Carabid beetle (Coleoptera: Carabidae) distribution in a rural landscape based on habitat diversity and habitat characteristics

The spatial arrangement of ecosystems in an ecological landscape is assumed to be of importance with respect to species diversity. In order to improve current knowledge with respect to this aspect, carabid beetles were studied in six study sites, representing differently treated agricultural and post-agricultural areas and their surrounding habitats, over the period 2013-2015. Additionally, phytosociological surveys were elaborated on the study sites, in order to elaborate indicator values for selected environmental characteristics. We wanted to study (1) the similarities between the study sites and their contribution to overall species diversity, (2) the constancy of similarities between the study sites over several years, and (3) influence of environmental factors on the distribution of the species. Altogether, 1402 individuals belonging to 65 species were collected. Numbers of species differed strongly on the individual study sites in single years, but taking into account all three years the differences were much less significant. The number of exclusive species on the individual study sites ranged from 3 to 11 species, with the highest number on an agricultural field. Cluster analysis and correspondence analysis (CA) showed that the samples of the study sites from the different years were generally similar to each other. The distribution of the study sites along the ordination axis indicated a high importance of stages of succession (management intensity) followed by moisture conditions. The analysis of the indicator values, however, indicated light, acidity and humus content as most important. The study confirmed the assumption that a diversified landscape contributes to species diversity. In this context anthropogenic ecosystems should be taken into account.