Scientific publications

Due to the fact that zones of ecological risk have appeared in Lake Ladoga since the increase in anthropogenic pressure in the 1970s, monitoring studies are currently needed to assess the ecological state of the littoral zone as the one that takes on the main anthropogenic load. The aim of the work was to assess the current ecological state of the waters in the littoral zone of Lake Ladoga in terms of toxicological and hydrochemical characteristics, and indicators of phytoplankton development, and to identify the most problematic zones of deterioration in water quality as a habitat for aquatic organisms. To assess the ecological state of the littoral zone, we used the following water quality criteria for water bodies of fishery importance: maximum permissible concentrations of heavy metals, petroleum hydrocarbons, pH, redox potential, indicators of phytoplankton development, trophic level, and toxicity indicators. It is shown that the areas of the most pressing environmental risk, as determined by the selected criteria, currently are: in the northern region – water areas near Impilahti Bay, Cape Umoppiumi, Kojonsaari, and Putsaari Islands; among eastern coast water – Uksunlahti Bay and Andrusovskaya Bay; among waters in the southern region – Volkhov Bay; among western coast waters – Taipolovsky Bay, Dalyokaya Bay, and Shchuchiy Bay. These water areas should be mandatory observation areas within the environmental monitoring system of Lake Ladoga with annual monitoring of toxicological, hydrochemical, and hydrobiological parameters. Considering the trophic scales used, the littoral zone of the western and southern regions of Lake Ladoga in 2019 can be characterized as weakly mesotrophic, the area along the eastern coast as mesotrophic-eutrophic, and the northern skerries region as mesotrophic. In general, according to the data obtained, the ecological state of the littoral zone of Lake Ladoga in 2019 can be said to have improved since 13 years ago (in 2006).