海南省琼中农产品产地土壤重金属污染普查分析

Analysis of Soil Heavy Metal Pollution Investigation in Agricultural Producing Areas of Qiongzhong, Hainan

摘要: 采用内梅罗污染指数法、地积累污染指数法和潜在生态危害指数法等3种方法，对海南省中部的琼中农产品产地土壤的5种重金属Cr (铬)、Pb (铅)、Cd (镉)、As (砷)、Hg (汞)的普查样品含量及其相关性进行分析，并对重金属污染程度及土壤环境质量现状进行评估。结果表明：30个样品的重金属Cr、Pb、Cd、As和Hg平均含量分别为39.26 mg/kg、30.89 mg/kg、0.08 mg/kg、2.49 mg/kg和0.04 mg/kg；Pb与Cd含量之间的相关系数0.60，其次，Hg与Cd之间的相关系数0.26，其余的相关系数很小；以海南省表层土壤背景值为标准，重金属的内梅罗单项污染指数均 ≤ 20.34，污染率均在50%以上，内梅罗综合污染指数为2.23，污染等级为中度污染，4级；以国家环境质量二级评价标准，内梅罗单项污染指数均 ≤0.8，污染率3%，内梅罗综合污染指数为0.22，污染等级为清洁，1级；Pb的地积累污染指数为0.04，属于无污染~中污染，其余的Cr、Cd、As、Hg地积累污染指数 < 0，属于无污染状态；琼中土壤重金属潜在生态危害指数为138.21，整体上表现为轻微生态危害。

Abstract: The contents and correlation of soil heavy metals, including Cr (chromium), Pb (lead), Cd (cadmium), As (arsenic) and Hg (mercury) in Qiongzhong the agroproducing areas in the middle of Hainan province, were analyzed. The environmental qualities of soil heavy metal pollution were evaluated by using 3 methods of Nemero pollution index, geoaccumulation pollution index and potential ecological hazard index. The results showed that the average contents of 30 samples of Cr, Pb, Cd, As and Hg were 39.26 mg/kg, 30.89 mg/kg, 0.08 mg/kg, 2.49 mg/kg and 0.04 mg/kg, respectively. The correlation coefficient between Pb and Cd in contents was 0.6, and secondly, the correlation coefficient between Hg and Cd in contents was 0.26. And there was little correlation among the rest of soil heavy metals. Taking the background value of surface soil in Hainan as the reference standard, the Nemero single factor pollution index was less than or equal to 20.34, the pollution rate was above 50%, and the Nemero complex pollution index was 2.23, which showed the fourth class be-longing to moderate pollution level. Taking the background value of the secondary standard of na-tional soil environmental quality as the reference standard, the Nemero single factor pollution index was less than or equal to 0.8, the pollution rate was 3%, and the Nemero complex pollution in-dex was 0.22, which showed the first class belonging to clean level. The geoaccumulation pollution index of Pb was 0.04, which belonged to the non to moderate pollution level, and the geoaccumulation pollution index of Cr, Cd, As and Hg was less than 0, which belonged to the non pollution level. The potential ecological hazard index of soil heavy metals in Qiongzhong soil was 138.21, which be-longed to light ecological hazard on the whole.