<?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%">Mereu, Simone</style></author><author><style face="normal" font="default" size="100%">Gerosa, Giacomo</style></author><author><style face="normal" font="default" size="100%">Marzuoli, Riccardo</style></author><author><style face="normal" font="default" size="100%">Fusaro, Lina</style></author><author><style face="normal" font="default" size="100%">Salvatori, Elisabetta</style></author><author><style face="normal" font="default" size="100%">Finco, Angelo</style></author><author><style face="normal" font="default" size="100%">Spano, Donatella</style></author><author><style face="normal" font="default" size="100%">Manes, Fausto</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Gas exchange and JIP-test parameters of two Mediterranean maquis species are affected by sea spray and ozone interaction</style></title><secondary-title><style face="normal" font="default" size="100%">Environmental and Experimental Botany</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Antagonistic interaction</style></keyword><keyword><style  face="normal" font="default" size="100%">dark respiration</style></keyword><keyword><style  face="normal" font="default" size="100%">JIP-test</style></keyword><keyword><style  face="normal" font="default" size="100%">OTC</style></keyword><keyword><style  face="normal" font="default" size="100%">Oxidative stress</style></keyword><keyword><style  face="normal" font="default" size="100%">PSI</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2011</style></year></dates><publisher><style face="normal" font="default" size="100%">Elsevier B.V.</style></publisher><volume><style face="normal" font="default" size="100%">73</style></volume><pages><style face="normal" font="default" size="100%">80-88</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">Mediterranean maquis coastal ecosystems are subject to multiple oxidative stresses of both natural and anthropic origin, as sea spray, drought, high irradiance and ozone. In this article it is hypothesized that the interaction of ozone and sea spray is additive as a consequence of a higher reactive oxigen species accumulation. To test the hypothesis, an experiment was conducted in an Open Top Chambers facility where plants of Quercus ilex L. and Arbutus unedo L. were exposed to two levels of ozone and two levels of sea spray. The response of the species was evaluated by measurements of structural parameters (shoot growth and leaf biomass) and physiological parameters (leaf level gas exchange and chlorophyll a ﬂuorescence). The results contradict the hypothesis as the interaction of the two stresses is antagonistic on both species. The structure of both species was negatively affected by sea spray, however the two stresses combined allowed a higher growth and leaf area in A. unedo. The leaf level physiology of A. unedo was only moderately affected by the two stresses alone and in combined, while that of Q. ilex was altered to a further extent by sea spray and by its combination with ozone: photosynthesis and efﬁciency of the PSII was reduced by sea spray while the ratio of PSII to PSI was increased; the two stresses combined, instead, decreased the PSII to PSI ratio allowing for a higher photosynthesis. It is concluded that A. unedo is more resistant than Q. ilex to the two stresses alone and in combination, that ozone and sea spray interact antagonistically, and that the activity of PSI has a key role in the stress response</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%">Hymus, Graham J</style></author><author><style face="normal" font="default" size="100%">MASEYK, KADMIEL</style></author><author><style face="normal" font="default" size="100%">Valentini, Riccardo</style></author><author><style face="normal" font="default" size="100%">Yakir, Dan</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Large daily variation in 13C-enrichment of leaf-respired CO2 in two Quercus forest canopies</style></title><secondary-title><style face="normal" font="default" size="100%">New Phytologist</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">carbon isotope ratio</style></keyword><keyword><style  face="normal" font="default" size="100%">dark respiration</style></keyword><keyword><style  face="normal" font="default" size="100%">forest canopies</style></keyword><keyword><style  face="normal" font="default" size="100%">fractionation</style></keyword><keyword><style  face="normal" font="default" size="100%">Quercus spp</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%">167</style></volume><pages><style face="normal" font="default" size="100%">377-384</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">* • The use of the 13C : 12C isotopic ratio (δ13C) of leaf-respired CO2 to trace carbon fluxes in plants and ecosystems is limited by little information on temporal variations in δ13C of leaf dark-respired CO2 (δ13Cr) under field conditions. * • Here, we explored variability in δ13Cr and its relationship to key respiratory substrates from collections of leaf dark-respired CO2, carbohydrate extractions and gas exchange measurements over 24-h periods in two Quercus canopies. * • Throughout both canopies, δ13Cr became progressively 13C-enriched during the photoperiod, by up to 7, then 13C-depleted at night relative to the photoperiod. This cycle could not be reconciled with δ13C of soluble sugars (δ13Css), starch (δ13Cst), lipids (δ13Cl), cellulose (δ13Cc) or with calculated photosynthetic discrimination (Δ). However, photoperiod progressive enrichment in δ13Cr was correlated with cumulative carbon assimilation (r2 = 0.91). * • We concluded that there is considerable short-term variation in δ13Cr in forest canopies, that it is consistent with current hypotheses for 13C fractionation during leaf respiration, that leaf carbohydrates cannot be used as surrogates for δ13Cr, and that diel changes in leaf carbohydrate status could be used to predict changes in δ13Cr empirically.</style></abstract></record></records></xml>