Abstract
In this study, the effect of integration of river model and estuary model was evaluated to demonstrate the benefit of an integrated estuary model. An integrated estuary model consits of hydrological model, estuary model and meteorological model. In general, salinity distribution may be found to be significant for the evaluation of long-term water quality in an enclosed bay because salinity mainly controls density in a bay. Therefore, the influence of tide on salinity in a bay was investigated to demonstrate the necessity of an integrated estuary model. Two different river discharges and three different tidal amplitudes were used to examine the influence of tidal effect on salinity flux at the mouth of river. It was revealed that, for the case where river discharge at the upstream end of river model is constant and river discharge due to tide is included, with increasing reduction of average salinity from initial conditions, the river discharge at the upstream end was smaller than river discharge due to tide. The integration of river model, which can include the feature of estuary, and estuary model is, thus, found to be important to evaluate salinity flux at the mouth of river accurately.
