지화학적 자료에 근거한 광양만 표층퇴적물의 특성과 저서환경

Abstract

A total of 110 surface sediment were analyzed in order to understand thege ochemical characteristics of the surface sediments and to evaluate the benthic environmental condition of Gwangyang Bay. The surface sedimentary distribution can be classified by five facies; mud (M), sandy mud (sM), sand (S), muddy sand (mS) and gravely sand mud ((g)sM). However, mud face is the predominant sedimentary feature of the Gwangyang Bay. The benthic environment based on total organic carbon/total nitrogen (C/N) and total organic carbon/total sulfur (C/S) ratios of organic matter showed that anoxic environment is prevailed in some parts of the study area because the C/S ratio of organic matter was higher than 2.8. The hydrogen sulfide (H2S) content showed extreme variability from site to site. It varies from 367 ppm to 1 ppm (average, 92 ppm). The inter-relationship of redox -sensitive elements (Mn, V, Mo and Cr) showed a relatively strong positive relationship with high accumulation in the sediment at the inner sites of the Bay (left of Myo Island). High content of TOC and hydrogen sulfide, and a high accumulation rate of redox-sensitive element were predominant characteristics in the sediments at the inner sites of the Bay (left of Myo Island), suggesting that this area is in an oxygen deficient, and potentially polluted condition.