Almost half of the Pb content leaving in the bottom of the sea

Abstract

Using survey data of Pb in water body from southwest of Jiaozhou Bay to west of bay mouth, in August 1992 and according to the horizontal change model and the vertical change model of matter content put forward by authors, we calculate the horizontal loss amount, vertical diluted amount and vertical sediment amount of Pb in surface and bottom layer and determine the model diagram of Pb content horizontal and vertical changes. The results showed that in August, the absolutely horizontal loss amount of Pb content in surface layer and bottom layer was 8.92μg/L, and the relatively horizontal loss amount of Pb content was 56.10%. The absolutely horizontal increase amount of Pb was 5.74μg/L in bottom layer, and the relatively horizontal increase amount was 42.23%. In the southwestern waters of the bay, the absolutely vertical diluted amount of Pb was 8.05μg/L in both surface and bottom layer, and the relatively vertical diluted amount was 50.62%. Meanwhile, in the western waters of bay mouth, Pb content in the surface and bottom layer had an absolutely vertical sediment amount of 6.61μg/L and a relatively vertical sediment amount of 48.63%. From the southwestern waters of the bay to the western waters of the bay mouth, a large amount of Pb content in the surface layer is deposited on the seabed. Therefore, during the horizontal migration of Pb content on the surface, the loss was nearly 60.00% when the current left the bay. However, Pb content in the bottom layer increased by 42.23% during its horizontal migration. Thus, the high Pb content in the surface layer is retained at the bottom of Jiaozhou Bay. When the current left the inside of the bay, Pb content in the surface layer was relatively high with the vertical diluted amount of Pb content in the surface layer and bottom layer reaching almost 50%. When the main sea current reached the western part of the bay mouth, the Pb content in the surface layer could settle on the seabed rapidly and continuously with a high sediment amount of 48.63%.