Mechanism of Cd Content Migration in Sea and Land

Abstract

based on the survey data of Cd content in Jiaozhou Bay in May, August and October of 1992, the paper studies the process of ocean current transport and the source of Cd content in Jiaozhou Bay. The spatial variation of Cd content from source transport in May, August and October is shown according to Dongfang Yang’s matter content migration rule, which is revealed with the model block diagram. The location, size, type and time scale of source of Cd content transport are also determined. There were three main sources of Cd content in Jiaozhou Bay, from run-off transport, river transport and main sea current transport. Rivers carried Cd content in excess of 0.96μg/L over the year, slightly polluting land and rivers. In addition, Cd content in run-off and main sea current was greater than 1.10μg/L, which means the whole land and ocean were slightly polluted by Cd content. Among rivers flowing into Jiaozhou Bay, there are four major rivers which carried Cd content into the waters of Jiaozhou Bay: Haibo River, Licun River, Loushan River and Dagu River. According to Cd content in the river, from high to low was: Dagu River > Licun River > Loushan River > Haibo River. The Cd content transport time scale of Licun River, Loushan River and Dagu River was the same, while that of Haibo River was shorter. The mechanism of land transport and sea transport is put forward by authors, and the mechanism of alternating migration of Cd content between land and sea is revealed. In May, the land began transporting large quantities of Cd into the sea; from May to August, the land transported Cd content to the sea for three months; In August, the transport from land to sea ended, and the main sea current began to transport Cd content in large quantities; from August to October, the main sea current transported Cd content to the ocean for two months; In October, transport of the main sea current ended, and rivers began to carry Cd to the ocean again. The Cd content transported by northern run-off in May was 1.10μg/L and the Cd content transported by main sea current in August was 1.11μg/L, which further confirmed the authors’ theory of matter uniformity. It can be seen that the Cd content transported by land and by sea was the same. Thus land and sea had the consistency of matter content.