<?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%">Pulido, Fernando</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author><author><style face="normal" font="default" size="100%">Garcia, Eustolia</style></author><author><style face="normal" font="default" size="100%">Obrador, Jose J</style></author><author><style face="normal" font="default" size="100%">Bonal, Raul</style></author><author><style face="normal" font="default" size="100%">Díaz, Mario</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Resource manipulation reveals flexible allocation rules to growth and reproduction in a Mediterranean evergreen oak</style></title><secondary-title><style face="normal" font="default" size="100%">JOURNAL OF PLANT ECOLOGY</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">acorn abortion</style></keyword><keyword><style  face="normal" font="default" size="100%">allocational plasticity</style></keyword><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">growth-reproduction trade-offs</style></keyword><keyword><style  face="normal" font="default" size="100%">nutrient addition</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">resource allocation</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2014</style></year></dates><publisher><style face="normal" font="default" size="100%">OXFORD UNIV PRESS</style></publisher><pub-location><style face="normal" font="default" size="100%">GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND</style></pub-location><volume><style face="normal" font="default" size="100%">7</style></volume><pages><style face="normal" font="default" size="100%">77-85</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Aims In plants, resource allocation to growth and reproduction may depart from trade-off expectations if (i) investment in growth and reproduction relies on different resource pools, (ii) allocation to reproduction is dependent upon reaching some growth threshold or (iii) reproduction is developmentally linked to growth, both functions relying on the same resource pool. We examined the effects of enhanced resource level on patterns of resource allocation to growth and reproduction in holm oak (Quercus ilex sbsp. ballota), a Mediterranean evergreen tree. Methods In the experimental year (2003), we manipulated the amount of soil nutrients in autumn (to increase nutrient uptake during shoot elongation in the following spring) and soil water in summer (to increase water uptake during acorn growth). Indicators of growth and male and female reproduction were estimated in the pre-experimental (2002), experimental (2003) and post-experimental (2004) years. Important Findings Fertilized trees produced significantly longer shoots, but the number of female flowers per shoot was not affected by treatments. The production of male catkins was also enhanced by fertilization. Irrigation did not affect the production of female flowers or abortion rates. Growth and female reproduction showed no consistent relationship in untreated trees, but resource addition elicited a growth-female reproduction trade-off in the experimental year. The sign of this significant relationship changed in the post-experimental year, indicating the existence of lagged effects of resource manipulation on acorn production. Overall, patterns of allocation to growth and reproduction varied as a function of sex, resource availability and year, a result consistent with extreme allocational plasticity in holm oak.</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, 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%">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%">Cubera, Elena</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author><author><style face="normal" font="default" size="100%">Solla, Alejandro</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Quercus ilex root growth in response to heterogeneous conditions of soil bulk density and soil NH4-N content</style></title><secondary-title><style face="normal" font="default" size="100%">Soil and Tillage Research</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Oak decline</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Root density</style></keyword><keyword><style  face="normal" font="default" size="100%">Root depth</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil bulk density</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil NH4 content</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2009</style></year></dates><volume><style face="normal" font="default" size="100%">103</style></volume><pages><style face="normal" font="default" size="100%">16-22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A greenhouse study examined the effects of heterogeneous conditions of soil bulk density and soil NH4-N content on the growth of holm oak (Quercus ilex L.) seedlings over an 8-month period. Heterogeneity of soil was produced inside 150 cm depth pots, by applying manual compaction or enriching different soil layers with NH4 (vertical heterogeneity) and, by splitting the root system into two columns with differing soil bulk density or NH4 conditions (horizontal heterogeneity). Root distribution patterns were assessed by collecting roots within layers, each 10 cm depth, and by recording both the ﬁne (diameter &lt;2 mm) and the coarse (diameter 2 mm) root biomass. Root systems signiﬁcantly responded to the vertical gradients of soil bulk density, decreasing their maximum depth and showing lower values of ﬁne root densities at the layers with a dry bulk density of 1.62 Mg m3 . The split-root system showed that maximum rooting depth of the axis with a dry bulk density of 1.38 Mg m3 was limited by the reduced rooting depth of the adjacent more compacted axis. Root systems were less dense in the NH4 soil treatment than in the control soil treatment (34 mg dm3 vs. 212 mg dm3 ), even at the lowest rate used (0:1 g NH4 L 1 soil ). This high sensitivity to NH4 conducted to a signiﬁcant decrease of shoot height and root depth (50 and 43%, respectively). The split-root system showed that unfavourable conditions of NH4 content have local consequences on the rooting depth and systemic consequences on the ﬁne root density. The implications of root growth restrictions for Q. ilex natural regeneration, seedling survival, and decline are discussed.