Beyond forested habitats in tropical ecosystems: the influence of landscape structure for dung beetle assemblages from open habitats
摘要
Native open habitats in tropical ecosystems are often overlooked despite their ecological importance and unique community structure. Understanding how landscape composition and configuration influence biodiversity in these environments is essential for conservation planning.
ObjectivesWe evaluated how landscape structure—specifically landscape composition (forest cover, open vegetation) and configuration (edge density, patch number, landscape diversity, NDVI)—affects dung beetle assemblages in natural open-canopy habitats of the Cerrado. We examined responses at both community and functional-group levels.
MethodsDung beetles were sampled using baited pitfall traps across 15 open-canopy sites along a gradient of landscape structure. Species richness, abundance, assemblage composition, functional (e.g., tunnellers and rollers) and trophic (e.g., generalists and coprophagous) groups were analyzed with generalized linear models and redundancy analysis. Landscape metrics were extracted at four spatial scales (100–400 m radius), and the best-fitting scale was selected for each variable.
ResultsWe collected 1,382 individuals from 27 species. Edge density emerged as the most influential configuration metric, negatively affecting overall abundance and reducing tunneller species richness and abundance. Forest cover increased the abundance of diet-generalist species. Neither landscape diversity nor NDVI significantly predicted richness or abundance, although NDVI explained species turnover at the 300-m scale.
ConclusionsLandscape configuration, particularly edge density, is a key driver of dung beetle diversity in open-canopy habitats, reducing both taxonomic and functional components of assemblages. Conserving large, less fragmented open habitats and minimizing edge creation are crucial for maintaining dung beetle diversity and ecosystem functioning in the Cerrado.