吉林省红旗岭和漂河川镍矿区耕地土壤重金属污染特征

Characteristics of Heavy Metal Pollution in Farmland Soil of the Two Nickel Mines of Hongqiling and Piaohechuan,Jilin Province

土壤中重金属是一种潜在的污染物,其长期性、隐蔽性、不可逆性导致土壤重金属污染难以消除和修复治理,而矿山开采和冶炼可对矿区土壤造成不同程度的重金属污染。为了明确吉林镍矿区耕地土壤重金属（Cu、Zn、Ni、Cr、Pb、Cd）的污染程度,通过对吉林省红旗岭和漂河川镍矿区土壤样品采集和重金属含量测定,采用单因子污染指数法、综合污染指数法和潜在生态危害指数法对镍矿区土壤重金属污染程度进行了评价。结果表明：吉林省红旗岭和漂河川镍矿区耕地土壤重金属Cu、Zn、Ni、Cr、Pb和Cd的含量分别为12.26~195.70,70.50~116.50,16.76~650.30,0.33~60.55,10.72~103.40,0.01~0.37 mg/kg,平均含量分别为48.39,91.06,93.71,9.71,26.04,0.11 mg/kg;与吉林省土壤背景值相比,Cu、Zn、Ni、Cd的平均含量均高于吉林省土壤背景值,分别为背景值的2.83,1.13,4.38,1.10倍,其余重金属平均含量低于吉林省土壤背景值。内梅罗综合污染指数评价结果表明,研究区50%的采样点为安全或警戒级,30%的采样点为轻污染,7.5%的采样点为中污染,12.5%的采样点为重污染。潜在生态危害指数法评价结果表明,研究区内土壤重金属潜在生态危害等级均为轻微。这说明吉林省红旗岭和漂河川镍矿区耕地土壤受到重金属的潜在环境污染效应较小。

Heavy metals are a kind of potential pollutants in soils, which are difficult to remove, re- pair and harness because of their characteristics of long term, concealment and irreversibility, more- over, the mining and smelting can cause different degrees of heavy metal pollution in mining soil. In order to clear the degree of heavy metal contamination in farmland soil of Jilin nickel mine area, soil samples in the two nickel mines of Hongqiling and Piaohechuan were collected for analyzing the con- tents of Cu, Zn, Ni, Cr, Pb and Cd. Meanwhile, cal pollution index method and potential ecological single factor pollution index, Nemerow Syntheti- risk index were used to evaluate pollution degree of heavy metals in the nickel mine area. The results show that the contents of Cu, Zn, Ni, Cr, Pb and Cd were in the range of 12.26--195.7, 70.50--116.5, 16.76--650.3, 0.33--60.55, 10. 72--103.4 and 0. 01--0. 37 mg/kg, and the average contents were 48.39, 91.06, 93.71, 9.71, 26. 04 and 0. 11 mg/kg, respectively, in the farmland soil of the two nickel mines of Hongqiling and Piaohechuan, Jilin province. The average contents of 4 kinds of heavy metals, i.e Cu, Zn, Ni and Cd, were 2. 83, 1.13, 4.38 and 1.10 times higher than the soil background value in Jilin province, respectively ; However, that of the others was all lower than the background value. The evaluation result from Nemero comprehensive pollution index showed that among the total sam- piing sites in the study area, 50% was at the level of safety or warning, 30% was at slight level, 7.5% was at moderate level, and 12. 5% was at heavy level. The evaluation result from the potential ecological risk index showed that the potential ecological hazard of heavy metals in the study area soil was all of the slight class. Therefore, the potential environmental pollution effects of heavy metals on the cultivated soil in the nickel mining area of Hongqiling and Piaohechuan of Jilin province were not significant.