Modeling of Lake Ladoga Ecosystem Transformation under Decreased Phosphorus Load

摘要

Lake Ladoga, the largest lake in Europe, is one of the northernmost great freshwater basins of the world. It is located between 59°54' and 61°47' N. Its spacious size (surface area 18 000 km~2, water volume 908 km~3), cold waters, and intensity of mixing a priori provided grounds for the assumption that this basin will avoid the fate of the American Great Lakes Erie and Ontario, which suffer anthropogenic eutrophication. Nevertheless, the growing phosphorus load on Lake Ladoga since the 1960s resulted in its transformation from the oligotrophic to mesotrophic state by the early 1980s. Phosphorus is responsible for the transformation of the Lake Ladoga ecosystem [1, 2].