Site-specific impacts of a major hurricane on alpha and beta diversity in tropical forest seedling communities

Large scale disturbances are known to impact the alpha and beta diversity of communities. However, whether these disturbances increase or decrease diversity is often debated. The goal of this study was to quantify how the diversity of the seedling community was impacted within and across elevation in the El Yunque forest of Puerto Rico following a major hurricane. We tested two alternative hypotheses, that hurricanes are relatively more homogenizing or non-homogenizing forces, by quantifying changes in alpha and beta diversity of the seedling community post-hurricane. This approach highlights whether ecological mechanisms associated with community homogenization (species-specific survival, successional processes, and reduced environmental heterogeneity) or non-homogenization (resource release, increased environmental heterogeneity, and stochastic processes) structure the seedling community post-hurricane. We compared species richness, Fisher’s α, Simpson’s evenness, and multiple aspects...