Author:
Yang Dongfang,Zhang Longlei,Wang Qi,Ling Weifeng,Li Haixia
Abstract
Abstract
Applying the survey data of the Cd content in the water of Jiaozhou Bay in October 1992, from the southern waters of the bay mouth to the southeastern waters, the author calculates out the horizontal loss amount, the vertical disputed amount and the vertical sediment amount of the Cd content in the surface and bottom of the water body and determines the model block diagram of the horizontal and vertical changes of Cd content, based on the content changing models of the horizontal matter and the vertical matter proposed by the author himself. The calculation results show that in October, the absolutely horizontal increase amount of Cd content in the surface and bottom layer is 0.12-0.89μg/L, and the relatively horizontal increase amount of Cd content in the surface and bottom layer is 23.52-74.78%. In the southern waters of the bay mouth, the Cd content in the surface and bottom layer has an absolutely vertical disputed amount of 0.09μg/L, and its relatively vertical disputed amount is 23.07%. In the southeastern waters of the bay, the Cd content in the surface and bottom layer has an absolutely vertical sediment amount of 0.68μg/L, and its relatively vertical sediment amount is 57.14%. There is the Haibo River near the southeastern waters of Jiaozhou Bay. In October, the Cd content of the Haibo River is 0.51μg/L, which is higher than the Cd content of 0.39μg/L carried by ocean currents. It provides a lot of supplements to the ocean currents passing the southeastern waters of the bay. During the horizontal migration of the Cd content in the surface and bottom layer, Haibo River supplements the Cd content in the ocean current with the loss and increase of the surface and bottom layer. Through the horizontal changing model of matter content, the horizontal increase of the surface Cd content is calculated. The absolute increase of the Cd content is 0.12μg/L, and the relative increase is 23.52%. Similarly, the horizontal increase of Cd content in the bottom layer is calculated. The absolute increase of Cd content is 0.89μg/L, and the relative increase is 74.78%. During the vertical migration process, the vertical change of the Cd content in the southern waters of the bay mouth and the southeastern waters of the bay reveals the following law: when the surface Cd content is low, the waters present a vertical dilution of the Cd content at the surface and bottom layer, and there is no Cd content accumulation on the seafloor. When the Cd content in the surface layers is high, the waters present a vertical accumulation of Cd content in the surface and bottom layers, and there is an accumulation of Cd content on the seafloor. According to the formula for calculating the Cd content of river sources proposed by author himself, the Cd content of the surface of Haibo River source from land is calculated to be 1.01 μg/L.