<?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%">Recio, C</style></author><author><style face="normal" font="default" size="100%">Martin, Q</style></author><author><style face="normal" font="default" size="100%">Raposo, C</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">GC-C-IRMS analysis of FAMEs as a tool to ascertain the diet of Iberian pigs used for the production of pork products with high added value</style></title><secondary-title><style face="normal" font="default" size="100%">GRASAS Y ACEITES</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Cured ham</style></keyword><keyword><style  face="normal" font="default" size="100%">delta C-13</style></keyword><keyword><style  face="normal" font="default" size="100%">Quality assurance</style></keyword><keyword><style  face="normal" font="default" size="100%">Stable isotopes</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year></dates><publisher><style face="normal" font="default" size="100%">INST GRASA SUS DERIVADOS</style></publisher><pub-location><style face="normal" font="default" size="100%">AVDA-PADRE GARCIA TEJERO 4, 41012 SEVILLE, SPAIN</style></pub-location><volume><style face="normal" font="default" size="100%">64</style></volume><pages><style face="normal" font="default" size="100%">181-190</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Taste, quality and perceived health benefits result in a high demand for both green and mature pork products derived from the Iberian bred swine. These characteristics are directly related to diet and breeding style (free ranging in a particular Mediterranean ecosystem: the Dehesa). Given that current demand is not matched by the available resources, animal feed is increasingly used. GC-C-IRMS analysis of Palmitic, Stearic, Oleic and Linoleic Acid methyl esters allows for differentiating between pork raised in the traditional way and that fattened on animal feed. Although a value of delta C-13(C18:1) = -25.9 parts per thousand is a good discriminator, exploratory analysis of principal canonical components is required to properly assign any unknown sample.</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%">David, Teresa S.</style></author><author><style face="normal" font="default" size="100%">Pinto, Clara A.</style></author><author><style face="normal" font="default" size="100%">Nadezhdina, Nadezhda</style></author><author><style face="normal" font="default" size="100%">Kurz-Besson, Cathy</style></author><author><style face="normal" font="default" size="100%">Henriques, Manuel O.</style></author><author><style face="normal" font="default" size="100%">Quilhó, Teresa</style></author><author><style face="normal" font="default" size="100%">Čermák, Jan</style></author><author><style face="normal" font="default" size="100%">Chaves, M. Manuela</style></author><author><style face="normal" font="default" size="100%">Pereira, João S.</style></author><author><style face="normal" font="default" size="100%">David, Jorge S.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Root functioning, tree water use and hydraulic redistribution in Quercus suber trees: A modeling approach based on root sap flow</style></title><secondary-title><style face="normal" font="default" size="100%">Forest Ecology and Management</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Drought</style></keyword><keyword><style  face="normal" font="default" size="100%">groundwater</style></keyword><keyword><style  face="normal" font="default" size="100%">soil water</style></keyword><keyword><style  face="normal" font="default" size="100%">Stable isotopes</style></keyword><keyword><style  face="normal" font="default" size="100%">xylem anatomy</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><urls><web-urls><url><style face="normal" font="default" size="100%">http://www.sciencedirect.com/science/article/pii/S0378112713004441</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">307</style></volume><pages><style face="normal" font="default" size="100%">136 - 146</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Mediterranean evergreen oaks have to survive a long summer drought. Roots may play a relevant role under these conditions. We studied their structure and function in a mature Quercus suber L. tree in central Portugal. The root system was mapped till the lowest water table level (4.5 m depth). Xylem anatomy was analyzed in a vertical profile belowground. Sap flow was continuously monitored for 1.5 yrs in the stem and roots of this intensively studied tree (heat field deformation method) and in the stem of four trees (Granier method), in relation to environmental variables and predawn leaf water potential. The sources of water uptake were assessed by stable isotope analyses in summer. Results showed a dimorphic root system with a network of superficial roots linked to sinker roots, and a taproot diverting into tangles of deep fine roots submerged for long periods, with parenchyma aerenchyma. Transpiration was not restricted in summer due to root access to groundwater. The isotopic δ18O signature of twig xylem water was similar to that of groundwater in the dry season. Two functional types of superficial roots were identified: shallow connected and deep connected roots. A