Unveiling Rainfall's Role in Shaping Woody Plant Functional Traits and Diversity in Northern Namibia

Abstract

Changes in precipitation patterns affect tree populations by altering their functional traits, yet functional diversity is often underestimated in ecological studies. This study analysed changes in plant species diversity and functional traits along an increasing rainfall gradient, using systematic sampling at 13 points along a 1200-km transect. Plant species diversity fluctuated with no apparent significant effect that could be attributed to increasing rainfall gradient, yet species diversity was significantly highest at sites with high rainfall. While there was no apparent statistical difference in the Simpson Diversity Index among sites, beta diversity was high among all sites. Functional traits varied along the gradient, with functional richness significantly affected by annual average rainfall. The study underscores the importance of both plant species and functional diversity in ecosystems and suggests future research should include more functional traits and sufficient data collection to further elucidate the complex interactions between tree populations, functional traits and precipitation patterns.