Geographic distance and environmental variation drive community structure of woody plants in Neotropical seasonally dry forest fragments in the Colombian Caribbean

Background Montes de Maria is the best-preserved tropical dry forest fragment in the Colombian Caribbean, making it a good model to relate environmental and geographic factors to woody plant community structure. Aims We related alpha and beta diversity of woody plant communities to geographic distance and bioclimatic factors to understand the underlying factors of community structure. Methods We compared species composition among seven sites and calculated alpha (using effective numbers of species) and beta diversity using Whitaker and Bray-Curtis dissimilarity index. Canonical correspondence analysis (CCA) and a Mantel test were used to quantify how community structure was related to environmental and/or geographic distance. Results We found that Montes de Maria is as diverse as other dry forest fragments in Colombia. We detected three groups of communities which were shaped mainly by turnover associated with both precipitation and geographic distance. Conclusions The high beta diversity of the dry forest of Montes de Maria is related to a mixture of environmental variation and geographic distance.