<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ruiz-Peinado, R</style></author><author><style face="normal" font="default" size="100%">Moreno, G</style></author><author><style face="normal" font="default" size="100%">Juarez, E</style></author><author><style face="normal" font="default" size="100%">Montero, G</style></author><author><style face="normal" font="default" size="100%">Roig, S</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The contribution of two common shrub species to aboveground and belowground carbon stock in Iberian dehesas</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Arid Environments</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Agro-silvo-pastoral system</style></keyword><keyword><style  face="normal" font="default" size="100%">biomass</style></keyword><keyword><style  face="normal" font="default" size="100%">carbon balance</style></keyword><keyword><style  face="normal" font="default" size="100%">Cistus ladanifer</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword><keyword><style  face="normal" font="default" size="100%">Root:shoot ratio</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year></dates><publisher><style face="normal" font="default" size="100%">Elsevier Ltd</style></publisher><volume><style face="normal" font="default" size="100%">91</style></volume><pages><style face="normal" font="default" size="100%">22-30</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Shrubs play an important role in water-limited agro-silvo-pastoral systems by providing shelter and forage for livestock, for erosion control, to maintain biodiversity, diversifying the landscape, and above all, facilitating the regeneration of trees. Furthermore, the carbon sink capacity of shrubs could also help to mitigate the effects of climate change since they constitute a high proportion of total plant biomass. The contribution of two common extensive native shrub species (Cistus ladanifer L. and Retama sphaerocarpa (L.) Boiss.) to the carbon pool of Iberian dehesas (Mediterranean agro-silvo-pastoral systems) is analyzed through biomass models developed at both individual (biovolume depending) and community level (height and cover depending). The total amount of carbon stored in these shrubs, including above- and belowground biomass, ranges from 1.8 to 11.2 Mg C ha 1 (mean 6.8 Mg C ha 1 ) for communities of C. ladanifer and from 2.6 to 8.6 Mg C ha 1 (mean 4.5 Mg C ha 1 ) for R. sphaerocarpa. These quantities account for over 20e30% of the total plant biomass in the system. The potential for carbon sequestration of these shrubs in the studied system ranges 0.10e1.32 Mg C ha 1 year 1 and 0.25e1.25 Mg C ha 1 year 1 for the C. ladanifer and R. sphaerocarpa communities’ respectively</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">LÓPEZ DÍAZ, M. L.</style></author><author><style face="normal" font="default" size="100%">ROLO, V.</style></author><author><style face="normal" font="default" size="100%">Moreno, G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Matorralización de la dehesa: implicaciones en la productividad total del sistema</style></title><secondary-title><style face="normal" font="default" size="100%">VI Congreso Forestal Español</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">bellota</style></keyword><keyword><style  face="normal" font="default" size="100%">Cistus ladanifer</style></keyword><keyword><style  face="normal" font="default" size="100%">producción de pasto</style></keyword><keyword><style  face="normal" font="default" size="100%">ramoneo</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2013///</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">1 - 12</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">La dehesa ha sido tradicionalmente un sistema muy diverso en el que, además de los pastos naturales y cultivos periódicos, han existido manchas de monte y zonas de arbolado claro con matorral. Existen cada vez más evidencias científicas y técnicas del papel positivo que puede jugar el matorral en la dehesa, principalmente en la regeneración del arbolado. Sin embargo, la matorralización de la dehesa puede tener consecuencias en la productividad total del sistema. El objetivo de este ensayo es evaluar los efectos de la matorralización en los diferentes recursos forrajeros de la dehesa: producción de bellota, ramón (proveniente del arbolado y matorral) y pasto herbáceo, así como sobre la Energía metabolizable. El estudio se ha enfocado en dos tipos de matorral que presentan comportamientos muy contrastados en términos de uso de recursos edáficos: jaral (Cistus ladanifer L.) y retamal (Retama sphaerocarpa (L.) Boiss.). Para ello, se tomaron muestras de los diferentes recursos forrajeros entre 2007 y 2010 en 40 dehesas. La presencia de jara redujo la productividad total de la dehesa, debido al efecto negativo que provoca sobre la producción de bellotas y pasto herbáceo y que no lleva a compensarse con el ramoneo. En cambio, se observó un efecto facilitador de la retama que dio lugar a una mejora en la productividad del sistema.