Vegetative Functional Traits,Functional Group Composition Of Common Woody Plants And Their Relationships With Island Spatial Attributes In The Thousand Island Lake,East China

Aims Functional trait is a major index of species and its adaption to evolutionary and ecological events, hence understanding the differences of functional traits among species and functional group composition is beneficial to our understanding of the mechanisms underlying species diversity maintenance.Methods Since interspecific plant functional trait differentiation represents to some extent the niche differentiation, we studied the differentiation of eight functional traits related to water conductance, resource acquisition and utilization in 75 common woody species in the Thousand Island Lake region.Important findings We found the overall interspecific functional trait differentiation was mainly associated with interspecific differentiation in specific leaf area (SLA), chloroplast concentration (Chl) and stomata density (StoD) by principle component analysis (PCA). We found five traits (i.e., chloroplast concentration (Chl), leaf thickness (LT), leaf area (LA), specific leaf area (SLA) and maximum height (MaxH) were constrained by phylogeny (i.e., P<0.05 for Blomberg’s K) to some extent. We found a great number of significant pairwise trait correlations, and after PIC adjustment, these significant correlations mostly remained, while some correlations changed in significance level or direction. We also found the single trait and the principle component 1 (PC1) and principle component 2 (PC2) values of all traits were not related to species abundance. Species were divided into three groups, including thin-leaf group, thick-leaf group and high-density leaf group. Tukey test showed that different functional group’s functional traits such as SLA, ChL had significant differences, however, LA and StoD of them had no difference. The proportion of species abundance of every functional group on the 29 islands was different. Island spatial attributes (size and isolation) had no significant influence on the proportion of abundance of every functional group on the islands by linear model analysis, and they had no significant effect on species functional traits of the communities at island level. This study suggests the functional trait differentiation of woody species in the fragmented successional Masson pine forest of the Thousand Island Lake region is constrained by both phylogeny and evolutionary history; and differentiate on major environmental resource axes (i.e., irradiance and water); but they may not relate to species abundance in the fragmented forests at early successional stage. In addition, island spatial attributes have no significant effect on functional group abundance and species functional traits of the communities.