山东烟台南部海岸带地区土壤重金属来源、空间分布及潜在风险评价

Assessment of Sources Spatial Distribution and Ecological Risk of Heavy Metals in Soils in the Southern Coastal Zone of Yantai City in Shandong Province

海岸带处于陆地和海洋的接合部,人类开发活动密集,环境影响因素日趋复杂。选取烟台南部海岸带为研究对象,系统采集686个表层土壤样品对As,Cd,Cr,Cu,Hg,Ni,Pb,Zn共8个重金属元素含量进行测量,采用多元统计法及地统计法分析了8个重金属元素的来源及分布特征。最后对烟台南部海岸带地区进行了潜在生态风险评价。研究结果表明烟台南部海岸带地区整体污染程度较轻,所有重金属元素含量平均值均未超过国家二级标准。其中Cr,Ni,Cu元素主要来源于成土母质;As,Pb为混合源;Cd,Zn主要来自于工业三废、农业生产。研究区整体处于中低生态风险水平,Cd,Hg元素高生态风险点数量较多,需优先治理。

The coastal zone is located at the junction of land and sea. The intensive developing human activities makes the environment change more and more complicated. Choosing southern coastal zone in Yantai city as the study area, selecting 686 surface soil samples, the contents of 8 heavy metals, such as As, Cd, Cr, Cu,Hg, Ni, Pb and Zn have been measured. The source and distribution characteristics of eight heavy metal elements have been analyzed by using multivariate statistical method and geostatistics. The ecological risk assessment of the southern coast in Yantai city has been carried out. It is showed that the overall pollution in the southern coastal zone in Yantai city is relatively clear, and the average of all heavy metal elements does not exceed the national second-class standard. The elements Cr, Ni and Cu are mainly derived from parent materials, As, Pb are mixed sources, Cd, Zn is mainly from the industrial waste and agricultural production. The study area is at a low ecological risk level as a whole, and Cd and Hg elements have a high ecological risk point and need to be given priority in management.