliated, beech recruitment is 41% lower, and holm oak recruitment is three times higher than in ‘continental’ (large and continuous) beech stands. The progressively warmer conditions, complemented by the land use changes (mainly the cessation of traditional land management) are the apparent causes, providing a paradigmatic example of global change affecting distributions of plant species and biomes.
The following values have no corresponding Zotero field: publisher: Blackwell Science, Ltd
Keywords: altitudinal shift; biome replacement; Calluna heathland; climate change; defoliation status; Fagus sylvatica; Land use change; mediterranean forest; Montseny mountains; Quercus ilex; Recruitment; temperate forest

Habitat effects and shooting techniques on two wild boar (Sus scrofa) populations in Spain and Portugal - Fernández-Llario, P; Mateos-Quesada, P; Silvério, A; Santos, P (Zeitschrift für Jagdwissenschaft, 2003)
In the last decades, wild boar (Sus scrofa) distribution has increased world-wide, the Iberian Peninsula being no exception. The wild boar now inhabits almost the entire Iberian territory, where today it is one of the most important big game species. In this paper, for the first time, bag analysis from two ecological different regions are presented and compared to the employed hunting techniques. One represents the well-preserved Mediterranean forests of south-western Spain, the other, located in the south of Portugal, is a farmland with interspersed forest areas. Our results indicate a stronger hunting intensity and also a higher wild boar population density in the Portuguese study areas. The stronger hunting intensity may result in a younger wild boar population. We also found considerable differences between the shooting techniques used in both regions and those employed in the north-east of the peninsula. It does therefore not seem advisable to directly compare bag statistics from different regions of the Iberian peninsula.
Keywords: habitats; Mediterranean; Populations; Portugal; shooting techniques; Spain; Sus scrofa; Wild boar

Habitat effects and shooting techniques on two wild boar (Sus scrofa) populations in Spain and Portugal - Fernandez-Llario, P.; Mateos-Quesada, P.; Silvério, A.; Santos, P. (Zeitschrift für Jagdwissenschaft, 2003)
In the last decades, wild boar (Sus scrofa) distribution has increased world-wide, the Iberian Peninsula being no exception. The wild boar now inhabits almost the entire Iberian territory, where today it is one of the most important big game species. In this paper, for the first time, bag analysis from two ecological different regions are presented and compared to the employed hunting techniques. One represents the well-preserved Mediterranean forests of south-western Spain, the other, located in the south of Portugal, is a farmland with interspersed forest areas. Our results indicate a stronger hunting intensity and also a higher wild boar population density in the Portuguese study areas. The stronger hunting intensity may result in a younger wild boar population. We also found considerable differences between the shooting techniques used in both regions and those employed in the north-east of the peninsula. It does therefore not seem advisable to directly compare bag statistics from different regions of the Iberian peninsula.
Keywords: habitats; Mediterranean; Populations; Portugal; shooting techniques; Spain; Sus scrofa; Wild boar

Hydrological properties of cork container media - Carmona, E.; Ordovas, J.; Moreno, M. T.; Aviles, M.; Aguado, M. T.; Ortega, M. C. (HORTSCIENCE, 2003)
Static hydrological properties \{[\}aeration capacity; easily available water, reserve water, water release curves: theta(v)(Psi(m)), and specific humidity curves] and dynamic hydrological properties (saturated and unsaturated hydraulic conductivity) of substrates based on industrial cork residue (the bark of Quercus suber L.) and cork compost were studied. Samples of similar granulometry have been used to establish the effect of cork composting on the aforementioned physical properties. Different models were tested to describe the mechanism of water release from these materials. Van Genuchten's model (Van Genuchten, 1978) was the best fit and produced specific humidity curves that revealed slight differences in the ratio of water capacity function. When cork residues were composted for 7 months, important changes occurred in hydrological properties of the material as it became more wettable. Water retention significantly increased from 45% to 54%, at a potential of 5 kPa, although this did not necessarily result in increased water available to plants. A study of the unsaturated hydraulic conductivity (K-unsat) of these materials revealed a significant decrease in the K-unsat water potential at 0-5 kPa, which corresponds to the range in which the irrigation with these substrates was usually carried out. The long composting process resulted in increased K-unsat between 4 and 5 times that of uncomposted material, which would improve the water supply to the plant.
The following values have no corresponding Zotero field: pub-location: 113 S WEST ST, STE 200, ALEXANDRIA, VA 22314-2851 USA publisher: AMER SOC HORTICULTURAL SCIENCE
Keywords: growing media; horticultural substrate; hydraulic conductivity; physical properties; water release curves

