Mass Balance Simulation for Wetlands and Estuaries Management

Abstract

The closed bay formed by a tidal power plant on the west coast of Korea has caused water quality to change due to nutrient increase and salinity alternation. The nutrients of the inner bay are often kept a balance with the aid of the outflow at the mouth of the bay. Hence it is necessary to minimize the environmental effects by forecasting the potential environmental changes caused by a tidal power construction. Seasonal observations of mass balance in the inner and outer Garolim Bay were performed.  The low quality nutrients released from sediments, land and river were more dominant than the nutrients released from the outer bay in the study area. It was observed that the tidal power plant construction made water exchange ratio 57%.Various mitigation strategies such as water gates were studied so that the water exchange rate can be reduced. The change in the water exchange ratio is significantly reduced as the cross-section and the number of water gates is increased. The water exchange ratio was decreased by 8%, which increased nutrients in the inner bay. Results of numerical the nutrients decreased with the 7% increase in the inflow while the decrease in outflow discharges. However, it is considered only 0.2% increase in the entire mass balance of Garolim Bay relatively inadequate to mitigate the environmental impact.