The Vertical Migration Characteristics of Zn in Jiaozhou Bay

Based on the investigation data on Zn in waters in May, September and October in 1983, were analyzed the horizontal distribution, seasonal variation and settling process of Zn in water in the bay mouth of Jiaozhou Bay, eastern China in 1983. Results showed that Zn contents in surface waters in May, September and October in the bay mouth of Jiaozhou Bay in 1983 were 1.96-117.50 mu g L-1, 7.14-42.50 mu g L-1 and 2.36-14.00 mu g L-1, respectively, while in bottom waters were 1.24-120.66 mu g L-1, 6.67-17.78 mu g L-1 and 4.72-20.44 mu g L-1, respectively. Hence, Zn contents in surface waters were in orders of spring > summer > autumn, while in bottom waters were in orders of spring > autumn > summer. The variations of Zn contents in bottom waters were consitent with in surface waters. In spatial scale, the contents and the variations of Zn in surface and bottom waters were closed. In regional scale, Zn contents in surface waters were higher than in bottom waters in case of high Zn contents, yet Zn contents in surface waters were lower than in bottom waters in case of low Zn contents. The vertical distributions and seasonal variations of Zn were the products of horizontal and vetical water's effects.