</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%">Cubera, Elena</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author><author><style face="normal" font="default" size="100%">Solla, Alejandro</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Quercus ilex root growth in response to heterogeneous conditions of soil bulk density and soil NH4-N content</style></title><secondary-title><style face="normal" font="default" size="100%">Soil and Tillage Research</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Oak decline</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Root density</style></keyword><keyword><style  face="normal" font="default" size="100%">Root depth</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil bulk density</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil NH4 content</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><urls><web-urls><url><style face="normal" font="default" size="100%">http://linkinghub.elsevier.com/retrieve/pii/S0167198708001724</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">103</style></volume><pages><style face="normal" font="default" size="100%">16 - 22</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">A greenhouse study examined the effects of heterogeneous conditions of soil bulk density and soil NH4-N content on the growth of holm oak (Quercus ilex L.) seedlings over an 8-month period. Heterogeneity of soil was produced inside 150 cm depth pots, by applying manual compaction or enriching different soil layers with NH4 (vertical heterogeneity) and, by splitting the root system into two columns with differing soil bulk density or NH4 conditions (horizontal heterogeneity). Root distribution patterns were assessed by collecting roots within layers, each 10 cm depth, and by recording both the ﬁne (diameter &lt;2 mm) and the coarse (diameter 2 mm) root biomass. Root systems signiﬁcantly responded to the vertical gradients of soil bulk density, decreasing their maximum depth and showing lower values of ﬁne root densities at the layers with a dry bulk density of 1.62 Mg m3 . The split-root system showed that maximum rooting depth of the axis with a dry bulk density of 1.38 Mg m3 was limited by the reduced rooting depth of the adjacent more compacted axis. Root systems were less dense in the NH4 soil treatment than in the control soil treatment (34 mg dm3 vs. 212 mg dm3 ), even at the lowest rate used (0:1 g NH4 L 1 soil ). This high sensitivity to NH4 conducted to a signiﬁcant decrease of shoot height and root depth (50 and 43%, respectively). The split-root system showed that unfavourable conditions of NH4 content have local consequences on the rooting depth and systemic consequences on the ﬁne root density. The implications of root growth restrictions for Q. ilex natural regeneration, seedling survival, and decline are discussed.</style></abstract><issue><style face="normal" font="default" size="100%">1</style></issue></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%">Montero, María Jesús</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author><author><style face="normal" font="default" size="100%">Bertomeu, Manuel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Light distribution in scattered-trees open woodlands in Western Spain</style></title><secondary-title><style face="normal" font="default" size="100%">Agroforestry Systems</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">allometric relationships</style></keyword><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">fish-eye photograph</style></keyword><keyword><style  face="normal" font="default" size="100%">light transmittance</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">radiation map</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><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/index/10.1007/s10457-008-9143-4</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">73</style></volume><pages><style face="normal" font="default" size="100%">233 - 244</style></pages><isbn><style face="normal" font="default" size="100%">1045700891434</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We have studied the percentage of radiation transmitted through the tree canopy to the underlying pasture and crops in dehesas of Southwest Spain by means of ﬁsh-eye photographs taken at different distances from the tree. Thirty-six trees were studied covering all the diametric classes (0.1–14 m canopy width) of two stands, with mean density of 19 mature trees ha -1 . Intercepted light decreased with distance following an logistic curve, indicating a rapid increase in the light availability with distance from the tree. For mature trees, radiation was constant beyond 20 m. Applying a multivariable regression light equation, distance, stem diameter and canopy width explained more than 88% of the light variability for each orientation studied. A simple model was built up from light equations, tree growth curves and allometric relationships. From this model, we have estimated that radiation available for crops and pasture decreased up to 21% due to the presence of trees in a standard dehesa with 24 mature trees ha -1 and 13% of canopy cover. In addition, we have generated different radiation maps of virtual dehesas differing in tree age, density and arrangement, which could be useful to determine optimal tree planting schemes and consequent pruning and thinning regimes.