Isolated alpine habitats reveal disparate ecological drivers of taxonomic and functional beta-diversity of small mammal assemblages  

作　　者：Wen-Yu Song Xue-You Li Zhong-Zheng Chen Quan Li Kenneth Otieno Onditi Shui-Wang He Xue-Long Jiang 

机构地区：[1]State Key Laboratory of Genetic Resources and Evolution,Kunming Institute of Zoology,Chinese Academy of Sciences,Kunming,Yunnan 650223 China [2]Kunming College of Life Science,University of Chinese Academy of Sciences,Kunming,Yunnan 650223 China [3]Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education,School of Ecology and Environment,Anhui Normal University,Wuhu,Anhui 241000 China

出　　处：《Zoological Research》2020年第6期670-683,共14页动物学研究（英文）

基　　金：supported by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP,2019QZKK0501);National Key Research and Development Program of China(2017YFC0505202);National Natural Science Foundation of China(31601874);National Natural Science Foundation of China(31702007);Biodiversity Survey,Monitoring,andAssessment Program(2019HB2096001006)。

摘　　要：The interpretation of patterns of biodiversity requires the disentanglement of geographical and environmental variables.Disjunct alpine communities are geographically isolated from one another but experience similar environmental impacts.Isolated homogenous habitats may promote speciation but constrain functional trait variation.In this study,we examined the hypothesis that dispersal limitation promotes taxonomic divergence,whereas habitat similarity in alpine mountains leads to functional convergence.We performed standardized field investigation to sample non-volant small mammals from 18 prominent alpine sites in the Three Parallel Rivers area.We estimated indices quantifying taxonomic and functional alpha-and beta-diversity,as well as beta-diversity components.We then assessed the respective importance of geographical and environmental predictors in explaining taxonomic and functional compositions.No evidence was found to show that species were more functionally similar than expected in local assemblages.However,the taxonomic turnover components were higher than functional ones(0.471±0.230 vs.0.243±0.215),with nestedness components showing the opposite pattern(0.063±0.054 vs.0.269±0.225).This indicated that differences in taxonomic compositions between sites occurred from replacement of functionally similar species.Geographical barriers were the key factor influencing both taxonomic total dissimilarity and turnover components,whereas functional betadiversity was primarily explained by climatic factors such as minimum temperature of the coldest month.Our findings provide empirical evidence that taxonomic and functional diversity patterns can be independently driven by different ecological processes.Our results point to the importance of clarifying different components of beta-diversity to understand the underlying mechanisms of community assembly.These results also shed light on the assembly rules and ecological processes of terrestrial mammal communities in extreme environments.

关 键 词：Beta-diversity partitioning Community assembly Environmentalstress Habitat homogeneity Hengduan Mountains River barriers Sky islands Tree line 

分 类 号：Q958[生物学—动物学]