How does the subtropical landscape configuration influence the ecomorphological traits and community composition of ground-dwelling beetles in southern Brazil?

Ground-dwelling beetles play an important role in ecosystems, linked to soil formation and structuring, fragmentation and transport of organic material, and biological control. Changes in the landscape resulting from habitat fragmentation and changes in land use systems serve as a filter for surface and soil beetle community composition, as the most tolerant species, are able to remain in the environment while others that are less tolerant may disappear. This study aimed to assess the community composition of ground-dwelling beetles and their relationship with environmental variables in fragments of the subtropical landscape in southern Brazil. Hence, evaluations of morphospecies and ecomorphological traits of ground-dwelling beetles in three municipalities were used. In each landscape, a sampling grid was established within a window with 1 km diameter and two sampling periods (autumn and winter) were performed for ground-dwelling beetles, soil attributes, litter, and spatial variables. There was an increase of individuals in the fragments with forest systems and with greater soil cover. The beetle communities of the native forest differed from those of pasture, crop-livestock integration, and no-tillage. The hemiedaphic and epigeous life-forms were associated with eucalyptus plantation and shrub vegetation, respectively. The native forest favored beetles with larger body sizes, compared to pasture, no-tillage, and eucalyptus plantation systems. The functional diversity (FD) and Simpson's indices were similar throughout the landscape. The environmental variables (Macropores, Soil Nitrogen, Aeration Space, Perimeter of the fragments, Litter Dry Weight) showed a relationship with several morphospecies but despite that they explained only a small part of the community structure. The heterogeneity of land use systems in subtropical landscapes was a driver of changes in the composition of ground-dwelling beetle communities and ecomorphological traits. •Studying the diversity of ground-dwelling beetles species in subtropical landscape.•Forests hold larger body sizes of ground-dwelling beetles.•Variation of vegetation cover affects the abundance of the organisms.•The community composition is related with soil, litter, and spatial variables.•The functional diversity of beetles is maintained throughout the landscape.