城市表层土壤重金属空间分布特征

运用R软件和地统计学方法,对某城市土壤地表的As、Cd、Cr、Cu、Hg、Ni、Pb、Zn 8种重金属含量的空间结构特征进行了建模,研究了影响重金属空间结构的主要影响因素。结果表明,该城市土壤地表中8种重金属元素的变异函数理论模型拟合效果较好。除Cu、Hg外,其余6种重金属具有明显的空间变异性,工业区、交通区、生活区、公园绿地农药肥料等人为活动是造成重金属累积的主要原因。同时,该城市土壤地表存在重金属元素混合污染的潜在危害。

Spatial Distribution Characteristics of Urban Topsoil Heavy Metals

By using R software and the geo-statistical methods,a model was established for analyzing the spatial distribution features of eight heavy metals in urban topsoil and the main impact factors.The results showed that the experimental variogram models of the As,Cd,Cr,Cu,Hg,Ni,Pb and Zn in the topsoil fitted well.All the heavy metals,except Cu and Hg,showed obvious spatial variation,the accumulation of heavy metals was mainly caused by human activities in the industrial,traffic,living areas and the fertilizers and pesticides,and there was a potential risk of mixed noxious contamination of heavy metals.