基于正态模糊数的区域土壤重金属污染综合评价

针对土壤重金属污染评价的不确定性,采用模糊数对其进行描述.在土壤重金属含量满足正态或对数正态分布检验基础上,构建了基于正态模糊数的区域土壤重金属污染综合评价方法.以江苏省T市为例进行评价方法实证分析,结果表明:除As出现轻度污染外,其他重金属含量均处于清洁水平,其中Hg、Cu、Zn处于局部轻度污染状态,各重金属富集污染程度排序为:As ＞Cu＞ Hg＞ Zn＞ Ni＞ Cr＞ Cd＞ Pb,研究区土壤重金属污染综合评价为清洁水平,As、Hg、Cu 、Zn应该作为相关部门污染控制的重点对象.与传统的三角模糊数方法的评价结果相比,该方法能更为精确的描述不同重金属含量的隶属度大小,评价结果所包含的信息更为全面、准确.

An integrated assessment for regional heavy metal contamination in soil based on normal fuzzy number

Due to the uncertainty of assessment of heavy metal contaminations in soils, an integrated approach for evaluation of heavy metals contamination in regional soil based on normal fuzzy number was established. This evaluation method was applied to evaluate the soil contamination of heavy metals in T City of Jiangsu Province. The result showed that most of heavy metals were at clean level except As at slight contamination level. Hg, Cu, Zn were also at slight contamination level in parts of the study area. Enrichment contamination degree of heavy metal was in the order of As>Cu>Hg>Zn>Ni>Cr>Cd>Pb. Although most of heavy metals was at clean level, As, Hg, Cu, Zn were in the edge of contamination level and much attention should be paid on controlling those elements. Compared with the result of triangular fuzzy number method, this method described the membership degree of each heavy metal more precisely and provided more comprehensive and accurate evaluation information.