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A large number of mining transport emissions of heavy metals , pollution of the surrounding environment and pose a serious health threat . In this paper, Hunan Lengshuijiang tin mines surrounding areas targeted by the field survey , grid sampling , Determination of heavy metals as well as all the classic statistics, geostatistics and ecological risk assessment , study sources of heavy metal pollution in the area and spatial distribution . Tin mining smelter in the area around 98 square kilometers of soil samples collected within the total 83 , 23 plant samples using ICP-OES instruments to measure samples Cd, Cr, Cu, Pb, Zn content of five elements , AFS- measurement sample in the instrument 820 Sb, As, Hg content . Through correlation analysis, principal component analysis and cluster analysis of the results showed that : As, Zn, Cu, Pb pollution sources from the same area of ??the probability of large , Cr may be derived from the soil parent material, may exist within the region other than the Sb smelter , Hg, Cd pollution. Sb, As, Pb, Zn, Hg, Cd smelter obviously closer distance the higher the degree of pollution trends ; smelter dust Tailing diffusion may cause Cd, Sb and Hg superimposed pollution. The choice of different plants absorb different heavy metal , heavy metal content of plants in different parts of the order except Sb, Cd showed aboveground gt; underground part , Cr, Pb, Hg, As showed an underground gt; shoot . Compared in terms of plant roots to absorb foliar absorption of heavy metal accumulation in plants is also an important way . Potential ecological risk factors in the order of Cd gt; Sb gt; Hg gt; As gt; Pb gt; Zn gt; Cr, the total potential ecological risk classification as severe , including Sb, Cd, Hg risk serious ; Pb, As pollution also poses a potential threat. The overall results show that tin mining smelter surrounding soil has been Sb, Cd, Hg serious pollution , the application potential ecological risk index for mining ecological risk of heavy metal pollution evaluation results show that , with the exception of one sample point away from the mine , each sampling points are up moderately severe or severe ecological hazard level , and Sb, Cd, Hg of the most serious hazards . Within a radius of 10km is not suitable for agricultural production activities.
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