Issues:
Sections:
Issue 97
GENERAL BIOLOGY
UDK: 581.526.325.2
SEASONAL DYNAMICS OF THE SPECIES STRUCTURE AND QUANTITY DISTRIBUTION OF PHYTOPLANKTON IN THE CHIRKEY RESERVOIR
AMAEVA Frangiz Shamilievna,
OSMANOV Magomed Magomedovich,
ALIGADZHIEV Murad Mukhtarovich,
ABDURAKHMANOVA Ayshat Abdulmajidovna
The species composition of phytoplankton and its seasonal changes in the aquatic ecosystems of the Chirkey Reservoir were investigated in the summer and autumn of 2024. A total of 25 species of microalgae were identified, belonging to three divisions: Bacillariophyta - 19 species, Cyanophyta - 3 species, and Chlorophyta - 3 species. The species diversity of phytoplankton in the study area ranged from 16 species (summer) to 12 (autumn), with diatoms (Bacillariophyta) comprising 60-80%. The peak vegetation of blue-green algae was observed mainly in mid-summer, when water temperatures were sufficiently high for their mass development. Diatoms formed the basis of the taxonomic composition, which changed depending on the season. The quantitative development of phytoplankton also changed in seasonal dynamics, decreasing from summer to autumn. The poor species diversity and low phytoplankton production in the Chirkey Reservoir were apparently associated with the conditions of its formation; low summer water temperatures in the reservoir and insufficient provision of nutrients did not contribute to intensive phytoplankton development. In the open part of the reservoir, brackish-water and euryhaline diatoms and blue-green algae constituted the main mass of phytoplankton throughout the growing season, while genetically freshwater green algae were found closer to the river part.
Pages: 21 - 26
Date: 30.08.2025