TY JOUR TI Application of Fuzzy Logic for Estimation of Trends of Productivity Change in Some Areas of Lake Onego KW Lake Onego KW productivity KW fuzzy logic KW long-term dynamics KW eutrophication KW anthropogenic impact JO Russian Journal of Earth Sciences AU Korosov, A.V. AU Kalinkina, N.. AU Tekanova, E.. AU Syarki, M.T. AU Isakova, K.V. AU Makarova, E.M. PY 2025 IS 25 PB Geophysical Center of the Russian Academy of Sciences