Hydrological properties of cork container media - Carmona, E; Ordovas, J; Moreno, M T; Aviles, M; Aguado, M T; Ortega, M C (HORTSCIENCE, 2003)
Static hydrological properties \{[\}aeration capacity; easily available water, reserve water, water release curves: theta(v)(Psi(m)), and specific humidity curves] and dynamic hydrological properties (saturated and unsaturated hydraulic conductivity) of substrates based on industrial cork residue (the bark of Quercus suber L.) and cork compost were studied. Samples of similar granulometry have been used to establish the effect of cork composting on the aforementioned physical properties. Different models were tested to describe the mechanism of water release from these materials. Van Genuchten's model (Van Genuchten, 1978) was the best fit and produced specific humidity curves that revealed slight differences in the ratio of water capacity function. When cork residues were composted for 7 months, important changes occurred in hydrological properties of the material as it became more wettable. Water retention significantly increased from 45% to 54%, at a potential of 5 kPa, although this did not necessarily result in increased water available to plants. A study of the unsaturated hydraulic conductivity (K-unsat) of these materials revealed a significant decrease in the K-unsat water potential at 0-5 kPa, which corresponds to the range in which the irrigation with these substrates was usually carried out. The long composting process resulted in increased K-unsat between 4 and 5 times that of uncomposted material, which would improve the water supply to the plant.
Keywords: growing media; horticultural substrate; hydraulic conductivity; physical properties; water release curves

Identification, measurement and interpretation of tree rings in woody species from mediterranean climates. - Cherubini, Paolo; Gartner, Barbara L; Tognetti, Roberto; Bräker, Otto U; Schoch, Werner; Innes, John L (Biological reviews of the Cambridge Philosophical Society, 2003)
We review the literature dealing with mediterranean climate, vegetation, phenology and ecophysiology relevant to the understanding of tree-ring formation in mediterranean regions. Tree rings have been used extensively in temperate regions to reconstruct responses of forests to past environmental changes. In mediterranean regions, studies of tree rings are scarce, despite their potential for understanding and predicting the effects of global change on important ecological processes such as desertification. In mediterranean regions, due to the great spatio-temporal variability of mediterranean environmental conditions, tree rings are sometimes not formed. Often, clear seasonality is lacking, and vegetation activity is not always associated with regular dormancy periods. We present examples of tree-ring morphology of five species (Arbutus unedo, Fraxinus ornus, Quercus cerris, Q. ilex, Q. pubescens) sampled in Tuscany, Italy, focusing on the difficulties we encountered during the dating. We present an interpretation of anomalies found in the wood structure and, more generally, of cambial activity in such environments. Furthermore, we propose a classification of tree-ring formation in mediterranean environments. Mediterranean tree rings can be dated and used for dendrochronological purposes, but great care should be taken in selecting sampling sites, species and sample trees.
Keywords: Arbutus unedo; Dendrochronology; Dendroecology; ecophysiology; Fraxinus ornus; Mediterranean climate; mediterranean tree rings; Mediterranean vegetation; Phenology; Quercus cerris; Quercus ilex; Quercus pubescens; wood anatomy

Identification, measurement and interpretation of tree rings in woody species from mediterranean climates. - Cherubini, Paolo; Gartner, Barbara L.; Tognetti, Roberto; Bräker, Otto U.; Schoch, Werner; INNES, JOHN L. (Biological reviews of the Cambridge Philosophical Society, 2003)
We review the literature dealing with mediterranean climate, vegetation, phenology and ecophysiology relevant to the understanding of tree-ring formation in mediterranean regions. Tree rings have been used extensively in temperate regions to reconstruct responses of forests to past environmental changes. In mediterranean regions, studies of tree rings are scarce, despite their potential for understanding and predicting the effects of global change on important ecological processes such as desertification. In mediterranean regions, due to the great spatio-temporal variability of mediterranean environmental conditions, tree rings are sometimes not formed. Often, clear seasonality is lacking, and vegetation activity is not always associated with regular dormancy periods. We present examples of tree-ring morphology of five species (Arbutus unedo, Fraxinus ornus, Quercus cerris, Q. ilex, Q. pubescens) sampled in Tuscany, Italy, focusing on the difficulties we encountered during the dating. We present an interpretation of anomalies found in the wood structure and, more generally, of cambial activity in such environments. Furthermore, we propose a classification of tree-ring formation in mediterranean environments. Mediterranean tree rings can be dated and used for dendrochronological purposes, but great care should be taken in selecting sampling sites, species and sample trees.
The following values have no corresponding Zotero field: accession-num: 12620063
Keywords: Arbutus unedo; Dendrochronology; Dendroecology; ecophysiology; Fraxinus ornus; Mediterranean climate; mediterranean tree rings; Mediterranean vegetation; Phenology; Quercus cerris; Quercus ilex; Quercus pubescens; wood anatomy

Imaging the mechanical properties of wood cell wall layers by atomic force modulation microscopy - Clair, B.; Arinero, R.; Leveque, G.; Ramonda, M.; Thibaut, B. (IAWA JOURNAL, 2003)
Atomic Force Microscopy in force modulation mode was used to study the elastic properties of the different fibre wall layers of the tension wood of holm oak and normal wood of boco. The method is based on the measurement of the resonance frequency of the microscope lever in contact with the sample. This frequency is related to the reduced Young modulus E{*} = E/(1-nu(2)) of the material, supposed to be isotropic. `Elastic' images of the cell are obtained simultaneously with the topographic images, which allows the observation of the mechanical properties of the cells at a nanometric scale. Layers G, S-1, S-2 and ML can clearly be distinguished. By comparison with known materials an estimation of the absolute modulus is given in the range 5-20 GPa, but should be considered with caution, because the inherent anisotropy of the materials has not been taken into account.
The following values have no corresponding Zotero field: pub-location: RIJKSHERBARIUM, PO BOX 9514, 2300 LEIDEN, NETHERLANDS publisher: INT ASSOC WOOD ANATOMISTS
Keywords: atomic force microscopy; cell wall; elastic modulus; mechanical properties; Wood

