부산대학교 도서관

Shihwa Lake is a brackish lake with high organic productivity and anoxic bottom waters. The high biological activity in surface waters along with limited vertical mixing has resulted in the development of an oxic-anoxic interface at the 3∼4m water depth. And anoxic bottom waters are enriched with PO₄, NH₃ and H₂S. Three sediment cores were collected from Shihwa Lake near the Banweol Industrial Complex in October, 1997 and were analysed for organic matters, S/C ratios, δ ^(13)C and heavy metals. The average S/C ratio was about 0.30 in the sediment cores, which is lower than 0.36, the characteristic ratio of marine sediments. Sediments appeared to be depleted in sulfur relative to organic carbon, and the total reduced sulfur showed high correlation with organic carbon. The δ ^(13)C ratios in the upper layer were slightly lower than those in the deeper layer. Heavy metals of Cr, Co, Ni, Zn and Cu showed high correlation with organic matters and with each other. Those metals have similar geochemical behavior. On the other hand, Mn, As, Cd and Pb showed low correlation with organic matters, showing that these metals may have different pathways and geochemical behavior from the former groups of metals. Heavy metal contents in the surface sediment of Shiwha Lake is also relatively high in comparison with obtained from inshore and offshore sediments of Korea.