J Syst Evol ›› 2013, Vol. 51 ›› Issue (1): 71-85.DOI: 10.1111/j.1759-6831.2012.00220.x

• Research Articles • Previous Articles     Next Articles

Phylogenetic beta diversity in tropical forests: Implications for the roles of geographical and environmental distance

1,3Jin‐Long ZHANG 2Nathan G. SWENSON 4Sheng‐Bin CHEN 1Xiao‐Juan LIU 5Zong‐Shan LI 1Ji‐Hong HUANG 1Xiang‐Cheng MI 1Ke‐Ping MA*   

  1. 1(State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China)
    2(Department of Plant Biology, Michigan State University, Michigan 48824, USA)
    3(Graduate University of Chinese Academy of Sciences, Beijing 100049, China)
    4(Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing 210042, China)
    5(State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, Beijing 100085, China)
  • Received:2012-04-10 Published:2012-10-11

Abstract: Various mechanistic theories of community assembly have been proposed ranging from niche-based theory to neutral theory. Analyses of beta diversity in a phylogenetic context could provide an excellent opportunity for testing many of these hypotheses. We analyzed the patterns of phylogenetic beta diversity in tropical tree communities in Panama to test several community assembly hypotheses. In particular, the degree to which the phylogenetic dissimilarity between communities can be explained by geographical or environmental distance can yield support for stochastic or deterministic assembly processes, respectively. Therefore, we examined: (i) the existence of distance decay of phylogenetic similarity among communities and its degree of departure from that expected under a null model; and (ii) the relative importance of geographical versus environmental distance in predicting the phylogenetic dissimilarity of communities. We found evidence that the similarity in the phylogenetic composition of communities decayed with geographical distance and environmental gradients. Null model evidence showed that beta diversity in the study system was phylogenetically non-random. Our results highlighted not only the role of local ecological mechanisms, including environmental filtering and competitive exclusion, but also biogeographical processes such as speciation, dispersal limitation, and niche evolution in structuring phylogenetic turnover. These results also highlight the importance of niche conservatism in structuring species diversity patterns.

Key words: community, distance decay, environmental filtering, neotropical forests, niche conservatism, null model.