<?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></contributors><titles><title><style face="normal" font="default" size="100%">Drought enhances folivory by shifting foliar metabolomes in Quercus ilex trees.</style></title><secondary-title><style face="normal" font="default" size="100%">The New phytologist</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2014</style></year></dates><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">At the molecular level, folivory activity on plants has mainly been related to the foliar concentrations of nitrogen (N) and/or particular metabolites. We studied the responses of different nutrients and the whole metabolome of Quercus ilex to seasonal changes and to moderate field experimental conditions of drought, and how this drought may affect folivory activity, using stoichiometric and metabolomic techniques. Foliar potassium (K) concentrations increased in summer and consequently led to higher foliar K : phosphorus (P) and lower carbon (C) : K and N : K ratios. Foliar N : P ratios were not lowest in spring as expected by the growth rate hypothesis. Trees exposed to moderate drought presented higher concentrations of total sugars and phenolics and these trees also experienced more severe folivory attack. The foliar increases in K, sugars and antioxidant concentrations in summer, the driest Mediterranean season, indicated enhanced osmoprotection under natural drought conditions. Trees under moderate drought also presented higher concentrations of sugars and phenolics; a plant response to avoid water loss. These shifts in metabolism produced an indirect relationship between increased drought and folivory activity.</style></abstract><accession-num><style face="normal" font="default" size="100%">24443979</style></accession-num></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Field-simulated droughts affect elemental leaf stoichiometry in Mediterranean forests and shrublands</style></title><secondary-title><style face="normal" font="default" size="100%">ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2013</style></year></dates><publisher><style face="normal" font="default" size="100%">GAUTHIER-VILLARS/EDITIONS ELSEVIER</style></publisher><pub-location><style face="normal" font="default" size="100%">23 RUE LINOIS, 75015 PARIS, FRANCE</style></pub-location><volume><style face="normal" font="default" size="100%">50</style></volume><pages><style face="normal" font="default" size="100%">20-31</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">This study evaluated the change induced by the year season and by experimentally induced drought on foliar element stoichiometry of the predominant woody species (Quercus ilex and Erica multiflora) in two Mediterranean ecosystems, a forest and a shrubland. This study is based in two long-term (11 yr) field experiments that simulated drought throughout the annual cycle. The effects of experimental droughts were significant but weaker than the changes produced by ontogeny and seasonality. Leaf N and P concentrations were higher in spring (the main growing season) in E. multiflora and, in Q. ilex in autumn (a period of additional growth). Leaf N:P ratios were lower in spring. In Q. ilex, the highest leaf K concentrations and leaf K:P ratios, and the lowest leaf C:K and N:K ratios, occurred in summer, the season when water stress was greatest. In E. multiflora, leaf K concentrations and K:P ratios were highest, and leaf C:K and N:K ratios were lowest in the plants from the drought-treated plots. The plant capacity to change K concentrations in response to seasonality and to drought is at least as great as the capacity to change N and P concentrations. The results underscore the importance of K and its stoichiometry relative to C, N and P in dry environments. These results indicate first, that N:P ratio shifts are not uniquely related to growth rate in Mediterranean plants but also to drought, and second, that there is a need to take into account K in ecological stoichiometry studies of terrestrial plants. (C) 2013 Elsevier Masson SAS. All rights reserved.</style></abstract></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Changes in water content and distribution in Quercus ilex leaves during progressive drought assessed by in vivo 1H magnetic resonance imaging.</style></title><secondary-title><style face="normal" font="default" size="100%">BMC plant biology</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2010</style></year></dates><publisher><style face="normal" font="default" size="100%">BioMed Central</style></publisher><volume><style face="normal" font="default" size="100%">10</style></volume><pages><style face="normal" font="default" size="100%">188</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Drought is a common stressor in many regions of the world and current climatic global circulation models predict further increases in warming and drought in the coming decades in several of these regions, such as the Mediterranean basin. The changes in leaf water content, distribution and dynamics in plant tissues under different soil water availabilities are not well known. In order to fill this gap, in the present report we describe our study withholding the irrigation of the seedlings of Quercus ilex, the dominant tree species in the evergreen forests of many areas of the Mediterranean Basin. We have monitored the gradual changes in water content in the different leaf areas, in vivo and non-invasively, by 1H magnetic resonance imaging (MRI) using proton density weighted (rhow) images and spin-spin relaxation time (T2) maps.