</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;periodical: VI Congreso Forestal Español&lt;br/&gt;pub-location: Vitoria</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rolo, Víctor</style></author><author><style face="normal" font="default" size="100%">Plieninger, Tobias</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author></authors><secondary-authors><author><style face="normal" font="default" size="100%">Zobel, Martin</style></author></secondary-authors></contributors><titles><title><style face="normal" font="default" size="100%">Facilitation of holm oak recruitment through two contrasted shrubs species in Mediterranean grazed woodlands</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Vegetation Science</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cistus ladanifer</style></keyword><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">nurse plant</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword><keyword><style  face="normal" font="default" size="100%">Shrub encroachment</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><pages><style face="normal" font="default" size="100%">n/a--n/a</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Question: Regeneration failure and gradual tree dieback are major threats for the persistence of savanna-like grazed oak woodlands. Current research has argued that the scarcity of ‘safe sites’, in particular shrubs, is the main cause of the lack of effective tree recruitment. But can different shrub species be considered as safe sites generally? Do two distinct shrub species, with contrasted life strategies, affect several life stages of tree regeneration in similar ways or do they speciﬁcally inﬂuence the recruitment process? Location: Holm oak woodlands of SW Iberian Peninsula (40°02′ N, 06°06′ W). Methods: We surveyed densities of recently emerged and surviving seedlings as well as small and large saplings over two consecutive years in 40 sites that were independently managed, comparing plots encroached by either Cistus ladanifer (a shallow-rooted shrub, forming dense populations, with reported allelopathic compounds) or Retama sphaerocarpa (a N2-ﬁxing, deep-rooted shrub that forms scattered populations) vs their respective control plots (without shrubs). To assess the effect of mature trees and both shrub species on the performance and survival of recently emerged oak seedlings, we established an acorn sowing experiment in the same surveyed microhabitats (open spaces, shrub, tree and tree–shrub). Results: The survey showed that both shrubs species had a positive effect at early recruitment stages. At later life stages, this effect weakened under Cistus whereas it strengthened under Retama. The acorn sowing experiment showed that both shrub species buffered abiotic conditions and enhanced seedling functioning similarly, but Retama enhanced seedling survival to a higher extent than Cistus. Conclusions: The two shrub species impose a speciﬁc template that is able to affect the long-term dynamics of Mediterranean oak woodlands. Cistus shrubs are effective in protecting seedlings physically against herbivores and facilitate early survival, but may compete with older stages of oak regeneration. In contrast, Retama shrubs exert stronger biological facilitation and guarantee longterm persistence of surviving seedlings. We argue that improved understanding of the effectiveness of different nurse plants and their contrasting factors is of major interest for the conservation and restoration of degraded oak woodlands</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rolo, V</style></author><author><style face="normal" font="default" size="100%">Moreno, G</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Interspecific competition induces asymmetrical rooting profile adjustments in shrub-encroached open oak woodlands</style></title><secondary-title><style face="normal" font="default" size="100%">Trees</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cistus ladanifer</style></keyword><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">Niche separation</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword><keyword><style  face="normal" font="default" size="100%">Root plasticity</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2012</style></year></dates><volume><style face="normal" font="default" size="100%">26</style></volume><pages><style face="normal" font="default" size="100%">997-1006</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">It is recognized that the extent of woody encroachment is increasing worldwide, but less is known concerning the likely altered below-ground structure of cooccurring plants. The aim of this study was to analyze the root system plasticity of three layers of vegetation growing together (trees, shrubs and pasture) and identify potential mechanisms of competition avoidance. Root morphology and distribution of trees, pasture and two contrasting shrub species (deep and shallow rooted) were studied in open oak woodlands of south-western Spain. Soil samples were obtained from paired adjacent plots, with and without shrubs, by taking soil cores to a depth of 3 m. Analysis of tree and pasture root systems in the presence of shrubs revealed signiﬁcant reductions in root biomass and consistent increases in speciﬁc root length. Additionally, root proﬁles changed substantially, becoming signiﬁcantly deeper for trees and shallower for pasture. In contrast, both types of shrub increased their root biomass when growing in competition, but without signiﬁcantly modifying their rooting proﬁle. Shrubs seem to be stronger competitors for below-ground resources than neighboring species. However, trees and pasture show clear plastic responses to shrub presence, irrespective of their rooting patterns, probably to minimize competitive interactions and maximize resource acquisition.