Application of EFDC model to grading the eutrophic state of reservoir: case study in Tianjin Erwangzhuang Reservoir, China

Reservoirs are major sources of water supply in many densely populated areas. Eutrophic state plays an important role in reflecting the health status of reservoir ecosystem and it is a key field of water environment study. In this paper the method of grading the eutrophic state of reservoir based on the results of Environmental Fluid Dynamics Code (EFDC) model was proposed in order to obtain the spatial and temporal evaluation of eutrophic state in reservoir. Taking Tianjin Erwangzhuang reservoir as an example, the temporal and spatial trends of hydrodynamic and water quality of the reservoir were studied. The eutrophic state and the limited factor of eutrophication were predicted for Tianjin Erwangzhuang reservoir. This study provides a useful tool for understanding of the eutrophic state grade in a reservoir and surface water environment