Hydrobiological characteristics of the Don River in the region of the Bagayevsky hydroelectric complex construction

Abstract

The data on the taxonomic composition and quantitative characteristics of planktonic and benthic communities of the Lower Don in the area of construction of the Bagaevsky hydroelectric complex have been presented. In June – July 2018, a comprehensive hydrobiological survey was carried out to assess the taxonomic composition and quantitative characteristics of phytoplankton, zooplankton and zoobenthos. Hydrobiological samples were taken at 21 stations using standard techniques. The phytoplankton communities contained 110 taxa, zooplankton – 58, zoobenthos – 78. The spatial distribution of quantitative indicators of plankton and benthos in the investigated area has been presented. Phytoplankton abundance varied from 2,006.0 to 6,128.0 million cells/m3, biomass – from 1.00 to 7.37 g/m3, the average polygon indicators were 3,636.6 ± 223.5 million cells/m3 and 4.28 ± 0.39 g/m3 respectively. In terms of the number of registered taxa and quantitative indicators, two groups of phytoplankton dominated – cyanobacteria and green algae. The abundance of zooplankton ranged from 2,580 to 238,622 ind./m3, biomass ranged from 36.4 to 476.0 mg/m3, the average abundance was 74,690 ± 15,017 ind./m3 and 172.7 ± 24.8 mg/m3 respectively. Rotifers and cladocerans were the leaders in the number of species. Meroplankton was dominant in numbers (mainly due to mollusk larvae), and copepods were the dominant group in biomass. The number of bottom invertebrates varied from 20 to 17,867 ind./m2, biomass from 0.02 to 2,114.0 g/m2, the average zoobenthos abundance was 3,462 ± 898 ind./m2, biomass 133.9 ± 102.0 g/m2 respectively. The maximum number of taxa was recorded among crustaceans and chironomid larvae. The basis of abundance was formed by oligochaetes and insect larvae, mainly chironomids, mollusks dominated by biomass. The resulting materials can be used as background materials in assessing the impact of construction on the hydrobiological communities of the Lower Don

Keywords

• phytoplankton
• zooplankton
• zoobenthos
• the don river
• laonome xeprovala
• фитопланктон
• зоопланктон
• зообентос
• река дон