Seasonal-vertical variations of Pb and their mechanisms in marine bay

This paper analyzed the content, distribution, seasonal and vertical variations of Pb in Jiaozhou Bay based on investigation data in surface and bottom waters in different seasons in 1982 and 1983. Results showed the seasonal variations of Pb contents in surface and bottom waters were consist in generally. However, in case of Pb contents were high enough in summer, a large amount of Pb was absorbing and settling to the sea bottom under the force of gravity and current was the horizontal settling process of Pb, resulting in the higher Pb contents in bottom waters in autumn. The seasonal variations of Pb content in surface waters in Jiaozhou Bay were mainly determined by the variations of Pb source, while in bottom waters were determined by the Pb contents in surface waters and the vertical water's effect.