The seasonal variations of environmental factors and phytoplankton functional groups abundance and biomass among sampling sites. Water transparency (SD), water depth (D), electric conductivity (EC), dissolved oxygen (DO), pH, water temperature (T), total nitrogen (TN), total phosphorus (TP), N:P ratio (N:P), ammonium nitrogen (NH₄⁺-N), nitrate nitrogen (NO₃^‑–N) and chemical oxygen demand (COD_Mn).