【摘要】 分析赣南某钨矿周边稻田土壤中镉、铅、铬、铜和锌等5种重金属的空间分布,采用地累积指数法和潜在生态风险指数法分析评价矿区表层稻田土壤中重金属的污染状况。结果表明,稻田土壤中表层、中层和底层重金属含量水平分布变化规律基本一致,在垂直分布上,随土壤深度的增加,重金属含量降低,镉和铅含量的空间变化均较大。表层稻田土壤中镉在全部采样点、铜在57%的采样点含量超过国家土壤二级标准,且镉严重超标。表层稻田土壤中重金属地累积指数污染程度强弱顺序为镉>铜>锌>铅≈铬,镉为中度至极重污染,潜在生态危害系数排序为镉>铜>铅>铬>锌,镉为高污染至极高污染,铜、铅、铬和锌危害程度较低。更多还原

【Abstract】 The spatial distributions of five heavy metals( Cd,Pb,Cr,Cu and Zn) in rice field soil around a tungsten mine in Gannan of Jiangxi are analyzed,and the heavy metals pollution situation in the surface layer of the rice soils around the tungsten mine is also assessed by geoaccumulation index( Igeo)and potential ecological risk index( RI). The results indicate that the horizontal distribution variations of the heavy metals contents are the same in all the three layers,the surface,the middle and the bottom,however,in the vertical distribution,the contents of the heavy metals are decreased with the increase of soil depth,and the spatial variations of the contents of Cd and Pb are remarkable. The contents of Cd in all the sampling sites and the contents of Cu in 57% of the sampling sites are more than the secondary standard limits of the soils,and the contents of Cd exceed the standard limits greatly. The pollution degree sequence of the heavy metals are Cd > Cu > Zn > Pb ≈ Cr by geoaccumulation index,and the pollution degree of Cd is from moderate to extreme high. The potential ecological risk indexes of the heavy metals are in the order of Cd > Cu > Pb > Cr > Zn. The pollution degree of Cd is from high to extremely high,and Cu,Pb,Cr and Zn are less harmful.更多还原