Understanding plant drought resistance in a Mediterranean coastal sand dune ecosystem:differences between native and exotic invasive species  

作　　者：Cristina Antunes Ana Júlia Pereira Patrícia Fernandes Margarida Ramos Lia Ascensão Otília Correia Cristina Máguas 

机构地区：[1]Centre for Ecology,Evolution and Environmental Changes,Faculdade de Ciências,Universidade de Lisboa,Campo Grande,1749-016 Lisboa,Portugal [2]PPG-Ecologia,Instituto de Biologia,CP 6109,Universidade Estadual de Campinas-UNICAMP,13083-970 Campinas,São Paulo,Brazil [3]SPBotânica-Botanical Society of Portugal,Travessa do Jardim 3,A-dos-Potes,2615-018 Alverca do Ribatejo,Portugal [4]CESAM-Centre for Environmental and Marine Studies,Faculdade de Ciências-CBV,Universidade de Lisboa,1749-016 Lisboa,Portugal

出　　处：《Journal of Plant Ecology》2018年第1期26-38,共13页植物生态学报（英文版）

基　　金：FCT,Portuguese Foundation for Science and Technology(POCTI/BSE/34689/1999);European Union Framework Programme(FP7-PEOPLE-2010-IRSES-269206,INSPECTED.NET project)PhD grant from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior(CAPES;to C.A.).

摘　　要：Aims Mediterranean coastal dunes are habitats of great conservation interest,with a distinctive and rich flora.In the last century,Acacia spp.,native from Australia,have been introduced in Portugal,with the objective of stabilizing sand dunes,and since have become dominant in numerous sand dune habitats.This invasion process led to the reduction of native plant species richness,changed soil characteristics and modified habitat’s microclimatic char-acteristics.The aim of this research was to typify and compare,in Mediterranean sand dune ecosystems,the ecophysiological responses to drought of Helichrysum italicum and Corema album,two native species,and Acacia longifolia,an exotic invasive spe-cies.We addressed the following specific objectives:(i)to com-pare water relations and water use efficiencies,(ii)to evaluate water stress,(iii)to assess water use strategies and water sources used by plants and(iv)to evaluate the morphological adaptations at leaf and phyllode level.Methods In order to obtain an integrative view of ecophysiological patterns,water relations and performance measuring methods have been applied:predawn(ψPD)and midday(ψMD)water potential,chloro-phyll a fluorescence,oxygen isotopic composition of xylem,rain and groundwater(δ18O)and leaf carbon isotopic discrimination(Δ13C).The leaf characteristics of the three species,as well as the histochemistry of non-glandular trichome cell walls,were also studied to identify morpho-traits related to drought resistance.Important Findings The results support our initial hypothesis:although A.longifolia clearly possesses a degree of resistance to water stress,such ability is provided by a different water strategy,when compared to native species.Natives relied on morphological adaptations to restrict water loss,whereas the invasive species adjusted the water uptake as a way to balance their limited ability of restricting water loss.We corroborate that woody native species(i)have a conservative water-saving strategy and minor seasonal variations relative to in

关 键 词：ECOPHYSIOLOGY water use strategy leaf morphology Acacia longifolia Corema album Helichrysum italicum 

分 类 号：Q94[生物学—植物学]