关键词: 群落生态学, 系统进化树, 尺度, 功能性状

Abstract

Community assembly has long been an important issue in community ecology. The study of community phylogenetic structure, which applies phylogeny to community ecology studies, has provided an effective way to disentangle the most important ecological processes that drive community assembly. Studying the phylogenetic structure of a community involves firstly the construction of a supertree representing the species pool of the community, then a calculation of phylogenetic distances between all species within the community, and finally an inference of phylogenetic structure (e.g., clustering, overdispersion) obtained by statistically testing whether the obtained phylogenetic distances are different from those expected under random model, hence revealing key ecological processes involved in community assembly (e.g., habitat filtering, competition exclusion). Community phylogenetic structure is different when studied at different taxonomic, spatial or temporal scales. At small spatial scales, community phylogenetic pattern tends to change from clustering to overdispersion with decreasing taxonomical scale or increasing tree age class, while the pattern tends to be tighter clustering at larger spatial scales. Phylogenetic information also indicates the influence of environmental factors and studying community phylogeny at the metacommunity level helps to understand regional ecological processes. In addition, phylogenetic structure can help to explore neutral theory, density-dependent hypothesis and other theories in ecology, and even to predict community dynamics and evolution under disturbance. The future application of phylogenetic structure to disclosing underlying causes of community assembly demands the joint analysis of ecological traits and environment factors and, the consideration of both local processes (e.g., microenviroment, biological interactions) and regional processes (e.g., geological history, speciation). In terms of methodological aspects, to construct a phylogenetic tree, appropriate gene segments should be used and the tree needs to be corrected using ecological traits in order to reflect more exact phylogenetic distances among species. Furthermore, more effective statistical models and indices are needed to increase statistical power.

Key words: community ecology, phylogenetic tree, scales, functional traits