垃圾填埋场及周边土壤重金属污染研究

Research on the Heavy Metal Pollution of Soil in and Around Landfill

采集内江市高桥垃圾填埋场内和周围土壤样品,分析其基本性质和重金属含量,评价重金属污染程度和潜在生态风险。结果表明,填埋场内外土壤发生酸化,有机质含量升高,土壤铁含量下降,Mn含量升高;土壤重金属综合污染为轻度,潜在生态风险除渗滤液污染土壤较重外,其他均为中度;其中Cd的污染贡献最大,研究区域土壤Cd含量均超过土壤环境质量三级标准,渗滤液污染进一步加剧其污染程度;Hg、Cu和Zn虽然超过土壤环境质量三级标准,但垃圾填埋极大的提高了其生态风险,且填埋场外围土壤Hg和Cu已受到影响,需要提高警惕,关注其后续变化,降低其环境和生态危害。

The soil samples were collected in and around the Neijiang Gaoqiao landfill. The basic properties and heavy metal contents were analyzed, and the heavy metal pollution levels and potential ecological risk were also evaluated. The results showed that the soil had become acidified, the contents of the organic matter and Mn increased, but the contents of Fe decreased. The comprehensive heavy metals pollution of soil was mild, and other potential ecological risks were moderate, except the leachate pollution of soil was heavy. Among them, Cd had created biggest pollution because its contents of all the soil samples in research area had exceeded the third - level limits of the national soil quality standard, and the leachate had further increased its pollution level. The contents of Hg, Cu and Zn had not exceeded the third - level limits of the national soil quality standard, but the landfill had greatly improved its ecological risk. Moreover, the soil around the landfill had been affected by Hg and Cu. Thus, be on the alert and pay close attention to its subsequent variations was necessary in order to reduce its environmental and ecological damage.