Cd Content with an Always High Vertical Diluted Amount

摘要

Based on the investigation data about Cd in Jiaozhou Bay in August 1992 and the horizontal change model of matter content and the vertical change model of matter content proposed by the authors, the horizontal loss amount, vertical diluted amount and vertical sediment amount of Cd content in the surface and bottom layers from the southeast waters of the bay to the west waters of the bay mouth were calculated, and the model block diagram of the horizontal and vertical changes of Cd content was determined. The results show that in August, the absolutely loss amount of Cd content in the surface layer was 0.09μg/L, and the absolutely increase amount of Cd content in the bottom layer was 0.10μg/L. The relatively loss amount of Cd content in the surface layer was 12.00%, and the relatively increase amount of Cd content in the bottom layer was 41.66%. Cd content in the surface and bottom layershadabsolutely vertical diluted amount of 0.42-0.61μg/L, and its relatively vertical diluted amount was 63.63-81.33%. In August, in the horizontal migration of Cd content in the surface and bottom layers, the main sea current carried high Cd content in the surface waters.And after passing through the nearshore waters of the bay, one tenth of the Cd content in the surface layer settled to the seabed. In the horizontal migration process of Cd content in the surface layer, the loss amount of Cd content in the surface layer reached 12.00% in the nearshore waters around Jiaozhou Bay, thus the increase amount of Cd content in the bottom layer reached 41.66%. It reveals that the high Cd content in the surface layer could rapidly and continuously sink to the seabed, and the Cd content in the seabed waters in Jiaozhou Bay increased by 41.66%. In August, in the process of vertical migration, the Cd content transported by main sea current was relatively high, and the vertical diluted amount of Cd content in the surface and bottom layers was high 63.63 - 81.33% from the southeast waters of the bay to the waters in the west of the bay mouth.