中山市工业园周边土壤重金属污染及风险评估

Pollution and Ecological Risk Assessment of Heavy Metals in the Surrounding Soil of Industrial Park in Zhongshan City

重金属富积程度及生态危害是土壤重金属污染研究的重要指标,为了能更准确及客观地反映中山市土壤重金属污染情况,文中以中山市主要工业园区周边土壤为研究对象,收集最新的广东省土壤背景值中位值及珠三角经济区土壤风险评估筛选值,分析了土壤中铬、镉、铜、镍、锌5种重金属的含量及污染特性、相关性及潜在生态危害。结果显示,中山市主要工业园区周边土壤重金属污染程度为轻污染,5种金属除铬未现超标外,其余均出现超标,超标率由高到低顺序:镉>镍>铜>锌>铬;人为活动引起五种重金属污染程度处于清洁至偏重度水平,重金属富集程度由强到弱顺序:镉>铜>镍>锌>铬;5种重金属中铬与铜、镉与镍具有显著相关性;工业园区周边土壤重金属生态危害处于轻微到中度危害水平,56%土壤样品为轻微危害水平,44%土壤样品处于中等危害水平,重金属潜在生态危害由强到弱顺序:镉>铜>镍>铬>锌。

The purpose of this study was to analyze the contents and pollution characteristics of five heavy metals （chromium, cadmium, copper, nickel, and zinc） in the soil surrounding of the main industrial parks in Zhongshan City with the new standard value. Nemero-index, Geo-accumulation-index, Pearson, Hakanson potential ecological risk index were used to assess the pollution and ecological risk of heavy metals in these soils. The experimental results showed that the surrounding soil in industrial parks has light heavy metal pollution, just only Cr did not exceed the standard, the ex- ceeded rate was the following order.. Cd 〉 Ni 〉 Cu 〉Zn 〉Cr. Geo-accumulation index indicated that the pollution degree of these metals ranged from heavy to light is ： Cd 〉Ni 〉 Cu〉 Zn 〉 Cr. The significant correlation was presented between Cr and Cu, Cd and Ni. In the present work, the ecological risk of heavy metals was in the following order： Cd〉 Cu 〉 Ni 〉 Cr 〉 Zn. The ecological risks of heavy metals in these soils from light to moderate risk level is that, more than 56% of the samples are in the light risk level, more than 44% of the samples are in the moderate risk level.