Dynamics of biomass and area of overgrowing of aquatic vegetation of lake Kenon (Zabaikalsky krai) under conditions of water level decrease

Lake Kenon is used as a cooling reservoir for the Chita combined heat and power plant. Since 1979, the hydrological regime of the lake is regulated due to pumping water from the river. Ingoda. Significant volumes of pumped water contributed to the long-term maintenance of high-water levels. A decrease in volumes of pumped water against the background of a decrease in the amount of precipitation in the territory of Transbaikalia led to lower water levels in 2010-2015. The purpose of the work is to analyze the dynamics of overgrowth area and average annual values of macrophytes biomass, depending on water level fluctuations. Hydrobotanical work was carried out according to generally accepted methods. 109 stations were surveyed, 139 cuts were selected. It was revealed that with a decrease in the water level, the total area of overgrowth and the average annual values of the macrophytes biomass increase, especially for submerged plants. At the same time, the reaction of ecological groups of aquatic plants or specific plant species to fluctuations in water levels is different. In general, despite the significant anthropogenic load, Lake. Kenon retains the status of a macrophyte reservoir with the dominance of charophytes, Stuckenia pectinata and Myriophyllum sibiricum.