By investigating the dataset Cadmium (Cd) in Jiaozhou Bay from 1984 to 1988, In the paper showed horizontal distributions of Cd, the major sources, and the changes of the major sources. Results unveiled that the major Cd sources during this time period were marine current, river discharge and atmosphere deposition, whose source strengths were 0.12-6.48 μg L −1 , 0.12-1.07 μg L −1 and 0.04 μg L −1 , respectively. During this time period, the source input from marine was sometimes weak and sometimes strong. The source input from river discharge was changing from little input to relative weak, and then to relative strong. The source input from atmosphere deposition was changing from little input to occurring finally. The human activities resulted in the increasing of the source input of Cd to the bay, and influenced the water quality continuously.

In this paper described the horizontal distributions of Petroleum hydrocarbon (PHC) in Jiaozhou Bay using investigation data on PHC in May, August and October 1991, and defined the major sources. Results showed that PHC contents in May, August and October 1991 were 0.014-0.157 mg L −1 , 0.010-0.058 mg L −1 and 0.007-0.064 mg L −1 , respectively. The pollution level of PHC could be considered as slight. The major sources of PHC were oil spills, wharf and river runoff, whose source strengths were 0.157 mg L −1 , 0.038 mg L −1 and 0.058-0.072 mg L −1 , respectively. The source inputs of PHC were showing spatial-temporal variations, and resulting in the spatial-temporal changes of PHC contents in Jiaozhou Bay.

According to the investigation data of Jiaozhou Bay in 1991, the current content and horizontal distribution of Cd contents in bottom waters from central to southern Jiaozhou Bay were studied in this paper. The results showed that in May, Cd content in this area was 0.06-0.10μg/L, and Jiaozhou Bay was not polluted by Cd content. In August, the range was 0.06-0.38μg/L, and Jiaozhou Bay was not polluted by Cd content. In October, the range was 0.26μg/L, and there was no pollution of Cd content in Jiaozhou Bay. Hence, in May, August and October, Cd contents in this area were low, far lower than 1.00μg/L, the Case I Sea Water Quality Standard. In terms of Cd content, water is clean, not polluted by Cd content. In May, in surface waters of bay center, there is not source to transport Cd content. In bottom waters from bay center to northern bay mouth, Cd content decreased from 0.08μg/L in bay center to 0.06μg/L in northern bay mouth along with the gradients. In August, Cd was high as0.40μg/L in surface waters of bay center, mainly from atmospheric sedimentation, which is relatively high. In bottom waters from bay center to northern bay mouth, Cd content decreased from 0.38μg/L in bay center to 0.16μg/L in northern bay mouth along with the gradients. In this paper, the impact of Cd contents from sources on bottom waters was studied. Besides, the horizontal variation of Cd contents disclose the variation of bottom waters influenced by Cd contents from sources.

According to the investigation data of Jiaozhou Bay in May, August and October of 1979, the vertical distribution and seasonal variation of water temperature at surface and bottom in inside and outside waters were studied, and the seasonal distribution, variation range and horizontal distribution trend were determined. The results showed that, in inside waters, bay mouth and outside waters, from May to August and to October, the seasonal variation was spring, autumn and spring, respectively, from high to low. It indicated that the water temperature was transported to everywhere in the ocean after the current transport in horizontal and vortex motion mixing in vertical direction. In terms of variation range, it was basically the same at surface and bottom in May, August and October. When it was low at surface, it was low at corresponding bottom; otherwise, it was opposite. From inside waters to bay mouth, the horizontal distribution of water temperature at surface was inconsistent with that at bottom in May, contrary in August and consistent in October. From bay mouth to outside waters, it was contrary in May, consistent in August and inconsistent in October. The horizontal distribution trend of water temperature disclosed that the source of high water temperature was the rising and decreasing heat.

The investigation dataset on Plumbum (Pb) in surface waters in Jiaozhou Bay in May and August 1990 studied the migration paths of Pb from source to ocean. The results unveiled that the major sources were port wharf, river flow, atmosphere deposition and marine current, whose source strengths were 13.39 μg L −1 , 12.97 μg L −1 , 11.01 μg L −1 and 10.82 μg L −1 , respectively. This paper revealed that there were three different migration paths which were described by a block diagram model. Finally, the migration laws of Pb from sources to ocean were defined that the loss of Pb contents were increasing along with the increasing of migration path. Ocean was the sink of Pb. During the migration path from source to sink, a part of Pb was storing in water body, while another part was settling and fixing in sea bottom.

Using investigation on Mercury (Hg) in May and August 1990, this paper analyzed the horizontal and vertical migration changes of Hg contents, and quantified the horizontal loss, vertical dilution and vertical accumulation amounts. Results showed that the absolute horizontal loss amount and relative horizontal loss amount were 0.002-0.015 μg L −1 and 3.63-15.87%, respectively. The absolute dilution amount and relative dilution amount were 0.000-0.005 μg L −1 and 0.00-2.57%, compared to absolute accumulation amount and relative accumulation amount of 0.008 μg L −1 and 12.69%, respectively. Once Hg was transporting through the bay, there were small horizontal losses in both surface and bottom waters. The horizontal loss in bottom waters would be small/big in case of the horizontal loss in surface waters was small/big. No matter Hg contents in waters were relative high or relative low, the sediment of Hg from surface waters to bottom waters was very rapid, and the vertical loss during the vertical migration process was very small, resulting in almost all of the Hg was moving to the sea bottom. Finally, this paper provided Yang's dynamic vertical balance theory to reveal the vertical migration process of substance in marine bay.