Traits uncover quasi-neutral community assembly in a coastal heath vegetation  

作　　者：JoséLuiz Alves Silva Alexandre Fadigas Souza Louis Stephen Santiago 

机构地区：[1]Programa de Pós-Graduação em Ecologia,Departamento de Ecologia,Universidade Federal do Rio Grande do Norte,Natal 59078-970,Brazil [2]Departamento de Ecologia,Universidade Federal do Rio Grande do Norte,Natal 59078-970,Brazil [3]Department of Botany and Plant Sciences,University of California,2150 Batchelor Hall,Riverside,CA 92521,USA [4]Smithsonian Tropical Research Institute,Balboa,Ancón,Panamá,Republic of Panamá

出　　处：《Journal of Plant Ecology》2019年第4期703-712,共10页植物生态学报（英文版）

摘　　要：Aims Trait-based approaches are increasingly being used in ecology due to their potential to explain and predict community structure and dynamic regardless of species identities.Here,we asked whether coastal heath vegetation established in stressful habitats could be assembled by quasi-neutral mechanisms based on functional trait distribution.Communities are organized through quasi-neutral dynamics if abiotic gradients and/or species interactions impose sorting on functional traits and species performances,but not on species phylogenetic relatedness and occurrence.Methods The study was conducted in a coastal area containing tall dunes near the sea,and relatively flat areas punctuated by short palaeodunes further inland,Northeastern South America.We evaluated 10 traits of the 21 most abundant species,as well as eight abiotic variables in 70 plots(25 m^(2))established in dune tops,valleys,flat and steep microenvironments.The effect of environmental filter was tested by linear mixed models(LMM)between each community-weighted mean(CWM)trait and the abiotic variables,and by two indices of environmental filtering based on intra-and interspecific-trait vari-ability relative to null models.To evaluate the effect of species inter-actions,we used an index of niche overlap relative to null models,and LMMs between this index and the species richness of plots.Important Findings The environmental filtering index did not deviate from null expect-ations for any trait.Models that included individual variability per-formed similarly to models that used species mean traits.However,the explicit consideration of environmental gradients by CWM ana-lyses revealed functional patterns that would remain undetected if trait distribution was analyzed only.In addition,intraspecific vari-ation in the stem length was an important driver of species diversity as suggested by the relationship between species richness and the niche overlap index.Based on the occurrence and phylogenetic re-latedness of species,previous work in the same system found

关 键 词：RESTINGA heath vegetation harsh environment stress-tolerant species response traits 

分 类 号：Q94[生物学—植物学]