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rivest, David</style></author><author><style face="normal" font="default" size="100%">Rolo, Víctor</style></author><author><style face="normal" font="default" size="100%">López-Díaz, M Lourdes</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Belowground competition for nutrients in shrub-encroached Mediterranean dehesas</style></title><secondary-title><style face="normal" font="default" size="100%">Nutrient Cycling in Agroecosystems</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cistus ladanifer</style></keyword><keyword><style  face="normal" font="default" size="100%">Dry matter production</style></keyword><keyword><style  face="normal" font="default" size="100%">Native pasture</style></keyword><keyword><style  face="normal" font="default" size="100%">Nutrient uptake</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword><keyword><style  face="normal" font="default" size="100%">Silvopastoral systems</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year></dates><volume><style face="normal" font="default" size="100%">90</style></volume><pages><style face="normal" font="default" size="100%">347-354</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Managing multilayered silvopastoral systems such as Mediterranean dehesas requires the study of nutrient resource partitioning among coexisting species and determination to what extent soil nutrients are limiting plant growth. We determined the effects of NPK fertilisation maintained over two consecutive years on dry matter production and nutritional status of pasture (herbaceous) species, two shrub species and Quercus ilex L. in two silvopastoral sites with different shrub-layer species. We selected two prominent Mediterranean shrub species that vary in their speciﬁc ecological strategies: a N2-ﬁxing and sparse deep-rooting shrub (Retama sphaerocarpa (L.) Boiss, Retama site), and a dense shallow-rooting shrub (Cistus ladanifer L., Cistus site). Fertilisation signiﬁcantly (P B 0.05) increased pasture dry mass by 460% and 1,090% in the Retama and Cistus sites, respectively. Nitrogen uptake by pasture species was most stimulated in both sites, and was the major limiting nutrient for this group. At the Cistus site, fertilisation signiﬁcantly increased leaf dry mass of Q. ilex by 53%, but no signiﬁcant effect was found at the Retama site. There were no signiﬁcant effects of fertilisation treatments on dry mass and nutrient status of Retama cladodes and Cistus leaves. Vector analysis revealed that the magnitude of relative changes in nutrient uptake and dry matter production of pasture in response to fertilisation was markedly higher than that of Q. ilex, R. sphaerocarpa and C. ladanifer, suggesting high competitive ability of pasture species for soil nutrients. Results suggest that patterns of soil nutrient partitioning are site-speciﬁc and, thus, likely depend on the dominant species in the shrub layer</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Cuesta, Bárbara</style></author><author><style face="normal" font="default" size="100%">Villar-Salvador, Pedro</style></author><author><style face="normal" font="default" size="100%">Puértolas, Jaime</style></author><author><style face="normal" font="default" size="100%">Rey Benayas, José M.</style></author><author><style face="normal" font="default" size="100%">Michalet, Richard</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Facilitation of Quercus ilex in Mediterranean shrubland is explained by both direct and indirect interactions mediated by herbs</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Ecology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">chlorophyll fluorescence</style></keyword><keyword><style  face="normal" font="default" size="100%">herb competition</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword><keyword><style  face="normal" font="default" size="100%">seedling size</style></keyword><keyword><style  face="normal" font="default" size="100%">water potential</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1111/j.1365-2745.2010.01655.xhttp://doi.wiley.com/10.1111/j.1365-2745.2010.01655.x</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">98</style></volume><pages><style face="normal" font="default" size="100%">687 - 696</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">1. Competitive and facilitative interactions shape plant communities. Whereas a number of studies have addressed competition and direct facilitation among plants in dry ecosystems, indirect facilitation has received little attention. 