행암만의 퇴적환경특성

Abstract

Haengam Bay is possibly polluted by the discharge of large quantities of effluents from the industrial facilities, harbors and domestic swage. The surface sediments were taken for grain size, geochemical and foraminiferal analyses in August 2001 in order to investigate of sedimentary environment in the bay. Twenty surface sediments dominated very poorly sorted muddy sediments and consisted of three sedimentary facies. The probable source of muds was from the Nakdong river. Twelve surface sediments were collected to examine the state of heavy metal pollution. The heavy metal concentrations in surface sediments were relatively higher than those in the other bays in Korea. Cu, Zn and Pb were more concentrated than those in Masan Bay. Generally, the heavy metal concentrations increased from the bay mouth to the inner bay. Sixty four foraminiferal species were recorded in total assemblages of surface sediments from 12 stations, including 8 species of living population. The general characteristics of total benthic foraminifera in the study area were reflected in sedimentary pollution. Eight stations among 12 stations could not find any living foraminifera. In the inner bay, the number of individuals and species number especially had lower values than those in outer bay. Trochammina pacifica and Eggerella advena, the opportunistics in polluted area, were among dominant species in the study area. The relationships between Cu, Zn and Pb concentrations and foraminiferal individuals and species numbers showed that the foraminiferal specimens decreased with increasing Cu, Zn and Pb concentrations. The higher heavy metal concentrations were one of the factors for decreasing foraminiferal specimens.