Ordination diagram based on the canonical correspondence analysis of the taxa abundance data and the best explanatory variables. Abbreviations:  alien species Ch.cur-Ch.curvispinum, C.flu-C.fluminea, D.hae-D.haemobaphes, D.pol-D.polymorpha, D.vill-D.villosus, G.tig-G.tigrinus, H.inv-H.invalida, L.xep-L.xeprovala, P.acu-P.acuta, P.bar-P.barbatus, P.bav-P.bavaricus, P.alb-P.albicola, P.ant-P.antipodarum,  other macroinvertebrate taxa Asel-Asellidea, Baet-Baetidae, Bith-Bithyniidae, Caen-Caenidae, Cera-Ceratopogonidae, Chiro-Chironimidae, Coen-Coenagrionidae, Coro-Corophidae, Dyti-Dytiscidae, Ecno-Ecnomidae, Ench-Enchytraeidae, Erpo-Erpobdellidae, Gloss-Glossiphoniidae, Hali-Haliplidae, Hydr-Hydropsychidae, Lymn-Lymnaeidae, Meso-Mesoveliidae, Naid-Naididae, Psycho-Psychodidae, Simu-Simuliidae, Spha-Sphaeriidae, Veli-Veliidae, Vivi-Viviparidae,  environmental variables Mod-hydromorphologically modified river stretch, Nat-natural river stretch