2. We investigated the relative importance of direct and indirect facilitation by the nurse plant Retama sphaerocarpa on late-successional Quercus ilex seedlings mediated by herb suppression in a Mediterranean shrubland in 2006 and 2007. We also studied whether facilitation outcome depended on the size of the facilitated seedlings. 3. A field experiment was carried out to test the effect of (i) position of Q. ilex seedling with respect to shrub canopy (under shrubs or in gaps), (ii) herb competition (presence or absence), and (iii) seedling size. 2006 was an average rainfall year while 2007 had a much more humid spring and a dryer summer than 2006. 4. In both years, nurse shrubs reduced seedling mortality whereas herbs increased it. In the average rainfall year, seedling mortality under shrubs was unaffected by herbs whereas in gaps it was significantly higher in presence of herbs. This showed that the nurse shrub indirectly facilitated the seedlings by reducing the competitive capacity of herbs. Conversely, facilitation was predominately direct during the humid spring and dry summer year since herbs hindered seedling survival similarly under the nurse shrub and in gaps. The nurse shrub directly facilitated the seedlings by reducing seedling photoinhibition and water stress. 5. Improvement of environmental conditions by Retama benefited smaller seedlings but not larger seedlings since the nurse shrub reduced mortality of smaller seedlings relative to that in gaps, but this effect was not observed for larger seedlings. This indicates that individuals within a seedling population may not have the same response to facilitation. 6. Synthesis. Both indirect and direct facilitation are important mechanisms for Q. ilex regeneration in Retama shrubland and their importance seems to vary with climatic conditions. Indirect facilitation by release of herb competition under nurse shrubs is important in years of dry springs when competition between nurse shrubs and herbs is high, whereas direct facilitation mediated by microclimate amelioration increases with summer aridity.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;publisher: Blackwell Publishing Ltd</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">LÓPEZ DÍAZ, M. L.</style></author><author><style face="normal" font="default" size="100%">Moreno Marcos, G.</style></author><author><style face="normal" font="default" size="100%">ROLO ROMERO, V.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">INFLUENCIA DEL ARBOLADO Y MATORRAL EN EL CONTENIDO DE NITRÓGENO DEL PASTO HERBÁCEO EN LA DEHESA</style></title><secondary-title><style face="normal" font="default" size="100%">PASTOS: FUENTE NATURAL DE ENERGÍA 4ª Reunión Ibérica de Pastos y Forrajes</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">calidad del pasto</style></keyword><keyword><style  face="normal" font="default" size="100%">Cistus ladanifer</style></keyword><keyword><style  face="normal" font="default" size="100%">ornithopus compressus</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2010</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2010///</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">373 - 378</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The objective of this assay is to analyse the influence of tree and shrub presence on nitrogen concentration in different herbaceous species. Two shrub species are studied: Cistus ladanifer L. Re- tama sphaerocarpa (L.) Boiss. In Spring 2009, different species of grass (Avena sativa L.), legumes (Ornithopus compresus L.) and Asteraceae (Senecio vulgaris L. and Taraxacum officinale (Lam.) Schrank), during flowering state. They were sampled in different positions respect to tree and shrub. Tree and R. sphaerocarpa presence improved pasture quality. C. ladanifer shrub reduced the pasture nitrogen content. Ornithopus compresus L. was the most affected specie to the different treatments. Key words: Pasture quality, Cistus ladanifer, Retama sphaerocarpa, Ornithopus compressus</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;periodical: PASTOS: FUENTE NATURAL DE ENERGÍA 4ª Reunión Ibérica de Pastos y Forrajes</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>47</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">LÓPEZ DÍAZ, M. L.</style></author><author><style face="normal" font="default" size="100%">ROLO ROMERO, V.