Tree communities and functional traits determine herbivore compositional turnover

Abstract

There are many factors known to drive species turnover although the mechanisms by which these operate are less clear. Based on comprehensive datasets we used zeta diversity and multi-site generalized dissimilarity modelling to investigate the pattern and determinants of species turnover for Lepidoptera herbivores. We found that the average number of shared herbivore species declined sharply with an increasing number of plots, with complete changes in caterpillar species composition observed even at ne spatial scales. Plant community characteristics rather than abiotic factors were found to play key roles in driving caterpillar compositional turnover, although these effects varied with increasing plots due to the varying contributions of rare and common species to compositional turnover. Our study reveals details of the impact of phylogeny-and trait-mediated processes of trees on herbivore compositional turnover, which has implications for forest management and conservation and potential avenues for maintenance of heterogeneity in herbivore communities.