새만금 방조제 건설에 따른 하계 유기물질거동 변화

Abstract

Particulate organic carbon(POC), dissolved organic carbon(DOC) and fluorescence dissolved organic matter(FDOM) in the Saemangeum area were observed from May 2003 to July 2005. There was a large variance in river discharge between the dry season and the wet season. Especially, in summer, the whole inside of Saemangeum dike has been affected by fresh water, and the influx of suspended particles and organic matters were increased because of land-derived organic materials. POC and SPM were removed from the surface water at the upper estuarine mixing zone of low salinity. DOC showed conservative behavior with the salinity gradient in the Saemangeum area, suggesting that physical mixing between seawater and freshwater dominates the distribution pattern of the dissolved organic carbon in the system. However, during dike construction, organic matters were increased in surface water in the northern part of the Saemangeum coastal water. The completion of the Saemangeum dike is likely to inhibit the exchange of materials between open ocean and the Saemangeum coastal water. This suggests that the oxidation of organic carbon in the bottom of the estuary may exhaust dissolved oxygen in the confined environment.