Imaging the mechanical properties of wood cell wall layers by atomic force modulation microscopy - Clair, B; Arinero, R; Leveque, G; Ramonda, M; Thibaut, B (IAWA JOURNAL, 2003)
Atomic Force Microscopy in force modulation mode was used to study the elastic properties of the different fibre wall layers of the tension wood of holm oak and normal wood of boco. The method is based on the measurement of the resonance frequency of the microscope lever in contact with the sample. This frequency is related to the reduced Young modulus E{*} = E/(1-nu(2)) of the material, supposed to be isotropic. `Elastic' images of the cell are obtained simultaneously with the topographic images, which allows the observation of the mechanical properties of the cells at a nanometric scale. Layers G, S-1, S-2 and ML can clearly be distinguished. By comparison with known materials an estimation of the absolute modulus is given in the range 5-20 GPa, but should be considered with caution, because the inherent anisotropy of the materials has not been taken into account.
Keywords: atomic force microscopy; cell wall; elastic modulus; mechanical properties; Wood

In vitro floral induction from thin longitudinal sections and micro-cuttings of juvenile cork oak material - Mulin, Manorama; Pais, M. S. S. (Trees-Structure and Function, 2003)
In vitro flowers were obtained from thin longitudinal sections excised at the proximity of the apical region or nodal regions of the main stem and axillary shoots of in vitro Quercus suber stock shoots as well as from field-grown seedlings. In vitro floral induction was also achieved from nodal segments of 8- to 9-month-old seedlings or from micro-cuttings of embryonic main shoot and its axillary shoots of 2- month-old seedlings. The more juvenile the material the shorter the period required to achieve flowering. Under the described experimental conditions we have thus been able to induce the expression of neoteny in a woody, longcycle species such as cork oak.
Keywords: apical or nodal regions; floral induction; neoteny; nodal segments or micro-cuttings; thin longitudinal sections

In vitro floral induction from thin longitudinal sections and micro-cuttings of juvenile cork oak material - Mulin, Manorama; Pais, M S S (Trees-Structure and Function, 2003)
In vitro flowers were obtained from thin longitudinal sections excised at the proximity of the apical region or nodal regions of the main stem and axillary shoots of in vitro Quercus suber stock shoots as well as from field-grown seedlings. In vitro floral induction was also achieved from nodal segments of 8- to 9-month-old seedlings or from micro-cuttings of embryonic main shoot and its axillary shoots of 2- month-old seedlings. The more juvenile the material the shorter the period required to achieve flowering. Under the described experimental conditions we have thus been able to induce the expression of neoteny in a woody, longcycle species such as cork oak.
Keywords: apical or nodal regions; floral induction; neoteny; nodal segments or micro-cuttings; thin longitudinal sections

Influence of fire severity on plant regeneration by means of remote sensing imagery - Díaz-Delgado, R.; Lloret, F.; Pons, X. (International Journal of Remote Sensing, 2003)
In this paper we analyse the interactions between fire severity (plant damage) and plant regeneration after fire by means of remote sensing imagery and a field fire severity map. A severity map was constructed over a large fire (2692 ha) occurring in July 1994 in the Barcelona province (north-east of Spain). Seven severity classes were assigned to the apparent plant damage as a function of burning intensity. Several Landsat TM and MSS images from dates immediately before and after the fire were employed to monitor plant regeneration processes as well as to evaluate the relationship with fire severity observed in situ . Plant regeneration was monitored using NDVI measurements (average class values standardized with neighbour unburned control plots). Pre-fire NDVI measurements were extracted for every plant cover category (7), field fire severity class (7), and spatial cross-tabulation of both layers (33) and compared to post-fire values. NDVI decline due to fire was positively correlated with field fire severity class. Results show different patterns of recovery for each dominant species, severity class and combination of both factors. For all cases a significant negative correlation was found between damage and regeneration ability. This work leads to a better understanding of the influence of severity, a major fire regime parameter on plant regeneration, and may aid to manage restoration on areas burned under different fire severity levels.
doi: 10.1080/01431160210144732doi: 10.1080/01431160210144732The following values have no corresponding Zotero field: publisher: Taylor & Francis
Keywords: dominant species (voyant); fire severity; NDVI; plant damage; plant regeneration

Influence of fire severity on plant regeneration by means of remote sensing imagery - Díaz-Delgado, R; Lloret, F; Pons, X (International Journal of Remote Sensing, 2003)
In this paper we analyse the interactions between fire severity (plant damage) and plant regeneration after fire by means of remote sensing imagery and a field fire severity map. A severity map was constructed over a large fire (2692 ha) occurring in July 1994 in the Barcelona province (north-east of Spain). Seven severity classes were assigned to the apparent plant damage as a function of burning intensity. Several Landsat TM and MSS images from dates immediately before and after the fire were employed to monitor plant regeneration processes as well as to evaluate the relationship with fire severity observed in situ . Plant regeneration was monitored using NDVI measurements (average class values standardized with neighbour unburned control plots). Pre-fire NDVI measurements were extracted for every plant cover category (7), field fire severity class (7), and spatial cross-tabulation of both layers (33) and compared to post-fire values. NDVI decline due to fire was positively correlated with field fire severity class. Results show different patterns of recovery for each dominant species, severity class and combination of both factors. For all cases a significant negative correlation was found between damage and regeneration ability. This work leads to a better understanding of the influence of severity, a major fire regime parameter on plant regeneration, and may aid to manage restoration on areas burned under different fire severity levels.
doi: 10.1080/01431160210144732
Keywords: dominant species (voyant); fire severity; NDVI; plant damage; plant regeneration

