抄録
This study was conducted to investigate the environmental factors affecting the phytoplankton (chlorophyll-a content) dynamics in Inohana Lake, Japan. Inohana Lake is a stratified estuary during summer, and eutrophication and the bottom hypoxia have occurred. A field survey was carried out in Inohana Lake during summer in 2007, and includes the water temperature, salinity, water density, the phosphate phosphorus, the total phosphorus, and chlorophyll-a concentrations. The meteorological factors include the wind, rainfall and solar radiation. Based on the water quality and meteorological data, the simple correlation and multiple linear regression analyses were used. The phosphorus flows into Inohana Lake through the river discharge. The PO4-P in the lake was sufficiently to use for phytoplankton growth and other factors rather than the phosphorus were proposed as limiting factors for phytoplankton growth. It was proposed that rain controls the phytoplankton (chl-a) dynamics bio-chemically by causing the phosphorus loadings through the river discharge and physically by changing the estuarine circulation and residence time. Wind also affects physically the movement of chl-a content by contributing to the mixing and exchange of water.