modeling approach was built considering that each superficial root was linked to a sinker, with part of the root deep connected (between the stem and the sinker) and part shallow connected (between the sinker and topsoil). This conceptual framework simulated tree stem sap flow from root sap flow with a high efficiency (R2 = 0.85) in four plot trees. On an annual basis, soil water and groundwater contributions were 69.5% and 30.5% of stem flow, respectively. Annual hydraulic lift and hydraulic descent were 0.9% and 37.0% of stem flow, respectively. The trees maximize the exploitation of the environmental resources by using the topsoil water during most of the year, and groundwater together with hydraulic lift (nutrient supply) in the dry summer. This study shows that a dimorphic root system, with roots reaching groundwater, is an efficient strategy of Q. suber trees to cope with seasonal drought. Knowledge of the functional behavior of Q. suber trees under shallow water table conditions may contribute to the definition of better adapted management practices and to anticipate their responses to climate change.</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%">García, Luis V.</style></author><author><style face="normal" font="default" size="100%">Ramo, Cristina</style></author><author><style face="normal" font="default" size="100%">Aponte, Cristina</style></author><author><style face="normal" font="default" size="100%">Moreno, Adela</style></author><author><style face="normal" font="default" size="100%">Domínguez, María T.</style></author><author><style face="normal" font="default" size="100%">Gómez-Aparicio, LORENA</style></author><author><style face="normal" font="default" size="100%">Redondo, Ramón</style></author><author><style face="normal" font="default" size="100%">Marañón, Teodoro</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Protected wading bird species threaten relict centenarian cork oaks in a Mediterranean Biosphere Reserve: A conservation management conflict</style></title><secondary-title><style face="normal" font="default" size="100%">Biological Conservation</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Colonial waterbirds</style></keyword><keyword><style  face="normal" font="default" size="100%">d13C</style></keyword><keyword><style  face="normal" font="default" size="100%">d15N</style></keyword><keyword><style  face="normal" font="default" size="100%">Doñana</style></keyword><keyword><style  face="normal" font="default" size="100%">Heronry</style></keyword><keyword><style  face="normal" font="default" size="100%">Indirect effects</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus suber</style></keyword><keyword><style  face="normal" font="default" size="100%">Stable isotopes</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year><pub-dates><date><style  face="normal" font="default" size="100%">2011///</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">http://linkinghub.elsevier.com/retrieve/pii/S000632071000474X</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">144</style></volume><pages><style face="normal" font="default" size="100%">764 - 771</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Conservation management conﬂicts frequently arise when an overpopulation of a protected organism has negative effects on other valuable elements in the same ecosystem. We studied the interactions between a colony of protected tree-nesting wading birds and a remnant population of centenarian cork oaks that was part of the formerly dominant forests in the Doñana Biological Reserve (SW Spain). A signiﬁcant increase in the tree mortality rates has been recorded in areas that are yearly inﬂuenced by the bird colony. We analysed a cohort of surviving trees using a gradient of nesting bird inﬂuence. Tree-nesting history, bird isotopic signature (d 15 N), tree health-related parameters (defoliation, d 13 C and leaf surface coverage by faeces) and several soil variables were evaluated. Bird inﬂuence was related to increased soil salinity. This increase correlated to increased water-use efﬁciency for the leaves and to crown defoliation, suggesting that the heavily occupied trees are under higher stress and in poorer health condition than the unoccupied ones. We tested structural equations models (SEM) that were based on hypothesised bird effects on the health of the trees. Soil-mediated effects of the nesting birds best explained the symptoms of the declining health of the trees, whereas the percent of leaves’ surface that was covered by faeces did not improve the ﬁtted SEM model. For the reserve’s managers, a challenging trade-off exists between preserving the relict trees, which have a high genetic diversity and a key ecological role in these savannah-like ecosystems, and maintaining the current nesting area for these protected, but expanding, wading birds.</style></abstract><issue><style face="normal" font="default" size="100%">2</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%">Unger, Stephan</style></author><author><style face="normal" font="default" size="100%">Máguas, Cristina</style></author><author><style face="normal" font="default" size="100%">Pereira, João S.</style></author><author><style face="normal" font="default" size="100%">David, Teresa S.