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue></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%">Montero, María Jesús</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author><author><style face="normal" font="default" size="100%">Bertomeu, Manuel</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Light distribution in scattered-trees open woodlands in Western Spain</style></title><secondary-title><style face="normal" font="default" size="100%">Agroforestry Systems</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">allometric relationships</style></keyword><keyword><style  face="normal" font="default" size="100%">Dehesa</style></keyword><keyword><style  face="normal" font="default" size="100%">fish-eye photograph</style></keyword><keyword><style  face="normal" font="default" size="100%">light transmittance</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">radiation map</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year></dates><volume><style face="normal" font="default" size="100%">73</style></volume><pages><style face="normal" font="default" size="100%">233-244</style></pages><isbn><style face="normal" font="default" size="100%">1045700891434</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We have studied the percentage of radiation transmitted through the tree canopy to the underlying pasture and crops in dehesas of Southwest Spain by means of ﬁsh-eye photographs taken at different distances from the tree. Thirty-six trees were studied covering all the diametric classes (0.1–14 m canopy width) of two stands, with mean density of 19 mature trees ha -1 . Intercepted light decreased with distance following an logistic curve, indicating a rapid increase in the light availability with distance from the tree. For mature trees, radiation was constant beyond 20 m. Applying a multivariable regression light equation, distance, stem diameter and canopy width explained more than 88% of the light variability for each orientation studied. A simple model was built up from light equations, tree growth curves and allometric relationships. From this model, we have estimated that radiation available for crops and pasture decreased up to 21% due to the presence of trees in a standard dehesa with 24 mature trees ha -1 and 13% of canopy cover. In addition, we have generated different radiation maps of virtual dehesas differing in tree age, density and arrangement, which could be useful to determine optimal tree planting schemes and consequent pruning and thinning regimes.</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%">Cubera, Elena</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author><author><style face="normal" font="default" size="100%">Elena, C.</style></author><author><style face="normal" font="default" size="100%">Gerardo, M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of single Quercus ilex trees upon spatial and seasonal changes in soil water content in dehesas of central western Spain</style></title><secondary-title><style face="normal" font="default" size="100%">Ann. For. Sci.</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Oak woodland</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil water content</style></keyword><keyword><style  face="normal" font="default" size="100%">TDR</style></keyword><keyword><style  face="normal" font="default" size="100%">tree-grass interaction</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2007</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2007///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://dx.doi.org/10.1051/forest:2007012</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">64</style></volume><pages><style face="normal" font="default" size="100%">355 - 364</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The spatial and temporal evolution of soil water content () in Quercus ilex dehesas has been investigated to determine how trees modify the soil water dynamics and the nature of tree-grass interactions in terms of soil water use in these ecosystems. Soil physical parameters and were measured at different distances from the tree trunk (2-30 m) in the upper 300 cm of soil. was measured monthly by TDR during 2002-2005. Tree water potential was determined during the summers of 2004 and 2005. At deeper soil layers, mean values were higher beyond than beneath tree canopy during dry periods. depletion beyond tree canopy continued even in summer, when herbaceous plants dried up, suggesting that trees uptake water from the whole inter-tree space. Results have shown a high dependence of trees on deep water reserves throughout late spring and summer, which helps to avoid competition for water with herbaceous vegetation.</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue></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%">Cubera, Elena</style></author><author><style face="normal" font="default" size="100%">Moreno, Gerardo</style></author><author><style face="normal" font="default" size="100%">Elena, C</style></author><author><style face="normal" font="default" size="100%">Gerardo, M</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of single Quercus ilex trees upon spatial and seasonal changes in soil water content in dehesas of central western Spain</style></title><secondary-title><style face="normal" font="default" size="100%">Ann. For. Sci.</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Oak woodland</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil water content</style></keyword><keyword><style  face="normal" font="default" size="100%">TDR</style></keyword><keyword><style  face="normal" font="default" size="100%">tree-grass interaction</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2007</style></year></dates><volume><style face="normal" font="default" size="100%">64</style></volume><pages><style face="normal" font="default" size="100%">355-364</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The spatial and temporal evolution of soil water content () in Quercus ilex dehesas has been investigated to determine how trees modify the soil water dynamics and the nature of tree-grass interactions in terms of soil water use in these ecosystems. Soil physical parameters and were measured at different distances from the tree trunk (2-30 m) in the upper 300 cm of soil. was measured monthly by TDR during 2002-2005. Tree water potential was determined during the summers of 2004 and 2005. At deeper soil layers, mean values were higher beyond than beneath tree canopy during dry periods. depletion beyond tree canopy continued even in summer, when herbaceous plants dried up, suggesting that trees uptake water from the whole inter-tree space. Results have shown a high dependence of trees on deep water reserves throughout late spring and summer, which helps to avoid competition for water with herbaceous vegetation.</style></abstract></record></records></xml>