Invertebrate fauna of the Minina River, taking into account environmental factors

A total of 5,613 macroinvertebrate specimens, belonging to 43 taxa of varying systematic positions, were collected at four study sites in the Minina River. Dominant in the material collected were Gammarus sp. (33.9%), Chironomidae larvae (30.4%) and Ephemera sp. larvae (7.0%). More individuals (3,551) and taxa (39) were caught in the lentic zone than in the lotic zone (2,062 specimens and 30 taxa). The biological diversity index ranged from 1.57 to 3.14 within the sites and from 1.04 to 3.77 within habitats (zones of the river). The taxonomic composition and the abundance of the fauna were mainly in fluenced by biotic factors (e.g. amount of aquatic vegetation) and abiotic factors (e.g. water current and type of bottom sediment), while human impact (presence of hydraulic structures, straightening of the river bed) did not significantly affect the fauna.