While using phylogenetic and functional approaches to test the mechanisms of community assembly, functional traits often act as the proxy of niches. However, there is little detailed knowledge regarding the correlation between functional traits of tree species and their niches in local communities.

Prof. CAO Min and his team of Xishuangbanna Tropical Botanical Garden (XTBG) conducted a study in the 20-ha Xishuangbanna Forest Dynamics Plot (FDP) (21°36′N, 101°34′E) and the 6-ha Ailaoshan FDP (24°32′N, 102°01′E) in tropical and subtropical China, respectively. They integrated functional trait data, well-resolved molecular phylogenies and topographical data from the two plots to test whether there were explicit linkages between traits, niches, phylogenetic relatedness and community phylogenetic and functional trait dispersion patterns.

They asked: 1) was there a significant relationship between traits and environmental niches? 2) Whether the traits linked to topographical niches had phylogenetic signal; 3) whether they could formulate an explicit linkage between traits and niches, the evolutionary history of traits and the phylogenetic and functional dispersion of tree communities in the two forest dynamics plots along local-scale topological gradients.

They found that functional traits co-varied with environmental niches at the species level in both of the FDPs, supporting that functional traits can be used as a proxy for local-scale environmental niches. Functional traits showed significant phylogenetic signals in both of the FDPs. The phylogenetic and functional dispersion were significantly clustered along topographical gradients in the Ailaoshan FDP but overdispersion in the Xishuangbanna FDP.

The study entitled “Functional traits of tree species with phylogenetic signal co-vary with environmental niches in two large forest dynamics plots” has been published in Journal of Plant Ecology.

20-ha Xishuangbanna FDP and 6-ha Ailaoshan FDP (Image by Mo Xiaoxue)