진해만 입구해역의 표층 퇴적물 특성과 저서환경

Abstract

Surface sediments in the mouth area of Jinhae Bay were investigated to evaluate the benthic environment in terms of geochemical criteria and macrobenthos abundance. Characteristics of the surface sediment distribution exhibited muddy sediments in the most part of study area. Some mixed sediments of coarse sand and mud were distributed along the coastal area of Geoje island and around of Jeo islands. Organic matter based on ignition loss and total oragnic carbon from CHNS varied between 8.8% and 1.7%, 4.62% and 0.77%, respectively. The source of organic matter based on C/N ratio was considered to be mixed one with in situ biogenic and terrigenous organic matters. C/S ratio of organic matter also suggested that there was an anoxic bottom condition in several part of the study area. The content of hydrogen sulfide in surface sediment was extremely variable, and showed spatio-temporal variation from site to site. In several locations, the content of hydrogen sulfide as an index of eutrophication was over the critical value (0.2 mg/g), suggesting that several part of the study areas are not favorable for the habitat of macrobenthos. The relationship among the number of individuals of marcrobenthos, hydrogen sulfide and organic matter did not show a clear relationship, but showed a potential negative relationship between individuals of marcrobenthos and hydrogen sulfide.