</style></author><author><style face="normal" font="default" size="100%">Werner, Christiane</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">The influence of precipitation pulses on soil respiration – Assessing the “Birch effect” by stable carbon isotopes</style></title><secondary-title><style face="normal" font="default" size="100%">Soil Biology and Biochemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Birch effect</style></keyword><keyword><style  face="normal" font="default" size="100%">d13C</style></keyword><keyword><style  face="normal" font="default" size="100%">Irrigation experiment</style></keyword><keyword><style  face="normal" font="default" size="100%">Mediterranean woodland</style></keyword><keyword><style  face="normal" font="default" size="100%">Soil respiration</style></keyword><keyword><style  face="normal" font="default" size="100%">Stable isotopes</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://linkinghub.elsevier.com/retrieve/pii/S0038071710002282</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">42</style></volume><pages><style face="normal" font="default" size="100%">1800 - 1810</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Sudden pulse-like events of rapidly increasing CO2-efﬂux occur in soils under seasonally dry climates in response to rewetting after drought. These occurrences, termed “Birch effect”, can have a marked inﬂuence on the ecosystem carbon balance. Current hypotheses indicate that the “Birch” pulse is caused by rapidly increased respiration and mineralization rates in response to changing moisture conditions but the underlying mechanisms are still unclear. Here, we present data from an experimental ﬁeld study using straight-forward stable isotope methodology to gather new insights into the processes induced by rewetting of dried soils and evaluate current hypotheses for the “Birch“-CO2-pulse. Two irrigation experiments were conducted on bare soil, root-free soil and intact vegetation during May and August 2005 in a semi-arid Mediterranean holm oak forest in southern Portugal. We continuously monitored CO2-ﬂuxes along with their isotopic compositions before, during and after the irrigation. d 13 C signatures of the ﬁrst CO2-efﬂux burst, occurring immediately after rewetting, ﬁt the hypothesis that the “Birch” pulse is caused by the rapid mineralization of either dead microbial biomass or osmoregulatory substances released by soil microorganisms in response to hypo-osmotic stress in order to avoid cell lyses. The response of soil CO2-efﬂux to rewetting was smaller under mild (May) than under severe drought (August) and isotopic compositions indicated a larger contribution of anaplerotic carbon uptake with increasing soil desiccation. Both length and severity of drought periods probably play a key role for the microbial response to the rewetting of soils and thus for ecosystem carbon sequestration.</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><notes><style face="normal" font="default" size="100%">The following values have no corresponding Zotero field:&lt;br/&gt;publisher: Elsevier Ltd</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%">Hemming, Deborah</style></author><author><style face="normal" font="default" size="100%">Yakir, Dan</style></author><author><style face="normal" font="default" size="100%">Ambus, Per</style></author><author><style face="normal" font="default" size="100%">Aurela, Mika</style></author><author><style face="normal" font="default" size="100%">Besson, Cathy</style></author><author><style face="normal" font="default" size="100%">Black, Kevin</style></author><author><style face="normal" font="default" size="100%">Buchmann, Nina</style></author><author><style face="normal" font="default" size="100%">Burlett, Regis</style></author><author><style face="normal" font="default" size="100%">CESCATTI, ALESSANDRO</style></author><author><style face="normal" font="default" size="100%">Clement, Robert</style></author><author><style face="normal" font="default" size="100%">Gross, Patrick</style></author><author><style face="normal" font="default" size="100%">Granier, André</style></author><author><style face="normal" font="default" size="100%">Grünwald, Thomas</style></author><author><style face="normal" font="default" size="100%">Havrankova, Katarina</style></author><author><style face="normal" font="default" size="100%">Janous, Dalibor</style></author><author><style face="normal" font="default" size="100%">Janssens, Ivan A</style></author><author><style face="normal" font="default" size="100%">Knohl, Alexander</style></author><author><style face="normal" font="default" size="100%">Östner, Barbara K</style></author><author><style face="normal" font="default" size="100%">Kowalski, Andrew</style></author><author><style face="normal" font="default" size="100%">Laurila, Tuomas</style></author><author><style face="normal" font="default" size="100%">Mata, Catarina</style></author><author><style face="normal" font="default" size="100%">Marcolla, Barbara</style></author><author><style face="normal" font="default" size="100%">Matteucci, Giorgio</style></author><author><style face="normal" font="default" size="100%">Moncrieff, John</style></author><author><style