Abstract The research of phytoplankton abundance dynamics conducted in July- August 2019 at Lake Putus Pangkalan Baru village. A study aims to know the dynamics of phytoplankton abundance by spatial and temporal. There were 3 stations namely station 1 (inlet area), station 2 (in the middle of the lake) and station 3 (in the end of the lake). In each stations, there were 2 sampling point, i…