Spatial variability of edaphic attributes on Coleoptera (Insecta) in land use systems

Abstract

The alteration of the natural landscape structure affects abiotic conditions and promotes a biological response in the local community. The diversity of edaphic organisms is related to the diversity of other taxa and abiotic characteristics, which represent potential bioindicators of the ecosystem. The objective of this study was to identify which soil attributes explain the beetle community and explore their effects through spatial modeling. The study was conducted in three landscapes in western Santa Catarina (Brazil), located in Chapecó, Pinhalzinho, and São Miguel do Oeste. The land use and cover systems identified were: no-till farming, native forest, pasture, eucalyptus planting, crop-livestock integration, and shrub vegetation. Soil, plant litter, and Coleoptera samples were collected. The variables were selected through the Threshold Indicator Taxa Analysis and spatial modeling by Geostatistics. Higher values of soil penetration resistance, associated with the no-till system, resulted in a lower abundance of Staphylinidae beetles, conditioned by total soil porosity. Lower volumetric moisture values, identified in the no-till system near native vegetation fragments, led to increased abundance of Nitidulidae family beetles, due to the family's adaptability to dry environments. The trend of higher microbial carbon concentration in native vegetation areas explained the greater abundance of Chrysomelidae family beetles in these areas, due to the phytophagous habits of the species in this family. Thus, the Coleoptera community has the potential to serve as bioindicators of soil quality, and their relationships with soil physics, chemical, and microbial attributes can be spatially modeled through Geostatistics.