금강하구 부유사 변동특성에 관한 연구

Abstract

This study was conducted to figure out changes in suspended sediment and to propose sediment distribution characteristic, the summarized results of the study are as follows. (1) Average concentration of suspended sediment at all stations except for PC4(22 mg/l) is 186∼287 mg/l in the summer season and PC1∼PC3 are considered to be affected by the barrage discharge. In the winter season average concentration of suspended sediment at PC3(jetty end) and PC5(Janghang channel) is respectively 319 mg/l and 315 mg/l as relatively higher level compared to those in other stations, that may be because suspended sediment generated by waves and discharge forms complex phenomenon by tidal current and external force in Janghang entry route. (2) Sediment net flux and distribution of amounts of sediment which are field observed tend to be deposited by suspended sediment at PC1(Inner port channel), PC3(Jetty end), PC5(Janghang channel) affected by discharge flow and PC2(Kaeya Channel), PC4(Jetty enterance) affected by waves and tidal current. (3) Water flow was reproduced by using EFDC model, reliability of the model was proven through examining tide and tidal current. As a result of numerical experiment of sediment transport, it shows maximum distribution of amounts of sediment in Janghang entry route(PC3∼PC5). (4) Through the comparison with the amount of dredging and numerical model deposition distribution, reduced deposition due to the effects of dredged is 1.3 to 2.2 times. In conclusion, the Geum river estuary deposition movement is due to the impact of generic parts with similar behavior during ebb tide and discharge according to the direction of flow and sediment re-suspension of bottom sediments and artificial dredging.