【摘要】 人类活动方式与重金属污染程度和空间分布密切相关.为评价河口冲积岛屿土壤重金属污染的空间特征及风险水平,本研究以上海市崇明岛为例,基于135个土壤表层样本的9种重金属(Cu、Cr、Ni、Zn、Pb、Cd、As、Hg和Mn)的浓度数据,结合污染风险指数和空间分析方法开展了相关研究.研究结果显示9种土壤重金属浓度均值都超过其当地的土壤背景值,表明研究区土壤均受到了不同程度人为活动的影响.空间分析结果显示所有重金属的污染热点主要集中在岛屿边缘附近,这可能是由于研究区人工围垦的外围土壤形成较晚,易受到人类活动的干扰以及上游冲积泥沙的影响.污染风险评价结果表明,研究区土壤重金属污染总体呈"轻度污染"风险水平,均未达到"极高风险"等级.研究结果可为河口岛屿重金属污染预防和控制提供科学依据.更多还原

【Abstract】 The human activities are closely related to the degree and spatial distribution of heavy metal(HM) pollution. To evaluate the pollution level of HMs in soils of estuary alluvial island, the nine HM concentrations(including Cu, Cr, Ni, Zn, Pb, Cd, As, Hg and Mn) of 135 soil surface samples were investigated in Chongming island, Shanghai. Then, the pollution characteristics and risk assessment were performed by using pollution risk indices and spatial analysis methods. The results showed that the mean concentrations of the nine HMs in soils were more than their corresponding background value, indicating that the soils were affected by human activities. Spatial analysis indicated that the HM pollution was mainly concentrated near the edge of the island. This may be due to the late formation of the surrounding reclamation soil, which is susceptible to the human activities and upstream alluvial sediment. The results of pollution risk assessment revealed that the soil environmental quality in the study area generally presented a “slight pollution” risk and none of them has reached the level of “very high risk”. Our findings can provide scientific basis for the prevention and control of heavy metal pollution in estuary islands.更多还原