</style></abstract><accession-num><style face="normal" font="default" size="100%">20735815</style></accession-num><notes><style face="normal" font="default" size="100%">From Duplicate 1 ( Changes in water content and distribution in Quercus ilex leaves during progressive drought assessed by in vivo 1H magnetic resonance imaging. - Sardans, Jordi; Peñuelas, Josep; Lope-Piedrafita, Silvia )</style></notes><research-notes><style face="normal" font="default" size="100%">From Duplicate 1 ( Changes in water content and distribution in Quercus ilex leaves during progressive drought assessed by in vivo 1H magnetic resonance imaging. - Sardans, Jordi; Peñuelas, Josep; Lope-Piedrafita, Silvia )</style></research-notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Drought, warming and soil fertilization effects on leaf volatile terpene concentrations in Pinus halepensis and Quercus ilex</style></title><secondary-title><style face="normal" font="default" size="100%">Acta Physiologiae Plantarum</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2008</style></year></dates><volume><style face="normal" font="default" size="100%">31</style></volume><pages><style face="normal" font="default" size="100%">207-218</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The changes in foliar concentrations of volatile terpenes in response to water stress, fertilization and temperature were analyzed in Pinus halepensis and Quercus ilex. The most abundant terpenes found in both species were a-pinene and D 3 -carene. b-Pinene and myrcene were also abundant in both species. P. halepensis concentrations were much greater than those of Q. ilex in agreement with the lack of storage in the latter species (15205.60 ± 1140.04 vs. 0.54 ± 0.08 lg g -1 [d.m.]). The drought treatment (reduction to 1/3 of full watering) signiﬁcantly increased the total terpene concentrations in both species (54% in P. halepensis and 119% in Q. ilex). The fertilization treatment (addition of either 250 kg N ha -1 or 250 kg P ha -1 or both) had no signiﬁcant effects on terpene foliar concentrations. The terpene concentrations increased from 0.25 lg g -1 [d.m.] at 30C to 0.70 lg g -1 [d.m.] at 40C in Q. ilex (the non-storing species) and from 2,240 lg g -1 [d.m.] at 30C to 15,621 lg g -1 [d.m.] at 40C in P. halepensis (the storing species). Both species presented negative relationship between terpene concentrations and relative water contents (RWC). The results of this study show that higher terpene concentrations can be expected in the warmer and drier conditions predicted for the next decades in the Mediterranean region.</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%">Blanch, Josep-salvador</style></author><author><style face="normal" font="default" size="100%">Penuelas, Josep</style></author><author><style face="normal" font="default" size="100%">Sardans, Jordi</style></author><author><style face="normal" font="default" size="100%">Llusia, Joan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Drought, warming and soil fertilization effects on leaf volatile terpene concentrations in Pinus halepensis and Quercus ilex</style></title><secondary-title><style face="normal" font="default" size="100%">Acta Physiologiae Plantarum</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">fertilization</style></keyword><keyword><style  face="normal" font="default" size="100%">Pinus halepensis</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Temperature</style></keyword><keyword><style  face="normal" font="default" size="100%">terpene concentration</style></keyword><keyword><style  face="normal" font="default" size="100%">water stress</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/s11738-008-0221-z</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">31</style></volume><pages><style face="normal" font="default" size="100%">207 - 218</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">The changes in foliar concentrations of volatile terpenes in response to water stress, fertilization and temperature were analyzed in Pinus halepensis and Quercus ilex. The most abundant terpenes found in both species were a-pinene and D 3 -carene. b-Pinene and myrcene were also abundant in both species. P. halepensis concentrations were much greater than those of Q. ilex in agreement with the lack of storage in the latter species (15205.60 ± 1140.04 vs. 0.54 ± 0.08 lg g -1 [d.m.]). The drought treatment (reduction to 1/3 of full watering) signiﬁcantly increased the total terpene concentrations in both species (54% in P. halepensis and 119% in Q. ilex). The fertilization treatment (addition of either 250 kg N ha -1 or 250 kg P ha -1 or both) had no signiﬁcant effects on terpene foliar concentrations. The terpene concentrations increased from 0.25 lg g -1 [d.m.] at 30C to 0.70 lg g -1 [d.m.] at 40C in Q. ilex (the non-storing species) and from 2,240 lg g -1 [d.m.] at 30C to 15,621 lg g -1 [d.m.] at 40C in P. halepensis (the storing species). Both species presented negative relationship between terpene concentrations and relative water contents (RWC). The results of this study show that higher terpene concentrations can be expected in the warmer and drier conditions predicted for the next decades in the Mediterranean region.</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%">Sardans, Jordi</style></author><author><style face="normal" font="default" size="100%">Penuelas, Josep</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Introduction of the factor of partitioning in the lithogenic enrichment factors of trace element bioaccumulation in plant tissues.