The key-role of topsoil moisture on CO$_2$ efflux from a Mediterranean Quercus ilex forest - Joffre, Richard; OURCIVAL, JEAN-MARC; Rambal, Serge; ROCHETEAU, ALAIN (Ann. For. Sci., 2003)
CO2 respiratory losses partly determine net carbon ecosystem exchanges. The main objective of this paper was to understand regulation imposed by soil water content and temperature on soil and ecosystem CO2 efflux in a holm oak (Quercus ilex L.) Mediterranean forest. Soil CO2 efflux was monitored monthly during 1999 and 2001. Moreover, experimental water treatments were conducted in 1999 over 9 small plots (0.3 m2) during nine months. Results showed strong decreases of soil CO2 efflux for a relative soil water content below 0.7. Ecosystem respiration measured by eddy covariance over a 4-year period showed strong sensitivity to soil water content and temperature. Severe limitations of soil and ecosystem efflux imposed by low values of soil water content occurred on about 90 days per year. The best adjustments of soil and ecosystem CO2 efflux were obtained using regression models where the exponential effect of temperature is linearly related to soil water content ( r2 = 0.68 and 0.79 for soil and ecosystem respectively). Our results highlighted strong differences in respiration sensitivity to topsoil moisture between soil and ecosystem. When the relative water content (RWC) is low (0.4), an increase of 1 °C provokes an increase of soil respiration of 5.7% and an increase of ecosystem respiration of 8.6%. For nonlimiting soil water conditions, at RWC = 1, the increases of respiration caused by a 1 °C temperature increase are of 8.5% and 16.5% for soil and ecosystem respectively. These results emphasized the probable determinant influences of changes in soil water regime for respiratory fluxes and net carbon exchanges of Mediterranean forest ecosystems.
Keywords: CO2 efflux; ecosystem respiration; Mediterranean ecosystem; Quercus ilex; Soil temperature; Soil water content

Large-scale environmental correlates of forest tree distributions in Catalonia (NE Spain) - Thuiller, Wilfried; Vayreda, Jordi; Pino, Joan; Sabaté, Santi; Lavorel, Sandra; Gracia, Carles (Global Ecology and Biogeography, 2003)
Aim To explore the environmental correlates of tree species distributions in Catalonia according to the chorological status of the species. Location The study area is the region of Catalonia, in northeastern Spain. Methods We used presence-absence data for 24 species, sampled in random plots distributed throughout forests of Catalonia. A climate model for the Catalonia region provided environmental variables. We used classiﬁcation tree analysis to explore the environmental correlates of the realized niches of tree species. The predictive accuracy of the models was assessed using the ROC curve approach. Potential distribution maps of tree species were generated for the whole Catalonia region. Results Models were ranked from low to high accuracy for the 24 species. Differences in accuracy among species were related to the chorological status of species. Zonal species, or species at the core of their range (Mediterranean and SubMediterranean species), were generally well predicted, while extrazonal species, or species at the edge of their range, were predicted only moderately well. Mediterranean species distributions showed good correlations with extreme temperatures and annual precipitation. Main conclusions The above trends conﬁrmed the difﬁculty of identifying the realized niche of species at the edges of their ranges. In contrast, Mediterranean and Sub-Mediterranean species, which were at the core of their range, were well-predicted, conﬁrming the importance of extremes of temperature and annual precipitation as effective surrogates for variables having more direct physiological roles in limiting the ability of plants to survive and grow. Maps of potential tree distributions allowed us to deﬁne suitable habitats and to highlight areas where species have been planted outside their natural distribution.
Keywords: chorology; classification tree analysis; environmental gradients; forest trees; potential distribution maps; realized niche; Spain

Large-scale environmental correlates of forest tree distributions in Catalonia (NE Spain) - Thuiller, Wilfried; Vayreda, Jordi; Pino, Joan; Sabaté, Santi; Lavorel, Sandra; Gracia, Carles (Global Ecology and Biogeography, 2003)
Aim To explore the environmental correlates of tree species distributions in Catalonia according to the chorological status of the species. Location The study area is the region of Catalonia, in northeastern Spain. Methods We used presence-absence data for 24 species, sampled in random plots distributed throughout forests of Catalonia. A climate model for the Catalonia region provided environmental variables. We used classiﬁcation tree analysis to explore the environmental correlates of the realized niches of tree species. The predictive accuracy of the models was assessed using the ROC curve approach. Potential distribution maps of tree species were generated for the whole Catalonia region. Results Models were ranked from low to high accuracy for the 24 species. Differences in accuracy among species were related to the chorological status of species. Zonal species, or species at the core of their range (Mediterranean and SubMediterranean species), were generally well predicted, while extrazonal species, or species at the edge of their range, were predicted only moderately well. Mediterranean species distributions showed good correlations with extreme temperatures and annual precipitation. Main conclusions The above trends conﬁrmed the difﬁculty of identifying the realized niche of species at the edges of their ranges. In contrast, Mediterranean and Sub-Mediterranean species, which were at the core of their range, were well-predicted, conﬁrming the importance of extremes of temperature and annual precipitation as effective surrogates for variables having more direct physiological roles in limiting the ability of plants to survive and grow. Maps of potential tree distributions allowed us to deﬁne suitable habitats and to highlight areas where species have been planted outside their natural distribution.
Keywords: chorology; classification tree analysis; environmental gradients; forest trees; potential distribution maps; realized niche; Spain

