新泰市农田重金属污染现状及评价

Status and Evaluation of Heavy Metals Pollution in Farmland Soil of Xintai City

对新泰市农田土壤中Cu、Zn、Pb、Cd、Cr、Ni、Hg、As进行测定分析,利用单因子评价和多因子评价方法来评价土壤重金属的环境质量,并在GIS软件支持下,通过空间差值分析了研究区重金属含量的空间分布特征。结果表明,除Zn和Cd的个别采样点超标外,其余6种重金属的含量均在《土壤环境质量标准》(GB15618-1995)二级标准的限值内;从土壤重金属空间分布来看,Zn和Cd的空间分布极其相似,其余6种重金属的分布各有规律,存在显著的空间分异。由此得出,引起新泰市农田土壤质量下降的主要原因是Zn和Cd的污染;该研究采用的评价标准是《土壤环境质量标准》(GB15618-1995)二级标准,如以当地的土壤元素背景值作为评价标准则该地区的土壤污染将严重得多。

The contents of heavy metals （ Cu,Zn, Pb, Cd, Cr, Ni,Hg and As） in farmland soil from Xintai were analyzed. Single factor evaluation and multi-factor evaluation methods were used to evaluate the environmental quality of heavy metals in soil. Based on GIS,the spatial distribution characteristics of heavy metals content in the study area were analyzed by using space interpolation. The results showed that the content of heavy metals were all in the range of the critical values of the secondary standards of National Soil Environmental Quality Standard（ GB15618-1995 ）, except fur Zn and Cd. From the space distribution of heavy metals,the space distribution of Zn and Cd were very similar,the distribution of other heavy metals had their laws （ with obvious space difference）. Therefore ,Zn and Cd were the dominant elements causing soil heavy metals pollution in the study area. Evaluation standards used in the study were the secondary standards of National Soil Environmental Quality Standard（ GB15618- 1995 ）. The soil poUution would be more seriousl if evaluation standards were the background values of local soil elements in the area.