| Coastal area is a complex and dynamic environmental system, which receives lots of terrestrial pollutants. These pollutants include not only minerals but organic pollutants, which influence the marine environment seriously. In this dissertation, we studied the distribution characteristic and contamination of dissolved heavy metals and organic pollutants, behavior of suspended particle matter (SPM) heavy metals, the time and space distribution of heavy metals in sediments, assessment of sediments quality and potential influence on organisms, enrichment of heavy metals in marine bivalves. The main results as follows: Values of heavy metals and organic matters in surface water of Jiaozhou Bay did not exceed Water quality criteria. The contents of total Hg, Cd, Pb, Zn, Cu had no notable changes with time, while petroleum and Anionic surfactants did. In Jiaozhou Bay, the water quality was low contamination. But in Haipo river mouth and Huangdao ferry areas, the surface water was contaminated severely. Most pollution variables were not contaminated except for Pb and Zn. In this study, the contents of SPM were low. The seasonal changes were: spring >winter>autumn>summer. In some area, high concentrations were found closed to coast and low levels were obtained far from coast. The levels of SPM heavy metals were not in proportion, a clear relationship also existed between the decrease in concentrations of Cu, Zn, Mn and distance from the coast. The negative relationships between all metals and SS showed the impact of sediment re-suspension on SPM metal concentrations. In Jiaozhou Bay, the dissolved Zn, Cu, Cd was dominant, while Pb was mainly in SPM. The equilibrium distribution of metals in both SPM and water has been determined. The calculated results demonstrate that log (Kd)Pb > log (Kd)Cu , the rank was due to the specific characteristics of each metal. For Pb, its high particle reactivity promotes association with particulate matter, while, in contrast, low particle reactivity and a stronger potential to form stable complexes allow Cu to remain in the dissolved phase. As a whole, Cu, Zn, Pb, Cd, Hg Cr mainly distributed at the eastern part of Jiaozhou Bay-river outfalls, Qingdao harbor and their adjacent sea areas. But As was a exception. The higher As value observed at the Dagu river mouth. Compared to previous reports, the distribution trend was similar; however, all mean values were higher in this study. On the basis of sediment quality, the Zn concentration in sediments was ≦150 mg/kg; Cu, Pb, Cd, Hg contents in sediments from river mouth areas ranged from 100-200 mg/kg, 130-250 mg/kg, 1.50-5.00 mg/kg, 0.50-1.00 mg/kg; As and Cr were ranged from 65 to 93 mg/kg and 120 to 270 mg/kg. The enrichment of metals in sediment core from rover mouth area was serious, indicated that more serious pollution in coast. Most metals from other areas were low and moderate contamination. Principal component analysis (PCA) was applied to estimate the sources of heavy metal contamination. Results that the first three components accounted for 52.61%, 17.37% and 15.60% of the total variance respectively exhibited that industrial wastewater, degradation of organic matter and erosion of rocks were the main sources of heavy metal contamination. Marine sediment pollution indices and mean sediment quality guideline quotient were applied to assessed sediments contamination and potential effects to organisms. Results showed that sediments were in good and average condition and had a moderate potential for observing adverse biological effecets.The concentrations of Cd, Zn and Pb in organisms did not exceed the maximum permissible levels (MPLs) of 2 μg/g Cd, 2.0 μg/g Pb and 100 μg/g Zn according to the codes of WHO. But Cu contents of most samples exceeded the MPLs (10 μg/g). In bivalves, the geographical pattern was not clear as that of sediments, while some trace elements show a clear relationship with clam age. The metal transfer factors told no considerable biomagnification or bioconcentration from water to bivalve molluscs was recognized; instead biodiminution was the prevailing process. The exception was the slight enrichment of Cd from particulate matter to molluscs and Cd from sediment to molluscs.
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