Zooplankton of some rivers of the Podkamennaya Tunguska river catchment (Yenisei river catchment)

Abstract

The article reports the results of studies of zooplankton communities сonducted in 2017–2020 in some rivers of the Podkamennaya Tunguska river catchment. Zooplankton samples were selected and processed according to generally accepted methods. The taxonomic composition was determined for the first time (except for the Kamo River). The taxonomic composition included 48 taxa: Rotifera — 21, Cladocera — 16, Copepoda — 13. The greatest species diversity of zooplankton was recorded in the Tohomo, Tetere and Taiga rivers — 18–26 taxa, the smallest — in the Ter, Levoe Cheremo and Levaya Tokura rivers — one species each. In most rivers there were rotifers Euchlanis dilatata, and crustaceans — Acroperus harpae, Chydorus sphaericus. In general, rotifers and cladocerans played a significant role in the zooplankton of the studied rivers. The average abundance and biomass of zooplankton organisms varied from 22 to 2673 ind./m3 and from 0.001 to 29.63 mg/m3, respectively. Zooplankton was most developed in the Tetere river due to the abundance of large cladoceras of the genus Alona, Daphnia longispina, Eurycercus lamellatus, Simocephalus vetulus. Low the average abundance was in the rivers Maliy Yurubchen, Levaya Tokura, biomass — Verhvnya Madra, Dugungna, Maliy Yurubchen, Yurubchen, Tes, Levoe Cheremo, Levaya Tokura characterized by a relatively high flow rate and limited supply of organic and biogenic substances that determine the development of the invertebrate food supply. According to the quantitative characteristics of zooplankton, the rivers of the Podkamennaya Tunguska river catchment are characterized as poor in feed.