Leaf life span differs from retention time of biomass and nutrients in the crowns of evergreen species - Mediavilla, S; Escudero, a (Functional Ecology, 2003)
* 1A long leaf life span has been interpreted as an adaptation to low nutrient availability. It is commonly assumed that a long leaf life span permits a longer utilization of nutrients in the leaf biomass and that this contributes to improving nutrient use efficiency. However, a long leaf life span is also associated with other leaf traits that reduce instantaneous productivity, which might reduce the growth rate of the leaf biomass and shorten the functional life of the leaf. * 2We studied the relationships between leaf life span and the retention time of biomass and nutrient pools in several woody species with different leaf life spans. We measured the monthly variations in the total number of leaves per annual shoot, mass per leaf, and N and P contents per leaf. With these data, the leaf life span and the mean residence time (MRT) of leaf biomass and nutrient pools were estimated. * 3The increase in the total number of leaves was fast in all species studied at the start of the growth season. In contrast, in evergreen species mass per leaf and total N and P contents per leaf increased gradually after the first year of life of the leaves, and the maximum mass and nutrient contents per leaf were attained only towards the end of the lifetime of the leaves. * 4Owing to the delay in the development of mass and nutrient pools with respect to leaf number dynamics, in evergreen species leaf life span was longer than the MRT of leaf biomass and nutrient pools because part of the leaf biomass and nutrient pool remained in the crown for a shorter time than the mean duration of the individual leaves. * 5The differences between leaf life span and the MRT of the biomass and nutrients increased with leaf life span. The slow growth of evergreen leaves therefore contributes to reduce the adaptive value of a long leaf life span as a mechanism to increase the duration of the photosynthetic machinery.
Keywords: Leaf growth; leaf life span; mean residence time; nitrogen; phosphorus

Leaf life span differs from retention time of biomass and nutrients in the crowns of evergreen species - Mediavilla, S.; Escudero, A. (Functional Ecology, 2003)
* 1A long leaf life span has been interpreted as an adaptation to low nutrient availability. It is commonly assumed that a long leaf life span permits a longer utilization of nutrients in the leaf biomass and that this contributes to improving nutrient use efficiency. However, a long leaf life span is also associated with other leaf traits that reduce instantaneous productivity, which might reduce the growth rate of the leaf biomass and shorten the functional life of the leaf. * 2We studied the relationships between leaf life span and the retention time of biomass and nutrient pools in several woody species with different leaf life spans. We measured the monthly variations in the total number of leaves per annual shoot, mass per leaf, and N and P contents per leaf. With these data, the leaf life span and the mean residence time (MRT) of leaf biomass and nutrient pools were estimated. * 3The increase in the total number of leaves was fast in all species studied at the start of the growth season. In contrast, in evergreen species mass per leaf and total N and P contents per leaf increased gradually after the first year of life of the leaves, and the maximum mass and nutrient contents per leaf were attained only towards the end of the lifetime of the leaves. * 4Owing to the delay in the development of mass and nutrient pools with respect to leaf number dynamics, in evergreen species leaf life span was longer than the MRT of leaf biomass and nutrient pools because part of the leaf biomass and nutrient pool remained in the crown for a shorter time than the mean duration of the individual leaves. * 5The differences between leaf life span and the MRT of the biomass and nutrients increased with leaf life span. The slow growth of evergreen leaves therefore contributes to reduce the adaptive value of a long leaf life span as a mechanism to increase the duration of the photosynthetic machinery.
The following values have no corresponding Zotero field: publisher: Blackwell Science Ltd
Keywords: Leaf growth; leaf life span; mean residence time; nitrogen; phosphorus

Management problems in Mediterranean cork oak forests: post-fire recovery - Barberis, a; Dettori, S.; Filigheddu, M. R. (Journal of Arid Environments, 2003)
The objective of this paper is to present the results of a long-term research project carried out in north-east Sardinia, which aims to evaluate the effects of three different kinds of forest management (traditional trunk coppicing, branch pruning, and no sylvicultural practice) on the post-fire recovery of a cork oak (Quercus suber L.) stand. The most and the least effective forestry operations appeared to be traditional trunk coppicing and the branch pruning, respectively. Where traditional trunk coppicing is considered strictly necessary, the opportunity of thinning some of the new suckers should be carefully considered, as modern harvesting techniques should be combined with appropriate strategies to protect the soil from erosion.
Keywords: post-fire recovery; suckers growth

