Linear and nonlinear effects of nutrient enrichments on the diversity of macrobenthos in lowland watercourses

Abstract The study concerns the relationships between taxonomic, functional and phylogenetic diversity of benthic invertebrates inhabiting watercourses abiotic parameters associated with excessive nutrients load (concentration Kjejdahl nitrogen, nitrates, phosphorus, organic carbon dissolved oxygen, values BOD5 electrolytic conductivity). research used data on species composition leeches, molluscs larval forms odonates chironomid dipterans. Their description using mathematical functions allowed to determine whether reaches maximal at extreme or moderate enrichment. In most cases, statistically significant were unimodal—the highest was observed intermediate content parameters, however different patterns relationships, monotonic inverse quadratic, also observed. Indirect impacts enrichment found as relationships. Significant responses clearer stronger than taxonomic diversity. identification fauna level for obtaining precise results that could enable selection appropriate effective assessment environmental degradation.