ACCUMULATION OF HEAVY METALS Pb,Zn AND Cu IN WANGGANG TIDAL FLAT OF JIANGSU PROVINCE

This paper discusses the temporal distribution of heavy metals and associated pollution in the Wanggang tidal flat area of Jiangsu Province. It was found that the vertical content of heavy metal in Wanggang tidal-flat has the same tend of decreasing from surface layer to bottom gradually in accordance with granularity.There was more argument that heavy metals and granule sediment had good relativity. It was known from the relativity of heavy metals that Fe,Ni,Cr,Mn,Pb,Zn,and Li had better relativity. Comparatively the relation among Fe,Ni and Cr was very remarkable,exceeding 0.900. It was obvious that those heavy metals were relatively steady and possibly came from rock.Pb,Cu and Al have minus-correlation with Fe,indicating that Pb and Cu of Wanggang tidal flat were affected by artificial factor. After standardization, normalization of Cu and Zn is in stabilization. Cu was confined in 0.4~2, and Zn in 1.5~2.6. But Pb has big fluctuation with time. Using the latency zoology index method lodged by Hakanson,we know that the latency zoology index of Pb,Cu and Zn was less than 95, and the latency zoology harm was light. But this was influenled by Pb and Cu pollution,and Pb and Cu were the most serious polluting factors in the study area. Traffic gas and waste water from metallurgy industries and also pesticide and fertilizer were mostly the reason of heavy metal pollution. It is suggested that the environmental pressure due to heavy metal in Wanggang tidal flat comes from pollution of cover fountain in farming.