Management problems in Mediterranean cork oak forests: post-fire recovery - Barberis, a; Dettori, S; Filigheddu, M R (Journal of Arid Environments, 2003)
The objective of this paper is to present the results of a long-term research project carried out in north-east Sardinia, which aims to evaluate the effects of three different kinds of forest management (traditional trunk coppicing, branch pruning, and no sylvicultural practice) on the post-fire recovery of a cork oak (Quercus suber L.) stand. The most and the least effective forestry operations appeared to be traditional trunk coppicing and the branch pruning, respectively. Where traditional trunk coppicing is considered strictly necessary, the opportunity of thinning some of the new suckers should be carefully considered, as modern harvesting techniques should be combined with appropriate strategies to protect the soil from erosion.
Keywords: post-fire recovery; suckers growth

Maturation and germination of oak somatic embryos originated from leaf and stem explants: RAPD markers for genetic analysis of regenerants. - Sánchez, M. Concepción; Martínez, M. Teresa; Valladares, Silvia; Ferro, Enrique; Viéitez, Ana M. (Journal of plant physiology, 2003)
Experiments were performed to determine the influence of maturation medium carbohydrate content on the rates of germination and plantlet conversion (root and shoot growth) of somatic embryos from four embryogenic lines derived from leaf or internode explants of Quercus robur L. seedlings. The conversion rate was favoured by high carbohydrate content as long as the maturation medium contained at least 2% sucrose, which was necessary for healthy embryo development. Given this, sorbitol and mannitol favoured the conversion rate more efficiently than sucrose, the highest rate, 32%, being achieved by medium with 6% sorbitol and 3% sucrose. Maturation treatment did not affect the root or shoot lengths of converted embryos. In supplementary experiments, 2 weeks of gibberellic acid treatment between maturation and germination treatments did not improve germination rates, but did reduce root length and the number of leaves per regenerated plantlet. In the four embryogenic lines tested, plant recovery rate was enhanced by inclusion of benzyladenine into the germination medium following culture of the embryos on maturation medium with 6% sorbitol and 2-3% sucrose. In embryogenic systems it is important to assess the uniformity of the regenerants. Random amplified polymorphic DNA (RAPD) analysis using 32 arbitrary oligonucleotide primers was performed to study variability in DNA sequences within and between four embryogenic lines. No intraclonal nor interclonal polymorphism was detected between embryogenic lines originating from different types of explant from the same seedling, but every one of the primers detected enough polymorphism among clones originating from different plants to allow these three origins to be distinguished. No differences in DNA sequences between regenerated plantlets and their somatic embryos of origin were detected, but a nodular callus line that had lost its embryogenic capacity was found to be mutant with respect to three other clones originating from the same plantlet. This study shows that high carbohydrate levels in the maturation medium significantly increase plant conversion of oak somatic embryos, which exhibit no variation in DNA sequences when proliferated by secondary embryogenesis.
The following values have no corresponding Zotero field: accession-num: 12872492
Keywords: DNA polymorphism; genetic stability; plant conversion; Quercus robur; Somatic embryogenesis

Maturation and germination of oak somatic embryos originated from leaf and stem explants: RAPD markers for genetic analysis of regenerants. - Sánchez, M Concepción; Martínez, M Teresa; Valladares, Silvia; Ferro, Enrique; Viéitez, Ana M (Journal of plant physiology, 2003)
Experiments were performed to determine the influence of maturation medium carbohydrate content on the rates of germination and plantlet conversion (root and shoot growth) of somatic embryos from four embryogenic lines derived from leaf or internode explants of Quercus robur L. seedlings. The conversion rate was favoured by high carbohydrate content as long as the maturation medium contained at least 2% sucrose, which was necessary for healthy embryo development. Given this, sorbitol and mannitol favoured the conversion rate more efficiently than sucrose, the highest rate, 32%, being achieved by medium with 6% sorbitol and 3% sucrose. Maturation treatment did not affect the root or shoot lengths of converted embryos. In supplementary experiments, 2 weeks of gibberellic acid treatment between maturation and germination treatments did not improve germination rates, but did reduce root length and the number of leaves per regenerated plantlet. In the four embryogenic lines tested, plant recovery rate was enhanced by inclusion of benzyladenine into the germination medium following culture of the embryos on maturation medium with 6% sorbitol and 2-3% sucrose. In embryogenic systems it is important to assess the uniformity of the regenerants. Random amplified polymorphic DNA (RAPD) analysis using 32 arbitrary oligonucleotide primers was performed to study variability in DNA sequences within and between four embryogenic lines. No intraclonal nor interclonal polymorphism was detected between embryogenic lines originating from different types of explant from the same seedling, but every one of the primers detected enough polymorphism among clones originating from different plants to allow these three origins to be distinguished. No differences in DNA sequences between regenerated plantlets and their somatic embryos of origin were detected, but a nodular callus line that had lost its embryogenic capacity was found to be mutant with respect to three other clones originating from the same plantlet. This study shows that high carbohydrate levels in the maturation medium significantly increase plant conversion of oak somatic embryos, which exhibit no variation in DNA sequences when proliferated by secondary embryogenesis.
Keywords: DNA polymorphism; genetic stability; plant conversion; Quercus robur; Somatic embryogenesis

