Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou, 221116, Jiangsu Province, China; Jiangsu key laboratory of resouces and environmental information engineering, Xuzhou, 221116, Jiangsu Province, China; School of Environment Science and Spatial Information, China University of Mining and Technology, Xuzhou, 221116, China.
Engineering Research Center of Ministry of Education for Mine Ecological Restoration, China University of Mining and Technology, Xuzhou, 221116, Jiangsu Province, China; Jiangsu key laboratory of resouces and environmental information engineering, Xuzhou, 221116, Jiangsu Province, China; School of Environment Science and Spatial Information, China University of Mining and Technology, Xuzhou, 221116, China.
J Hazard Mater. 2020 Apr 5;387:121666. doi: 10.1016/j.jhazmat.2019.121666. Epub 2019 Nov 11.
Mining activities are considered the most important factor causing heavy metal accumulation in surface soil and it is important to understand the spatial distribution and source of heavy metals in typical steppes. In this study, the contents, spatial distribution, and sources of heavy metals were determined using geostatistical analyses, multivariate statistical analyses, and a positive matrix factorization (PMF) model using 152 soil samples collected from a grassland near the Sheng-Li coal base. The results shows that the mean concentration of heavy metals is low and does not threaten the quality of the local soil. However, the concentrations of eight heavy metals (Cu 15.04 mg kg, Zn 49.30 mg kg, Cd 0.11 mg kg, Pb 20.00 mg kg, Se 0.12 mg kg, Ge 1.45 mg kg, As 9.06 mg kg, and Sn 2.52 mg kg) are higher than their mean background values in soil in Inner Mongolia. High coefficients of variation for the heavy metals, especially Ge (1.03), and As (0.56), indicate that the concentrations of the elements are affected by the presence of the open-pit mines. Multivariate statistical and geo-statistical analyses show that Ge and As are highly correlated (R = 0.67, P < 0.01), suggesting that they have the same source. Using geostatistical and PMF models, we identified five potential pollution sources in the study area: 1) Industrial pollution (21.2 %), which includes smelting activity and open-pit coal mines, as suggested by elevated levels of Zn, Cd, Ge, and Cu; 2) Germanium mining (7.6 %), as indicated by higher levels of Ge and As; 3) Natural sources (37.2 %), as indicated by higher levels of Mn and Ni; 4) Coal mining activity (8.5 %), as indicated by higher levels of Sn and Cr; 5) Coal conveyor belts and high vehicular traffic, as indicated by elevated levels of Pb and Se. Taken together, the results of this study indicate that the coal base has a significant effect on the heavy metal concentration in the grassland. Therefore, the identification of the spatial distribution of heavy metals in the area may be key to controlling the pollution in the grassland. The results of this study can help to reduce pollution sources, cut down on pollution transport. So that zonal pollution control and ecological protection in the typical steppe region is achieved.
采矿活动被认为是导致表层土壤中重金属积累的最重要因素，因此了解典型草原中重金属的空间分布和来源非常重要。本研究采用地统计学分析、多元统计分析和正定矩阵因子（PMF）模型，对来自胜利煤田附近草原的 152 个土壤样本中的重金属含量、空间分布和来源进行了研究。结果表明，重金属的平均浓度较低，不会威胁当地土壤的质量。然而，八种重金属（Cu 15.04 mg/kg、Zn 49.30 mg/kg、Cd 0.11 mg/kg、Pb 20.00 mg/kg、Se 0.12 mg/kg、Ge 1.45 mg/kg、As 9.06 mg/kg 和 Sn 2.52 mg/kg）的浓度高于内蒙古土壤的平均背景值。重金属的高变异系数，特别是 Ge（1.03）和 As（0.56），表明这些元素的浓度受到露天矿的影响。多元统计和地统计学分析表明，Ge 和 As 高度相关（R=0.67，P<0.01），表明它们具有相同的来源。利用地统计学和 PMF 模型，我们在研究区域内识别出了五个潜在的污染源：1）工业污染（21.2%），这是由 Zn、Cd、Ge 和 Cu 的含量升高引起的，包括冶炼活动和露天煤矿；2）锗矿开采（7.6%），这是由 Ge 和 As 含量升高引起的；3）自然源（37.2%），这是由 Mn 和 Ni 含量升高引起的；4）煤炭开采活动（8.5%），这是由 Sn 和 Cr 含量升高引起的；5）煤炭输送带和高交通量，这是由 Pb 和 Se 含量升高引起的。综上所述，本研究结果表明，煤田对草原重金属浓度有显著影响。因此，识别该区域重金属的空间分布可能是控制草原污染的关键。本研究的结果有助于减少污染源，减少污染传输，从而实现典型草原区域的分区污染控制和生态保护。
