Diversity of carabid beetle assemblages (Coleoptera: Carabidae) in a post-industrial slag deposition area

In order to determine the effect of environmental degradation on species diversity and to determine the state and rate of recolonization of post-industrial areas, four types of research plots were set up on the Skawina Power Plant slag heap and on adjacent reference areas in a gradient of succession (the early-successional top of the slag heap and its late-successional rehabilitated embankments). A total of about 2,000 individuals belonging to 47 species of the carabid family were collected. Nonmetric multidimensional scaling indicated substantial differentiation of the composition and structure of the assemblages of the slag heap and reference areas (stress = 0.1). Every type of assemblage on the slag heap differed statistically significantly from the reference assemblages in terms of the Bray-Curtis similarity index (ANOSIM, p<0.01), both in the environmental degradation gradient and the succession gradient. A generalized linear model (GLM) showed that the severe transformation of the area and the unfavourable soil conditions statistically significantly differentiate parameters of carabid species diversity and richness, causing them to decrease irrespective of the stage of succession and land rehabilitation. This indicates a considerable delay in successional processes over the entire area studied, as well as the early-successional character of the carabid assemblages present there, which persists despite rehabilitation.