Influence of environmental factors on macrozoobenthos formation in water bodies of lowland zone of the Nakhchivan Autonomous Republic

Ecological features of macrozoobenthos of the Nakhchivanchai River, Negram and Uzunoba water reservoirs, springs and other flowing water bodies in the lowland zone (700-1200 m over sea level) of the Nakhchivan Autonomous Republic were studied. 115 species of macrobenthic bottom organisms belonging to 15 systematic groups were found in the bottom fauna of aquatic ecosystems. For the first time one family (Phryganeidae), one genus (Phryganea) and 12 species of organisms are indicated for the fauna of the autonomous republic. It was revealed that larvae of water-air rheophilic organisms form the basis of macrozoobenthos of the lower reaches of the Nakhchivanchai River, starting from the dam of H. Aliyev reservoir to the river mouth (69 species), and springs and other flowing water bodies (79 species). As a result of simplification of biocenoses of Uzunobi and Negram reservoirs under conditions of special hydrological regime of water bodies located in southern zones, the fauna diversity index (32 species in total) is low. 14 species of macrozoobenthos were dominant due to their wide ecological plasticity, frequency of occurrence, abundance and biomass.