Efeitos Diretos e Indiretos dos Gradientes de Elevação e Complexidade da Vegetação sobre Comunidades de Morcegos Phyllostomidae em Ecossistemas de Areias Brancas na Amazônia Central

Abstract

In Tropical ecosystems, topography often serves as a proxy for other environmental variables, and distinguishing the effects of elevation from those of correlated factors is essential for understanding biodiversity patterns. This study investigates the direct and indirect effects of terrain elevation and related variables on the structuring of Phyllostomidae bat assemblages in white-sand ecosystems in Central Amazonia. Our results indicate that species composition differs significantly among the vegetation types campina, non-riparian campinarana and riparian campinarana. Structural equation modeling revealed that vegetation obstruction had the greatest influence on bat diversity, followed by terrain elevation. Frugivorous bats were more prevalent in areas with open vegetation up to 5 meters in height, while animalivorous bats avoided areas with dense vegetation between 5 and 15 meters. Additionally, frugivorous bats were more abundant at lower elevations, whereas animalivorous bats were more common at higher elevations. Notably, the effect of terrain elevation was not mediated by vegetation structure or proximity to streams, suggesting that these factors independently contribute to bat community structuring in white-sand ecosystems.