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental monitoring and assessment</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">biomass</style></keyword><keyword><style  face="normal" font="default" size="100%">Bryopsida</style></keyword><keyword><style  face="normal" font="default" size="100%">Bryopsida: chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Bryopsida: growth &amp; development</style></keyword><keyword><style  face="normal" font="default" size="100%">Environmental Monitoring</style></keyword><keyword><style  face="normal" font="default" size="100%">Environmental Monitoring: methods</style></keyword><keyword><style  face="normal" font="default" size="100%">Plant Leaves</style></keyword><keyword><style  face="normal" font="default" size="100%">Plant Leaves: chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Plant Leaves: growth &amp; development</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus: chemistry</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus: growth &amp; development</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil Pollutants</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil Pollutants: analysis</style></keyword><keyword><style  face="normal" font="default" size="100%">Spain</style></keyword><keyword><style  face="normal" font="default" size="100%">Trace Elements</style></keyword><keyword><style  face="normal" font="default" size="100%">Trace Elements: analysis</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2006///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.ncbi.nlm.nih.gov/pubmed/16648953</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">115</style></volume><pages><style face="normal" font="default" size="100%">473 - 98</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Bioindicators are widely used in the study of trace elements inputs into the environment and great efforts have been conducted to separate atmospheric from soil borne inputs on biomass accumulation. Many monitoring studies of trace element pollution take into account the dust particles located in the plant surface plus the contents of the plant tissues. However, it is usually only the trace element content in the plant tissues that is relevant on plant health. Enrichment factor equations take into account the trace element enrichment of biomasses with respect soil or bedrocks by comparing the ratios of the trace element in question to a lithogenic element, usually Al. However, the enrichment equations currently in use are inadequate because they do not take into account the fact that Al (or whichever reference element) and the element in question may have different solubility-absorption-retention levels depending on the rock and soil types involved. This constrain will become critical when results from different sites are compared and so in this article we propose that the solubility factors of each element are taken into account in order to overcome this constrain. We analysed Sb, Co, Ni, Cr, Pb, Cd, Mn, V, Zn, Cu, As, Hg, and Al concentration in different zones of Catalonia (NE Spain) using the evergreen oak Quercus ilex and the moss Hypnum cupressiforme as target species. We compared the results obtained in rural and non industrial areas with those from the Barcelona Metropolitan Area. We observed differences in Al concentrations of soils and bedrocks at each different site, together with the differences in solubility between Al and the element in question, and a weak correlation between total soil content and water extract content through different sites for most trace elements. All these findings show the unsuitability of the current enrichment factors for calculating lithospheric and atmospheric contributions to trace element concentrations in biomass tissues. The trace element enrichment factors were calculated by subtracting the part predicted by substrate composition (deduced from water extracts from soils and bedrock) from total concentrations. Results showed that for most of the trace elements analysed, trace elements enrichment factors were higher inside the Barcelona Metropolitan Area than outside, a finding that indicates that greater atmospheric inputs occur in urban areas. The results show that the most useful and correct way of establishing a reference for lithospheric and atmospheric inputs into the plant tissues is, first, to analyse samples of the same plant species collected from a number of sites possessing similar environmental conditions (climate, vegetation type, soil type) and, second, to use this new enrichment factor obtained by subtracting from the total concentration in plant tissue the predicted contribution of soil or bedrock extracts instead of that of total soil or bedrock concentrations.</style></abstract><issue><style face="normal" font="default" size="100%">1-3</style></issue><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;accession-num: 16648953</style></notes></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Introduction of the factor of partitioning in the lithogenic enrichment factors of trace element bioaccumulation in plant tissues.