</style></author><author><style face="normal" font="default" size="100%">Moreno Marcos, G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Variación espacial del pasto herbáceo en la dehesa: interrelación árbol-pasto-matorral LÓPEZ</style></title><secondary-title><style face="normal" font="default" size="100%">V Congreso Forestal Español</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cistus ladanifer</style></keyword><keyword><style  face="normal" font="default" size="100%">competencia</style></keyword><keyword><style  face="normal" font="default" size="100%">forraje</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2009///</style></date></pub-dates></dates><pages><style face="normal" font="default" size="100%">1 - 10</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Los sistemas silvopastorales, y en concreto la dehesa, son ecosistemas muy complejos en los que se combina la producción de madera (a largo plazo) con la de pasto (anual), y que son el resultado de las interacciones existentes entre cuatro componentes: suelo, arbolado, pasto (herbáceo y arbustivo) y animales. En este tipo de sistemas, la mayoría de las decisiones irán encaminadas a potenciar las interacciones que resulten beneficiosas y evitar las negativas, por lo que es muy importante conocer su evolución en el tiempo. El objetivo de este trabajo es evaluar como varía la composición específica del pasto herbáceo en la dehesa según su localización respecto al arbolado y al matorral. El estudio se ha enfocado en los dos principales tipos de matorral presentes mayoritariamente en las dehesas extremeñas y que presentan comportamientos muy contrastados en términos de uso de recursos edáficos: jaral (Cistus ladanifer L.) y retamal (Retama sphaerocarpa (L.) Boiss.). Para ello, se colocaron jaulas de exclusión al pastoreo en seis fincas de dehesa (tres con presencia de jara y tres con retama), situadas a diversas distancias del arbolado (bajo, periferia y lejos) en zonas con y sin matorral. Se observó una mayor proporción de gramíneas debajo del arbolado y ligadas a la presencia de retama. En cambio, las leguminosas se vieron beneficiadas por la presencia de jara.</style></abstract><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;periodical: V Congreso Forestal Español</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lozano Parra, F. J.</style></author><author><style face="normal" font="default" size="100%">Schnabel, S.</style></author><author><style face="normal" font="default" size="100%">Ceballos Barbancho, A.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">DINÁMICA DEL AGUA DEL SUELO EN DEHESA BAJO DIFERENTES CUBIERTAS VEGETALES. RESULTADOS PRELIMINARES.</style></title><secondary-title><style face="normal" font="default" size="100%">Estudios en la Zona no Saturada del Suelo</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">bajo copa</style></keyword><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">humedad del suelo</style></keyword><keyword><style  face="normal" font="default" size="100%">pastizal</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus rotundifolia (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2008///</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">X</style></volume><pages><style face="normal" font="default" size="100%">47 - 52</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dehesa ecosystems, characterized by a disperse tree cover of the genus Quercus, constitute a resource of great importance in large parts of SW Iberian Peninsula. Generally these areas are conditioned by their environmental limits such as shallow soils, seasonal and intraannual rainfall variability, which determine the availability of water for plants. The main objective of the present work is the study of soil water dynamics in dehesas, explaining the effect of different vegetation covers and soil characteristics. Soil moisture is determined in 15 stations, distributed in three farms in Extremadura, each of them composed of sensors located at various depths which register soil moisture continuously with a time resolution of 30 minutes. The stations are distributed in open areas (pasture), below the canopy of the shrub Retama sphaerocarpa and below the canopy of Quercus rotundifolia. First results indicate complex soil water dynamics with contrasting situations at sites with the same vegetation cover, and showing that various situations may be produced in the same station during a hydrological year. Furthermore, the largest variations are observed in the upper soil layer, being soil moisture variations lowest at greater depth, independently of the vegetation cover.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lozano Parra, F J</style></author><author><style face="normal" font="default" size="100%">Schnabel, S</style></author><author><style face="normal" font="default" size="100%">Ceballos Barbancho, A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">DINÁMICA DEL AGUA DEL SUELO EN DEHESA BAJO DIFERENTES CUBIERTAS VEGETALES. RESULTADOS PRELIMINARES.