STATE OF THE ZOOPLANKTON COMMUNITY OF WATER COURSES OF THE VOLGA RIVER DELTA IN A SEASONAL ASPECT
Kraynova Anastasia Valeryevna - Senior Lecturer, Department of Ecology, Nature Management, Land Management, and Life Safety, Astrakhan State University named by V.N. Tatishchev, Russia, 414056, Astrakhan, Tatishchev st., 20a, nasty_dubovski@bk.ru
Nasibulina Botagoz Murasovna - Doctor of Biological Sciences, Associate Professor, Acting Head of the Department of Ecology, Nature Management, Land Management and Life Safety, Astrakhan State University named by V.N. Tatischev, Russian Federation, 414056, Astrakhan, Tatishchev st., 20a, aspu.nasibulina@yandex.ru
Urazgalieva Rashida Ainurovna - Leading Ichthyologist, Caspian Branch of the Federal State Budgetary Educational Institution "Glavrybvod", Russia, 414052, Astrakhan, Yablochkov st., 38A,
The zooplankton community structure was analyzed as a significant indicator of the state of freshwater ecosystems. The study area is administratively located within the boundaries of the Astrakhan Region on the water bodies of the Volga Delta—the Volga River, Bakhtemir and Kizan branches. Observations were conducted during the 2024 growing season. The following were dominant in terms of quantitative indicators: in terms of abundance - rotifers, represented mainly by Brachionus calyciflorus; in terms of biomass - copepods, mostly repre-sented by the Cyclopidae family. In addition to rotifers and copepods, cladocerans were noted in the studied hydrobiological samples; the following representatives were dominant in terms of quantitative indicators: Chidorus sphaericus, Bosmina longispina, and Daphnia cucullata. The weighted average saprobity indicators were calculated. It has been established that all watercourses considered within the framework of these studies belong to the ? -mesasample zone, and accordingly, it is possible to classify them as moderately polluted water bodies, which confirms the need for regular observations in the area under consideration, in view of the increasing pressure of anthropogenic factors and the importance of preserving the unique nature of the Volga River delta.
Key words: zooplankton, Volga River, Bakhtemir and Kizan Rivers, indicator organisms, hydrobiological monitoring, assessment of surface water quality