</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental monitoring and assessment</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2006</style></year></dates><volume><style face="normal" font="default" size="100%">115</style></volume><pages><style face="normal" font="default" size="100%">473-98</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Bioindicators are widely used in the study of trace elements inputs into the environment and great efforts have been conducted to separate atmospheric from soil borne inputs on biomass accumulation. Many monitoring studies of trace element pollution take into account the dust particles located in the plant surface plus the contents of the plant tissues. However, it is usually only the trace element content in the plant tissues that is relevant on plant health. Enrichment factor equations take into account the trace element enrichment of biomasses with respect soil or bedrocks by comparing the ratios of the trace element in question to a lithogenic element, usually Al. However, the enrichment equations currently in use are inadequate because they do not take into account the fact that Al (or whichever reference element) and the element in question may have different solubility-absorption-retention levels depending on the rock and soil types involved. This constrain will become critical when results from different sites are compared and so in this article we propose that the solubility factors of each element are taken into account in order to overcome this constrain. We analysed Sb, Co, Ni, Cr, Pb, Cd, Mn, V, Zn, Cu, As, Hg, and Al concentration in different zones of Catalonia (NE Spain) using the evergreen oak Quercus ilex and the moss Hypnum cupressiforme as target species. We compared the results obtained in rural and non industrial areas with those from the Barcelona Metropolitan Area. We observed differences in Al concentrations of soils and bedrocks at each different site, together with the differences in solubility between Al and the element in question, and a weak correlation between total soil content and water extract content through different sites for most trace elements. All these findings show the unsuitability of the current enrichment factors for calculating lithospheric and atmospheric contributions to trace element concentrations in biomass tissues. The trace element enrichment factors were calculated by subtracting the part predicted by substrate composition (deduced from water extracts from soils and bedrock) from total concentrations. Results showed that for most of the trace elements analysed, trace elements enrichment factors were higher inside the Barcelona Metropolitan Area than outside, a finding that indicates that greater atmospheric inputs occur in urban areas. The results show that the most useful and correct way of establishing a reference for lithospheric and atmospheric inputs into the plant tissues is, first, to analyse samples of the same plant species collected from a number of sites possessing similar environmental conditions (climate, vegetation type, soil type) and, second, to use this new enrichment factor obtained by subtracting from the total concentration in plant tissue the predicted contribution of soil or bedrock extracts instead of that of total soil or bedrock concentrations.</style></abstract><accession-num><style face="normal" font="default" size="100%">16648953</style></accession-num></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%">Sardans, Jordi</style></author><author><style face="normal" font="default" size="100%">Penuelas, Josep</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Increasing drought decreases phosphorus availability in an evergreen Mediterranean forest</style></title><secondary-title><style face="normal" font="default" size="100%">Plant and Soil</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">climate change</style></keyword><keyword><style  face="normal" font="default" size="100%">Drought</style></keyword><keyword><style  face="normal" font="default" size="100%">Mediterranean ecosystems</style></keyword><keyword><style  face="normal" font="default" size="100%">mineralomasses</style></keyword><keyword><style  face="normal" font="default" size="100%">nutrient concentrations</style></keyword><keyword><style  face="normal" font="default" size="100%">nutrient cycles</style></keyword><keyword><style  face="normal" font="default" size="100%">phosphorus</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus ilex</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2004</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2004///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.springerlink.com/index/10.1007/s11104-005-0172-8</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">267</style></volume><pages><style face="normal" font="default" size="100%">367 - 377</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">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</style></abstract><issue><style face="normal" font="default" size="100%">1-2</style></issue></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors></contributors><titles><title><style face="normal" font="default" size="100%">Increasing drought decreases phosphorus availability in an evergreen Mediterranean forest</style></title><secondary-title><style face="normal" font="default" size="100%">Plant and Soil</style></secondary-title></titles><dates><year><style  face="normal" font="default" size="100%">2004</style></year></dates><volume><style face="normal" font="default" size="100%">267</style></volume><pages><style face="normal" font="default" size="100%">367-377</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">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</style></abstract></record></records></xml>