specific composition

SALINITY INFLUENCE ON CHIRONOMID LARVAE (DIPTERA, CHIRONOMIDAE) IN THE CRIMEAN HYPERSALINE LAKES

The paper summarizes the results of our long-term research (2007 - 2015) of chironomids in 38 saline and hypersaline lakes in the Crimea. Chironomid larvae were found at salinities up to 340 g/l, and their occurrence frequency decreased as salinity rose above 30 - 50 g/l. Four species, namely, Baeotendipes noctivagus, Cricotopus gr. cylindraceus, Tanytarsus gr. Mendax, and Paratanytarsus gr. quantuplex were identified.

SPECIFIC COMPOSITION AND ABUNDANCE OF THE WINTER ZOOPLANKTON IN THE RYBINSK RESERVOIR

The specific composition, seasonal dynamics, vertical and horizontal zooplankton distribution were studied in the pelagic zone and littoral of the Rybinsk reservoir in the winters of 2008 – 2016. The zooplankton abundance was found to be low (the abundance < 10,000 ind./m3, the biomass < 0.1 g/m3), by an order of magnitude lower than the values recorded in the 1970 – 1980s. As earlier, the abundance peak was observed in March. The cryophilic Cyclops kolensis prevailed among the crustaceans. A reproducing population of C.