Microspore-derived embryos from Quercus suber anthers mimic zygotic embryos and maintain haploidy in long-term anther culture. - Bueno, María a; Gomez, Arancha; Sepulveda, Federico; Seguí, José M; Testillano, Pilar S; Manzanera, Jose a; Risueño, Maria-Carmen (Journal of plant physiology, 2003)
Microspore-derived embryos produced from cork oak anther cultures after long-term incubations (up to 10-12 months) were analysed in order to determine the genetic variability and ploidy level stability, as well as morphology, developmental pattern and cellular organisation. Most of the embryos from long-term anther cultures were haploid (90.7%), corresponding to their microspore origin. The presence of a low percentage of diploid embryos (7.4%) was observed. Microsatellite analysis of haploid embryos, indicated different microspores origins of the same anther. In the diploid embryos, homozygosity for different alleles was detected from anther wall tissues, excluding the possibility of clonal origin. The maintenance of a high proportion of haploid embryos, in long-term anther cultures, is similar in percentage to that reported in embryos originating after 20 days of plating (Bueno et al. 1997). This suggests that no significant alterations in the ploidy level occurred during long incubations (up to 12 months). These results suggest that ploidy changes are rare in this in vitro system, and do not significantly increase during long-term cultures. Microscopical studies of the microspore embryos in various stages revealed a healthy and well developed anatomy with no aberrant or chimeric structures. The general morphology of embryos appearing at different times after plating, looked similar to that of earlier embryos, as well as the zygotic embryos, indicating that they represent high quality material for cork oak breeding.
Keywords: Cytochemistry; DNA-Analysis; flow cytometry; haploid embryos; immunocyto- chemistry; Quercus suber L.

Microspore-derived embryos from Quercus suber anthers mimic zygotic embryos and maintain haploidy in long-term anther culture. - Bueno, María a; Gomez, Arancha; Sepulveda, Federico; Seguí, José M.; Testillano, Pilar S.; Manzanera, Jose a; Risueño, Maria-Carmen (Journal of plant physiology, 2003)
Microspore-derived embryos produced from cork oak anther cultures after long-term incubations (up to 10-12 months) were analysed in order to determine the genetic variability and ploidy level stability, as well as morphology, developmental pattern and cellular organisation. Most of the embryos from long-term anther cultures were haploid (90.7%), corresponding to their microspore origin. The presence of a low percentage of diploid embryos (7.4%) was observed. Microsatellite analysis of haploid embryos, indicated different microspores origins of the same anther. In the diploid embryos, homozygosity for different alleles was detected from anther wall tissues, excluding the possibility of clonal origin. The maintenance of a high proportion of haploid embryos, in long-term anther cultures, is similar in percentage to that reported in embryos originating after 20 days of plating (Bueno et al. 1997). This suggests that no significant alterations in the ploidy level occurred during long incubations (up to 12 months). These results suggest that ploidy changes are rare in this in vitro system, and do not significantly increase during long-term cultures. Microscopical studies of the microspore embryos in various stages revealed a healthy and well developed anatomy with no aberrant or chimeric structures. The general morphology of embryos appearing at different times after plating, looked similar to that of earlier embryos, as well as the zygotic embryos, indicating that they represent high quality material for cork oak breeding.
The following values have no corresponding Zotero field: accession-num: 12964871
Keywords: Cytochemistry; DNA-Analysis; flow cytometry; haploid embryos; immunocyto- chemistry; Quercus suber L.

Monitoring Leaf Area Index of Mediterranean oak woodlands: Comparison of remotely-sensed estimates with simulations from an ecological process-based model - Garson, D Caraux; Lacaze, B (International Journal of Remote Sensing, 2003)
Annual vegetation abundance mapping was carried out within the DeMon II European project over a period of 12 years (1984-1996). The project relied on advanced satellite-based methods for spatial and temporal monitoring of Mediterranean oak woodlands by means of a series of Landsat Thematic Mapper (TM) satellite data. A standardized approach developed previously focuses on the Languedoc site, Hautes Garrigues, a typical sensitive Mediterranean region, but now recovering after centuries of grazing and agricultural activities. After geometric and radiometric rectification of nine full Landsat TM scenes with a refined correction in a smaller area of 75 km 2 75 km, a GIS database was created containing satellite data, thematic maps of vegetation, geological maps, climatic data and field measurements. An empirical relation between radiometric ground truth measurements and satellite derived Normalized Difference Vegetation Index (NDVI) allows us to derive Leaf Area Index (LAI). An ecological process-based model (Forest BGC) has been adapted to simulate ecosystem processes in a satisfying way at a local scale. Consistent results were obtained from remote sensing data and from simulations at a local scale, suggesting the possible use of remote-sensing data to monitor vegetation abundance changes at a regional scale. Without considering human disturbances, it can be noted that not much variation of LAI induced by natural factors can be detected over the considered 12-year period.
doi: 10.1080/0143116021000024267
Keywords: Annual variation (voyant); green vegetation; Leaf area index (LAI); NDVI; Oak woodlands; Remote sensing

