| This paper investigates heavy metals (Hg,Cu,Pb,Zn, Cd, As ) in the water and sediments of Bohai Bay in Tianjin , studies their contents and spatial distribution. The collective distributing trend of the elements is analyzed in the base of the study on their correlation analysis. The mineral combination of the sediments is also analyzed in order to find out their geochemical characteristic. In the end, the assessment of heavy mental of the research region is discussed. The results indicate that:The heavy metals pollution level is under the standards for seawater quality of the first category, and belongs to the contents range of normal seawater. Because of the complicated water circumstance and the influence of varied pollution source, it is difficult for the level distribution to form a certain feature.The average contents of heavy metals in the sediments are much higher than the background. It indicates Bohai Bay has accumulated a mass of heavy metals in the past several years. Compared with the background, the average contents of Hg and Zn in every station are in excess of the standards, the average contents of Cu in some stations are in excess of the standards, and others are not.As a whole, the characteristic of level distribution of heavy metals in the sediments shows that the contents near the estuaries are higher. The Vertical distribution is hard to form a certain feature because the samples of column are too short.The correlation of these heavy metals in this sea area is very evidence, which reflects their concomitant geochemical characteristic.Only in the monitoring stations of the first category, synthetic pollution indexes of heavy metals in sea water are between 0.5 and 1.0 at effect degree. The pollution indexes in other stations are less than 0.5 in the allowable range. The heavy metals pollution in sediments is much severer and seriously harmful to ecology in most stations. Hg is the primary element of pollution.
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