담수유입과 바람의 상호작용에 의한 폐쇄성 해역의 물질체류시간 수치예측

Abstract

The coastal sea were gradually polluted due to large scale of coastal development projects, reclamation and so on. Due to influx of pollutants through the river, eutrophication is getting worse. So contamination of coastal sea makes people get interest. In Masan bay, study area, the influx of freshwater to coastal sea is 765,000 t/day and average velocity near Masan port where contaminant influx is most high in Masan bay is weak about 2∼3 m/sec. It indicate through river near Masan port influx of contaminants is considerable but it is long to escape the Masan bay. And due to shallow water depth of study area the transportation of material is affected by wind stress easily. In this paper, we study the effects of freshwater influx and wind stress in residence time to understand long term material transportation. To understand the transportation we use the model and simulate the tidal currents. Then through the model, we calculate the residence time each particle escapes the area. The average residence time decreased about 10 days in upper area by freshwater and about 1 day in middle area by wind stress. And the result of interaction between freshwater and wind is similar to the result of freshwater effect. The results of simulation provide the spatial distribution of average residence time is controlled by freshwater and wind respectively. But the rate and range of effect of these factors are different.