TAXONOMIC COMPOSITION AND QUANTITATIVE INDICATORS OF BENTHIC INVERTEBRATES IN LAKE KOLOVERTNOE

Abstract

Abstract. The article presents the study of the species composition and quantitative characteristics of benthic invertebrates in Lake Kolovertnoye during 2024–2025. A total of 14 taxa were recorded in the lake, including oligochaetes, crustaceans, and insects. Seasonal changes in species diversity were observed, with the highest values recorded in autumn (2168.7 ind./m², 1.4 g/m²) and spring (580 ind./m², 6.01 g/m²). These patterns may be explained by the replenishment of the lake by the Zhaiyk (Ural) River and increased precipitation. In addition, the obtained results were compared with published data, and the level of species similarity with several lakes of the West Kazakhstan Region was determined. It was established that the taxonomic diversity of Lake Kolovertnoye is at a moderate level compared to a number of water bodies of the West Kazakhstan Region. According to studies conducted in the region, a total of 82 taxa belonging to the groups Oligochaeta, Hirudinea, Bivalvia, Gastropoda, Crustacea, and Insecta were identified in benthic samples. Among them, oligochaetes were represented by 2 species, leeches by 1 species, bivalves and gastropods by 3 species each, crustaceans by 7 species, and insects by 66 taxa.