基于污染损失率法的土壤重金属污染评价——以开封市化肥河污灌区为例

Pollution Assessment of Soil Heavy Metals Based on Pollution Lost Rate Method:a Case Study of the Huafei River Sewage Irrigated Region,Kaifeng

以开封市化肥河污灌区为例,应用污染损失率法开展了土壤环境质量评价.结果表明,污灌区大部分样点土壤Cd和As的单项污染损失率明显高于其他重金属,对综合污染损失率的贡献大.各重金属单项污染损失率的大小顺序为Cd>As>Zn>Cr>Pb>Cu.从各样点重金属综合污染损失率来看,大部分样点属于中度污染(Ⅳ级),占总样点数的76.93%;样点No.13和No.12属于重度污染(Ⅴ级);样点No.1属于轻度污染(Ⅲ级).污染损失率法与综合污染指数法的评价结果基本一致,前者对样本中超标较严重的污染因子有更强的分辨率.

Taking Huafei River sewage irrigated area in Kaifeng as an example, pollution lost rate method was applied to pollution assessment of soil heavy metals. The results showed that the single pollution lost rate of the soil heavy metals was in the order of Cd〉As〉Zn〉Cr〉Pb〉Cu, and the single pollution lost rates of Cd and As are higher than that of other metals, so the integrated pollution lost rate of the metals in any sample site is contributed by them. From the comprehensive pollution lost rate, most sample sites reached the intermediate level （IV level）, and accounted for 76.93% of the total sample sites. The sample sites of No. 13 and No. 12 reached the heavy level （V level）, accounted for 15.38%, and No. 1 reached the light level （III level）, accounted for 7.69% of the total sample sites. The Nemerow integrated factor indexes of the soil samples were also calculated. As a result, the assessment conclusions by the two methods were almost consistent, and the pollution lost rate method manifested more resolving power in the serious pollution index of the soil.