Monitoring Leaf Area Index of Mediterranean oak woodlands: Comparison of remotely-sensed estimates with simulations from an ecological process-based model - Garson, D. Caraux; LACAZE, B. (International Journal of Remote Sensing, 2003)
Annual vegetation abundance mapping was carried out within the DeMon II European project over a period of 12 years (1984-1996). The project relied on advanced satellite-based methods for spatial and temporal monitoring of Mediterranean oak woodlands by means of a series of Landsat Thematic Mapper (TM) satellite data. A standardized approach developed previously focuses on the Languedoc site, Hautes Garrigues, a typical sensitive Mediterranean region, but now recovering after centuries of grazing and agricultural activities. After geometric and radiometric rectification of nine full Landsat TM scenes with a refined correction in a smaller area of 75 km 2 75 km, a GIS database was created containing satellite data, thematic maps of vegetation, geological maps, climatic data and field measurements. An empirical relation between radiometric ground truth measurements and satellite derived Normalized Difference Vegetation Index (NDVI) allows us to derive Leaf Area Index (LAI). An ecological process-based model (Forest BGC) has been adapted to simulate ecosystem processes in a satisfying way at a local scale. Consistent results were obtained from remote sensing data and from simulations at a local scale, suggesting the possible use of remote-sensing data to monitor vegetation abundance changes at a regional scale. Without considering human disturbances, it can be noted that not much variation of LAI induced by natural factors can be detected over the considered 12-year period.
doi: 10.1080/0143116021000024267doi: 10.1080/0143116021000024267The following values have no corresponding Zotero field: publisher: Taylor & Francis
Keywords: Annual variation (voyant); green vegetation; Leaf area index (LAI); NDVI; Oak woodlands; Remote sensing

Patterns of structural complexity and human disturbance of riparian vegetation in agricultural landscapes of a Mediterranean area - Corbacho, Casimiro; Sánchez, Juan Manuel; Costillo, Emilio (Agriculture, Ecosystems & Environment, 2003)
Riparian corridors are valuable high diversity habitats in Mediterranean-type environments and mainly in agricultural landscapes. Following a ‘vegetation complexes’ approach along ﬂuvial landscapes, the factors affecting structural complexity and human disturbance through agricultural areas in south-west (SW) Spain were analysed. Using principal component analysis and a stepwise multiple regression analysis three main results were obtained: (1) a successional vegetative gradient was noted from upper (pioneer herbaceous communities) to lower reaches of streams (closed-canopy forests) with a concomitant increase in both woody cover and habitat diversity; (2) land-use intensity associated with each of the agricultural production methods, which was mainly related to topographic irregularity, appeared to be the main cause of human disturbance in riparian areas. Thus, the closed-canopy forests located in ﬂat landscapes of lower streams were removed, highly modiﬁed or extensively fragmented; in contrast, riparian complexes placed on wild and rough landscapes of upper streams appeared as undisturbed or near-natural; (3) nearly 50% of the natural riparian vegetation of the study area has been highly modiﬁed or has disappeared, in most cases replaced by non-natural formations which have today become dominant. The protection of the few existing well-preserved riparian corridors and the restoration of highly altered riparian areas in the lower reaches of streams has become a priority in maintaining biodiversity in these agricultural Mediterranean landscapes. The extensive and cost-effective method developed for this study would be easily applicable to other large areas to evaluate the effect of human disturbance on riparian corridors
Keywords: agricultural landscapes; conservation; Human disturbance; Mediterranean areas; Riparian vegetation; Successional vegetative gradient; SW Spain

Patterns of structural complexity and human disturbance of riparian vegetation in agricultural landscapes of a Mediterranean area - Corbacho, Casimiro; Sánchez, Juan Manuel; Costillo, Emilio (Agriculture, Ecosystems & Environment, 2003)
Riparian corridors are valuable high diversity habitats in Mediterranean-type environments and mainly in agricultural landscapes. Following a ‘vegetation complexes’ approach along ﬂuvial landscapes, the factors affecting structural complexity and human disturbance through agricultural areas in south-west (SW) Spain were analysed. Using principal component analysis and a stepwise multiple regression analysis three main results were obtained: (1) a successional vegetative gradient was noted from upper (pioneer herbaceous communities) to lower reaches of streams (closed-canopy forests) with a concomitant increase in both woody cover and habitat diversity; (2) land-use intensity associated with each of the agricultural production methods, which was mainly related to topographic irregularity, appeared to be the main cause of human disturbance in riparian areas. Thus, the closed-canopy forests located in ﬂat landscapes of lower streams were removed, highly modiﬁed or extensively fragmented; in contrast, riparian complexes placed on wild and rough landscapes of upper streams appeared as undisturbed or near-natural; (3) nearly 50% of the natural riparian vegetation of the study area has been highly modiﬁed or has disappeared, in most cases replaced by non-natural formations which have today become dominant. The protection of the few existing well-preserved riparian corridors and the restoration of highly altered riparian areas in the lower reaches of streams has become a priority in maintaining biodiversity in these agricultural Mediterranean landscapes. The extensive and cost-effective method developed for this study would be easily applicable to other large areas to evaluate the effect of human disturbance on riparian corridors
Keywords: agricultural landscapes; conservation; Human disturbance; Mediterranean areas; Riparian vegetation; Successional vegetative gradient; SW Spain