The Low Cadmium Content Discharged in Jiaozhou Bay

Abstract

In May, Augustand October of 1991, the variation range of Cd content in Jiaozhou Bay was 0.06-0.58μg/L, which meets the water quality standard of this kind of seawater. It indicated that in terms of Cd content, the water of Jiaozhou Bay was not polluted by Cd in May, August and October. There were four sources of Cd content in Jiaozhou Bay: river streams, ships and wharfs, atmospheric sedimentation and overland runoff. The Cd content from river streams was 0.38-0.55μg/L, 0.48-0.58μg/L from ships and wharfs, 0.40μg/Lfrom atmospheric sedimentation, and 0.52μg/Lfrom overland runoff. This showed that these four sources were not polluted by Cd content. The Cd content of human emissions mainly included land, ocean and atmosphere with an order of ocean> land >atmosphere. Besides, the Cd content of three emissions were less than 1.00μg/L, which indicated that land, atmosphere and ocean were not impacted by Cd content. The transport passages of Cd content were different, whereas, the Cd content of marine waters was almost consistent, and Cd contents by three different transport were less than 0.20μg/L. Finally, the modelling chart wasfurther built to display the transportpassages of Cd content, anddisclose the transport of Cd content from human emissions to land, atmosphere and lastly ocean in a quantitative way.