Distribution and influence factor of Cu, Pb, Hg in surficial sediments and suspended sediments of Hangzhou Bay

Heavy metals (Cu, Pb, Hg), grain size parameters, total nitrogen, total Phosphorus, total carbon of 18surface sediments and suspended sediments of Hangzhou Bay were measured to obtain the spatial distribution and influencing factors and based on the 3-D current field established by FVCOM and P-M sedimentary dynamic environment analysis, the role of dynamic deposition in the aggregation of heavy metals was emphatically analysed. In the surface sediments, the maximum value of Cu, Hg appeared in the middle of the bay mouth, while the maximum value of Pb appeared at the north side of the Bay mouth, the contents in the top mouth was much lower, middle of bay mouth was important collection area of Hangzhou Bay. The contents of metals in suspended sediments were slightly higher than in surficial sediments, the discreteness was much smaller and the distribution was much more uniform. The differences of heavy metals in suspended particulate matter and surface sediments reflected the interaction of the sediment discharge from the Yangtze River Estuary and the discharge from the north shore of the Gulf of Hangzhou. The hydrodynamic effect of study area was very strong, the sedimentary differentiation caused by the circulation of tidal current was one of the most important reasons for the different concentrations and discrete difference between suspended sediment and surface sediment. Organic matter played an important role in the enrichment of metals in the surface sediments. © 2017, Editorial Board of China Environmental Science. All right reserved.