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- 2018
河北省宣化地区原煤与燃煤污染及其生态环境效应评价
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Abstract:
摘要: 通过对河北省宣化原煤及燃煤污染区表土和近地降尘的野外调查和样品分析,查明了表土及降尘中Hg、Cd、V、Zn、Mo、U、Mn、Cr等13种重金属元素及16种多环芳烃(PAHs)的地球化学特征。结果表明,原煤区土壤以Hg、Cd污染为主,污染区在煤带两侧约100 m范围内,燃煤区土壤以Hg、Cd、V污染为主,污染范围在燃煤企业下风口超过2 km。原煤区表土中Hg、Cd、Zn、Mo、U及PAHs与燃煤区表土中Hg、V、Mo、U、Mn、Cr及PAHs主要通过大气沉降带入。区内土壤中脲酶、碱性磷酸酶及β-葡萄糖苷酶活性均受到不同程度抑制,其中以β-葡萄糖苷酶最为明显,且燃煤区较原煤区抑制更为显著,反映了煤污染对土壤碳循环过程影响较大。
Abstract: Geochemical distribution characteristics of 16 PAHs and 13 kinds of heavy metal elements,including Hg, Cd, V, Zn, Mn, Cr, Mo, U,etc., were investigated in the topsoil and near surface dust of the raw coal and coal combustion polluted area in Xuanhua, Hebei Province. The results showed that Hg and Cd are the dominant pollutant within about 100 meters in raw coal polluted area. While, Hg,V, and Cd were the dominant pollutants within 2, 000 meters in coal combustion area, where being downwind from coal burning enterprises. And the accumulation of Hg, Cd, Zn, Mo, U, PAHs in topsoil of the raw coal polluted area and Hg, V, Mo, U, Mn, Cr,PAHs of the coal combustion polluted area were mainly from atmospheric deposition. Enzyme activities of the urease, alkaline phosphatase and βglucosidase in the soil were all restrained to varying degrees with the greatest of βglucosidase in polluted areas. In addition, the inhibition of soil enzyme activities by coal combustion polluted is more significant than that of raw coal, implying the negative effect of coal pollution on soil carbon cycling