Functional diversity and species diversity in flooded and unflooded tropical forests

Abstract

Functional diversity and species diversity provide information to understand differences between plant communities from a contrasting environment and the complementary on regional scale. Environmental variation determines which plants can persist in the community via species sorting processes; forest exposed to extended inundation each year has shown divergence in plant community composition, structure, and functional diversity, compared with unflooded dense forest. Here, we researched flooded and unflooded forests in the upper Magdalena River Valley (Colombia) to quantify and compare the plant species diversity and plant functional diversity. We calculated three components of functional diversity (i.e., functional richness, functional evenness, and functional divergence), we also used a measure of functional richness weighted by species abundance. Our results show that the plant community in the unflooded forest has higher stem density and lower basal area than flooded forests. Also, we show that tree communities in the flooded forests had higher specific leaf area, but lower wood density, suggesting an acquisitive resource strategy. Species diversity and functional diversity were higher in the plant community from the unflooded forest. Our findings of the functional traits and the functional diversity components reinforce the idea that the variation between flooded and unflooded forests is going beyond the species list in the plant communities. However, it is still unclear whether any general patterns exist regarding differences between flooded and unflooded tropical forests.