face="normal" font="default" size="100%">Moors, Eddy J</style></author><author><style face="normal" font="default" size="100%">Osborne, Bruce</style></author><author><style face="normal" font="default" size="100%">Pereira, João Santos</style></author><author><style face="normal" font="default" size="100%">Pihlatie, Mari</style></author><author><style face="normal" font="default" size="100%">Pilegaard, Kim</style></author><author><style face="normal" font="default" size="100%">Ponti, Francesca</style></author><author><style face="normal" font="default" size="100%">Rosova, Zuzana</style></author><author><style face="normal" font="default" size="100%">Rossi, Federica</style></author><author><style face="normal" font="default" size="100%">Scartazza, Andrea</style></author><author><style face="normal" font="default" size="100%">Vesala, Timo</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Pan-European δ13C values of air and organic matter from forest ecosystems</style></title><secondary-title><style face="normal" font="default" size="100%">Global Change Biology</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">carboeuroflux</style></keyword><keyword><style  face="normal" font="default" size="100%">CO2 fluxes</style></keyword><keyword><style  face="normal" font="default" size="100%">ecosystem carbon budget</style></keyword><keyword><style  face="normal" font="default" size="100%">ecosystem respiration</style></keyword><keyword><style  face="normal" font="default" size="100%">isotopic discrimination</style></keyword><keyword><style  face="normal" font="default" size="100%">Stable isotopes</style></keyword><keyword><style  face="normal" font="default" size="100%">δ13C</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2005</style></year></dates><publisher><style face="normal" font="default" size="100%">Blackwell Science Ltd</style></publisher><volume><style face="normal" font="default" size="100%">11</style></volume><pages><style face="normal" font="default" size="100%">1065-1093</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We present carbon stable isotope, δ13C, results from air and organic matter samples collected during 98 individual field campaigns across a network of Carboeuroflux forest sites in 2001 (14 sites) and 2002 (16 sites). Using these data, we tested the hypothesis that δ13C values derived from large-scale atmospheric measurements and models, which are routinely used to partition carbon fluxes between land and ocean, and potentially between respiration and photosynthesis on land, are consistent with directly measured ecosystem-scale δ13C values. In this framework, we also tested the potential of δ13C in canopy air and plant organic matter to record regional-scale ecophysiological patterns. Our network estimates for the mean δ13C of ecosystem respired CO2 and the related ‘discrimination’ of ecosystem respiration, δer and Δer, respectively, were −25.6±1.9‰ and 17.8 ±2.0‰ in 2001 and −26.6±1.5‰ and 19.0±1.6‰ in 2002. The results were in close agreement with δ13C values derived from regional-scale atmospheric measurement programs for 2001, but less so in 2002, which had an unusual precipitation pattern. This suggests that regional-scale atmospheric sampling programs generally capture ecosystem δ13C signals over Europe, but may be limited in capturing some of the interannual variations. In 2001, but less so in 2002, there were discernable longitudinal and seasonal trends in δer. From west to east, across the network, there was a general enrichment in 13C (∼3‰ and ∼1‰ for the 2 years, respectively) consistent with increasing Gorczynski continentality index for warmer and drier conditions. In 2001 only, seasonal 13C enrichment between July and September, followed by depletion in November (from about −26.0‰ to −24.5‰ to −30.0‰), was also observed. In 2001, July and August δer values across the network were significantly related to average daytime vapor pressure deficit (VPD), relative humidity (RH), and, to a lesser degree, air temperature (Ta), but not significantly with monthly average precipitation (Pm). In contrast, in 2002 (a much wetter peak season), δer was significantly related with Ta, but not significantly with VPD and RH. The important role of plant physiological processes on δer in 2001 was emphasized by a relatively rapid turnover (between 1 and 6 days) of assimilated carbon inferred from time-lag analyses of δer vs. meteorological parameters. However, this was not evident in 2002. These analyses also noted corresponding diurnal cycles of δer and meteorological parameters in 2001, indicating a rapid transmission of daytime meteorology, via physiological responses, to the δer signal during this season. Organic matter δ13C results showed progressive 13C enrichment from leaves, through stems and roots to soil organic matter, which may be explained by 13C fractionation during respiration. This enrichment was species dependent and was prominent in angiosperms but not in gymnosperms. δ13C values of organic matter of any of the plant components did not well represent short-term δer values during the seasonal cycle, and could not be used to partition ecosystem respiration into autotrophic and heterotrophic components.</style></abstract></record></records></xml>