Distribution of macrozoobenthos of flowing water bodies by altitudinal belts of the Nakhchivan Autonomous Republic

Spatial distribution, species structure and ecological indicators of macrozoobenthos of flowing water bodies by altitude belts of Nakhchivan Autonomous Republic were studied. Macrobenthos fauna of the rivers of the region is formed in psammoreophilic, phytoreophilic and peloreophilic biocenoses with a great advantage of lithoreophilic biocenosis. The lithoreophilic biocenosis of rivers of the mountain and high-mountain belts is characterized by extensive area and abundance of species diversity. The core of the lithoreophilic biocenosis is composed of populations of rheophilic organisms such as moths, mayflies, vernal pools and simulids; its usual inhabitants are also rheophilic larvae of chironomids of the genus Polypedilum , Endochironomus , Eukiefferiella , Cricotopus and Orthocladius . The family composition of the fauna was found to be relatively stable along the rivers. Differences in the species composition of macrobenthos fauna, change of dominant species in biocenoses are related to biological features of the main species, anthropic and anthropogenic impacts, as well as different time of research. The species composition of macrozoobenthos of the rivers of the autonomous republic decreases from the source to the mouth.