Habitat type strongly influences the structural benthic invertebrate community composition in a landscape characterized by ubiquitous, long-term occurrences of agricultural stress

The importance of small water bodies for biodiversity and ecosystem processes has long been neglected in research and policy development. However, due to their heterogeneous characteristics and habitat structures, these water bodies are biodiversity hotspots for various aquatic and terrestrial organisms. This was already shown for example for rotifers, aquatic birds, and amphibians. Knowledge of benthic invertebrate community structures in small water bodies is scarce. Thus, we performed a comprehensive field study of these structures in an agricultural landscape in the northeastern German lowlands. We obtained a dataset containing biological (taxon abundances) and chemical (pesticide residue and nutrient concentrations) data, as well as data on environmental parameters (e.g., conductivity and habitat type) for 111 samples. The dataset was analysed by using generalized linear models, permutational multivariate analysis of variance, and partial redundancy analysis to understand the relationships among benthic invertebrate communities, agricultural stressors, and environmental parameters. The factor that best explained structural community compositions was the habitat type. Pesticides and nutrient concentrations are of minor importance in our analysis. Most likely due to the ubiquitous and long-term occurrence of the agricultural stressors, the structural indices used in benthic invertebrate biomonitoring were not sufficiently sensitive.