</style></title><secondary-title><style face="normal" font="default" size="100%">Estudios en la Zona no Saturada del Suelo</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">bajo copa</style></keyword><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">humedad del suelo</style></keyword><keyword><style  face="normal" font="default" size="100%">pastizal</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus rotundifolia (voyant)</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year></dates><volume><style face="normal" font="default" size="100%">X</style></volume><pages><style face="normal" font="default" size="100%">47-52</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Dehesa ecosystems, characterized by a disperse tree cover of the genus Quercus, constitute a resource of great importance in large parts of SW Iberian Peninsula. Generally these areas are conditioned by their environmental limits such as shallow soils, seasonal and intraannual rainfall variability, which determine the availability of water for plants. The main objective of the present work is the study of soil water dynamics in dehesas, explaining the effect of different vegetation covers and soil characteristics. Soil moisture is determined in 15 stations, distributed in three farms in Extremadura, each of them composed of sensors located at various depths which register soil moisture continuously with a time resolution of 30 minutes. The stations are distributed in open areas (pasture), below the canopy of the shrub Retama sphaerocarpa and below the canopy of Quercus rotundifolia. First results indicate complex soil water dynamics with contrasting situations at sites with the same vegetation cover, and showing that various situations may be produced in the same station during a hydrological year. Furthermore, the largest variations are observed in the upper soil layer, being soil moisture variations lowest at greater depth, independently of the vegetation cover.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Lansac, A R</style></author><author><style face="normal" font="default" size="100%">ZABALLOS, J P</style></author><author><style face="normal" font="default" size="100%">Martin, A</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Seasonal water potential changes and proline accumulation in Mediterranean shrubland species</style></title><secondary-title><style face="normal" font="default" size="100%">Plant Ecology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cistus ladanifer</style></keyword><keyword><style  face="normal" font="default" size="100%">Genista hirsuta</style></keyword><keyword><style  face="normal" font="default" size="100%">Halimium viscosum</style></keyword><keyword><style  face="normal" font="default" size="100%">Juniperus oxycedrus</style></keyword><keyword><style  face="normal" font="default" size="100%">Lavandula pedunculata</style></keyword><keyword><style  face="normal" font="default" size="100%">Leaf mass per area</style></keyword><keyword><style  face="normal" font="default" size="100%">nitrogen</style></keyword><keyword><style  face="normal" font="default" size="100%">Proline</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus faginea</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus rotundifolia</style></keyword><keyword><style  face="normal" font="default" size="100%">Relative water content</style></keyword><keyword><style  face="normal" font="default" size="100%">retama sphaerocarpa</style></keyword><keyword><style  face="normal" font="default" size="100%">Thymus zygis</style></keyword><keyword><style  face="normal" font="default" size="100%">water potential</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1994</style></year></dates><volume><style face="normal" font="default" size="100%">113</style></volume><pages><style face="normal" font="default" size="100%">141-154</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We studied the water relations of 6 shrub and 3 tree species typical of the mediterranean climate region of central Spain to identify differential responses to water stress between and within species, and to determine if free proline concentration in leaves could be used as a water stress indicator. Predawn and midday water potentials (ffdw) on a seasonal basis, relative water content (RWC), leaf mass per area, foliar nitrogen and free proline concentrations were measured. The lowest water potentials were observed at the end of the summer, with recovery to higher water potentials in the fall and winter seasons. Species differed regarding the annual qdw fluctuation. Thymus zygis, Halimium viscosum, Genista hirsuta and Juniperus oxycedrus exhibited the most negative midday and predawn ~ w (both less than -6 MPa) with a large magnitude of response to changing conditions in soil moisture of the upper horizon of the soil. Lavandula pedunculata and Cistus ladanifer showed a moderate response. Quercus rotundifolia, Quercus faginea and Retama sphaerocarpa showed a modest response. The ~ w of different size individuals of Quercus rotundifolia and Cistus ladanifer were compared. The annual fflw fluctuation was greater in small individuals as compared to large individuals. In every species, there was an increase in proline concentration of bulk leaf tissues when predawn kVw dropped below -5 MPa. Small plants of Cistus ladanifer reached lower water potentials and also higher concentration of proline than bigger plants. Proline could possibly be used as a drought stress indicator in every species except Q. rotundifolia. It is suggested that in addition to water stress avoidance due to deep root systems, some mechanisms of water stress tolerance may operate among shrub and tree species of central Spain.</style></abstract></record></records></xml>