새 萬金干拓事業地區 淡水湖의 水質豫測 = Prediction of the Water Quality in the Estuarine Lake of the New Mankeum Tidal Land Reclamation Project

다국어 초록 (Multilingual Abstract)

A method for predicting the salt water exclusion process or the time-varying salinity in an estuarine reservoir system is presented, which may be a powerful tool when the reservoir flow is well mixed and predominently one-dimentional. The method that views the reservoir as a one-dimentionally distributed system is a great improvement over the one based upon the salt balance equation for a lumped system. Coupling the open channel flow equations with the convection-dispersion equation, the flow of water and the transport of water density are simultaneously analyzed in terms of the interaction between water movement and density. The quasilinealized basic equations to be solved are cast into numerical versions by use of the finite element method and the implicit time integration scheme to build a versatile and tough model for salinity and flow prediction. Inclusion of time-dependent local injection of withdrawal of water and salt in the model is done by boundary and lateral flow treatments. The method presented in this paper is applied to the new Man-Keum estuarine reservoir in Korea, now under construction. The result of 5 year consecutive analysis after the construction of the polder dikes shows that the predicted salinity is allowable for irrigation at the sites of pumping stations located far downstream of the two main rivers, Man-Kyeong and Dong-Jin.