城市工业园区土壤重金属含量的空间结构特征及分布规律

Spatial structure features and distributing rules of soil heavy metal contents of city industrial park

城市工业园区不断发展,园区内工、农业生产等人为活动造成园区内土壤环境质量不断下降,地表土壤重金属污染环境日益突出,揭示园区内地表土壤重金属分布规律及其主要影响因素,是城市工业园区土壤污染防治和修复的重要基础保障.以湖南省湘潭市工业园区为例,利用地统计学和GIS空间分析技术结合的方法,对工业园区地表土壤中6种重金属Cr,Cu,Ni,Zn,As,Cd的空间结构特征和分布规律进行了研究,研究结果表明:6种重金属中元素Cr,Cu,Ni,Zn符合正态分布,As,Cd符合对数正态分布.研究区内6种重金属元素的实验半变异函数理论模型拟合效果较好.Cr的变程最大,其空间相关距离达到了93.3 km.Cu,Zn,Ni,As的空间相关性较强,元素的空间相关性受人为因素的影响较小;Cr,Cd具有中等程度的相关性,其空间相关性受自然因素和人为因素的综合影响.城市土壤中As,Ni,Zn,Cd,Cu的含量分布与研究区内工业企业的分布有密切关系.

With the development of city industrial park and human activities such as industrial and agricultural production,the quality of soil environment of city industrial park was getting worse and worse. Revealing the distributing rules and main influence factors of surface soil were significant guarantee for the soil pollution prevention and remediation. The spatial structure features and distributing rules of six heavy metals of industrial park in Xiangtan city, Cr, Cu, Ni, Zn, As, Cd and their main influence factors were researched using geostatistics combined with GIS. The results showed that： Cr, Cu, Ni, Zn are normal distribution, and As, Cd obey lognormal distribution. The semivariogram theoretical models of six heavy metals in the study area are well fitted. The range of Cr is maximal and its spatial correlation distance reached 93.3 km. The spatial relativity of Cu, Zn, Ni, As are stronger and their spatial relativity are less influenced by human factors. The Cr, Cd has a medium degree of correlation and their distribution of As, Ni spatial relativity are common affected by natural factors and human beings. The content , Zn, Cd, Cu closely related to the distribution of industrial enterprises of the study area.