Аннотация
Changes in hydrological conditions in the Aral-Syr Darya Basin have been particularly pronounced over the past ten years. The relevance of studying the influence of environmental factors on aquatic fauna is evident today and requires identifying the causes of adverse changes, as well as taking precautionary measures. The study focuses on the Shardara Reservoir, a major reservoir located on the Syr Darya River in southern Kazakhstan. The article presents the results of research conducted in 2020–2024, including an analysis of the biological indicators of commercial fish species in the Shardara Reservoir and an assessment of both abiotic and biotic influencing factors. Based on data obtained from the Kazhydromet website for the Turkistan Region, annual water discharge rates were calculated. The water-level conditions of the reservoir were also assessed using modern geographic information system (GIS) technologies.