한국 경기만과 태안만 표층퇴적물의 유기물 분포 및 기원

Abstract

Organic carbon and total nitrogen stable isotopo ratros as well as aliphatic hydrocarbon are determined understand the source of sediment in western coastal region (Gyeonggi Bay and Taean Bay) of Korean Peninsula. The isotopic composition of organic matter (δ13C and δ15N), total organic carbon (TOC) and total nitrogen (TN) content of surface sediments from Gyeonggi Bay (n=50) and Taean Bay (n=61) were determined. The δ13C and δ15N values in both bays indicate that the surface sediment include a mixture of terrestrial and marine organic matter. High TOC and TN contents were also observed at the mouth of the bays and decreased offshore. The distribution of total organic carbon is strongly correlated with the sediment grain size exhibiting the fine sediment generally has high organic carbon content. The C/N ratios decreased toward the central Yellow Sea with a dominance of marine organic matter in Taean Bay. We found a weak correlation between C/N ratio and isotopic composition. It seems to be due to refractory portion of the altered organic matter and influence of inorganic nitrogen on C/N ratio. n-alkane composition showed a mixture of terrestrial and marine source with a predominance of marine organic matter showing two maximum peaks at C12 and C14 in Gyeonggi Bay surface sediments and a maximum peak at C10 in Taean Bay surface sediment