Response of beetle communities to the heterogeneity of vegetation in high altitude habitats in north-western Argentina

Abstract

The dynamics and complexity of plant communities influence the diversity and distribution of animals in various environments. Coleoptera are the most diverse group of insects and are valued as monitoring and environmental assessment tools. However, their diversity and dynamics in these high-altitude environments are poorly known. Using pitfall traps and suction sampling, we collected beetles to study their community responses to changes in different vegetation heterogeneities (low, intermediate, and high). The heterogeneity gradient was determined by considering the dominant plant species in each habitat, the percentage of vegetation coverage, and the percentage of vertical strata. Guild's responses to vegetation heterogeneity were analysed in conjunction with the patterns of alpha and beta diversity in beetles. Representatives of 41 species/morphospecies of beetles, 16 families, and four guilds were reported. Significant variations were observed in guild composition and alpha and beta diversity, especially between high and low vegetation heterogeneity habitats. The significant species turnover between sites is the main factor responsible for the high beta diversity, supporting considerable habitat heterogeneity within these environments. Phytophagous, detritivorous, necrophagous, and predatory beetles exhibited distinct responses to the vegetation's heterogeneity. This suggests that every habitat under investigation possesses a distinct structure of beetle communities. Predators were important in habitats with more diverse vegetation, while phytophagous were important in the most homogeneous ones. Beetle communities in the Puna and Altos Andes of Salta province respond positively to vegetation heterogeneity, which plays a crucial role in determining the composition of small-scale beetle communities in arid high-altitude environments.