Patch isolation and shape predict plant functional diversity in a naturally fragmented forest

Aims It is known that taxonomic diversity can be predicted by the spatial configuration of the habitat,in particular by its area and degree of iso-lation.However,taxonomic diversity is a poor predictor of ecosystem functioning.While functional diversity is strongly linked to the func-tionality and stability of ecosystems,little is known about how changes in the spatial configuration of the habitat affect functional diversity.In this study,we evaluated whether the spatial configuration of forest patches predicts the functional diversity of plants in a fragmented forest.Methods Five functional leaf traits(leaf dry matter content,leaf punch force,specific leaf area,leaf size and leaf thickness)were measured for 23 dominant plant species in 20 forest patches in a naturally fragmented forest on the yucatan Peninsula.Abundance-weighted multivariate and individual trait metrics of functional diversity were calculated and cor-related with size,degree of isolation and the shape of forest patches.Important Findings Patch shape was negatively correlated with multivariate and individ-ual trait(leaf dry matter content and leaf size)metrics of functional diversity.Patch isolation measures were also negatively correlated with individual trait(leaf dry matter content,leaf punch force and leaf size)metrics of functional diversity.In other words,greater patch shape irregularity and isolation degree impoverish plant func-tional variability.This is the first report of the negative effects of patch shape irregularity and isolation on the functional diversity of plant communities in a forest that has been fragmented for a long time.