大伙房水库土壤汞动态与污染特征研究

Abstract

为了解大伙房水库汞污染现状和环境风险，选择10个采样点，采集了30个土壤样品，20个水体样品，30个空气样品，分析不同区域土壤、水体和大气中的总汞含量及分布，并采用地累积指数法和潜在生态风险指数法对比探讨了土壤总汞污染现状和环境风险，分析其生物可利用性及其潜在风险，探究大气汞与土壤汞富集的关系。结果表明，大伙房水库土壤中的汞平均含量分别为27.76 μg/kg，变异系数为69.32，最大值为82.47 μg/kg，最小值为12.49 μg/kg；大伙房水库采集水中的汞平均含量分别为19.87 μg/kg，变异系数为71.35，最大值为53.82 μg/kg，最小值为2.92 μg/kg。向大气释放汞的年排放通量17.80~62.47 μg/m2/h，平均37.76 μg/m2/h。土壤汞含量与大气汞浓度的相关系数为0.81** (P < 0.01)，相关显著，土壤汞富集对大气汞污染的贡献较大。从汞的空间分布表明，社河流域汞金属污染较低，浑河苏子河流域沉积物汞金属含量较高，水中汞含量较低。地累积指数的土壤汞污染评价和潜在生态危害指数的土壤汞生态风险评价，两种评价结果表明大伙房水库污染水平和生态风险都较低，大气汞污染对土壤汞富集的贡献较大。 To explore the pollution situation and the environmental risk of mercury in Dahuofang reservoir, we choose 10 sampling points, collected 30 soil samples, 20 water samples and 30 air samples to analyze the contents and distribution of mercury in soil, water and air in different areas. We discuss the pollution status and environmental risks of mercury in soil, analyze the biological availability and potential risks and explore the relationship between the atmospheric mercury and the soil mercury enrichment by the geoaccumulation index method and potential ecological risk index method. The results indicated that the average content of mercury in the soil of Dahuofang reser-voir were 27.76 μg/kg, the variation coefficient was 69.32, The maximum was 82.47 μg/kg, the minimum was 12.49 μg/kg; The average content of mercury in the collected water of Dahuofang reservoir were 19.87 μg/kg, The variation coefficient was 71.35, the maximum was 53.82 μg/kg, the minimum was 2.92 μg/kg. The released mercury flux into the atmosphere was 17.80 - 62.47 μg/m2/h, the average was 37.76 μg/m2/h. The correlation coefficient between mercury content in soil and the mercury concentration in atmospheric was 0.81** (P < 0.01), they were significantly correlated. The soil mercury enrichment contributed greatly to atmospheric mercury pollution. According to the spatial distribution of mercury, it indicated that the river was slightly polluted. The mercury content in sediment of Hun River and Suzi River was higher, and the content of mer-cury in water was lower. The evaluation of soil mercury pollution by geoaccumulation index method and the soil mercury ecological risk assessment by potential ecological risk index method. The results showed that the pollution level and the ecological risk of Dahuofang reservoir were low, atmospheric mercury pollution contributed great to soil mercury enrichment.