抄録
Reservoir eutrophication brings deoxygenation of hypolimnetic water and high concentration of metal, nutrients and dissolved materials are released from the bed sediments. Production of dissolved materials then increases fluid density along the reservoir bed. On a sloping boundary, the heavy water mass generates an inclined thermosolutal plume that transports the polluted water and heat energy from the shallow layer to the deep layer. The authors found the plume is responsible for generation of stable salty water with inverse thermal stratification in the bottom layer.The present study is to develop a model that can reproduce eutrophication as well as seasonal variation of the thermal and salinity structure produced by this mechanism. The model is Lagrange-type based on a one-dimensional DY namic Reservoir Simulation Model, DYRESM. The original model was modified so that the thermosolutal convection and chemical and biological processes can be taken into consideration. The present model was verified through comparison between the simulation results and the field data.