On the usage of the data on the parasites of fishes in exploring typologic status of the lakes in the North of Europe

This work is devoted to the investigation of typological status of lakes in the North of Europe (on the example of inland water bodies of Karelia and the Kola Peninsula). For that purpose, the parasites of fishes are used as ecological criteria. It is shown that the eutrophication and dystrophication are the main natural processes defining the development and typology of lakes. They occur concurrently and directionally, but they are not identical in different lakes. Parasites of fishes serve as reliable ecological indicators of these processes.