The ecological performance of metallophyte plants thriving in geochemical islands is explained by the Inclusive Niche Hypothesis  

作　　者：Helena C.Serrano Cristina Antunes Manuel J.Pinto Cristina Máguas Maria Amélia Martins-Loução Cristina Branquinho 

机构地区：[1]Centro de Biologia Ambiental,Faculdade de Ciências,Universidade de Lisboa,Campo Grande,1749-016 Lisboa,Portugal [2]Jardim Botânico do Museu Nacional de História Natural e da Ciência,Universidade de Lisboa,R.Escola Politécnica 58,1250-102 Lisboa,Portugal

出　　处：《Journal of Plant Ecology》2015年第1期41-50,共10页植物生态学报（英文版）

基　　金：Fundação para a Ciência e Tecnologia(FCT)through project ECODILEMA(POCTI/BIA-BDE/60664/2004 and PPCDT/BIA-BDE/60664/2004);C.B.acknowledges a Investigador FCT contract and H.C.S.acknowledges the PhD grant(SFRH/BD/38289/2007)from FCT。

摘　　要：Aims The Inclusive Niche Hypothesis has not been validated for plants using ecophysiological performance.The few experiments have measured growth and competition but not the physiological response of plants.A metallophyte plant that hyperaccumulates aluminium(Al),Plantago almogravensis,showed a defined spa-tial distribution by occurring mostly on vegetation gaps associ-ated with metalliferous areas(geochemical islands).This case was used to determine,in situ,whether the Inclusive Niche Hypothesis was suitable to explain the extent of the species real-ized niche.Methods The vegetation associated with P.almogravensis geochemical islands in the SW coast of Portugal was mapped.The biotic(neighbouring plants)and abiotic(edaphic)components of the niche were cor-related with parameters of the plant’s ecological and physiological performances(plant density and cover;leaf C and N concentration and isotopic composition;growth).The results were obtained using image analysis,abundance and morphological measures,isotopic signatures and chemical composition.Important Findings The species showed better physiological performance where its ecological performance was lower due to trade-offs with environ-mental constraints.The species’realized niche was mostly limited by shrub competition and soil Al-toxicity.These limits contribute to explain the rarity status of the species:the species has a poor capacity to compete but,due to an enhanced Al-tolerance and Al-hyperaccumulator trait,has the ability to find refuge in geochem-ical islands that are too harsh for most other species.This work,based on ecophysiological field studies,provides support for the Inclusive Niche Hypothesis relating to plant species.

关 键 词：competition ECOPHYSIOLOGY edaphic endemism HYPERACCUMULATION stable isotopes trade-off 

分 类 号：Q94[生物学—植物学]