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通过检测重庆市长江沿岸表层土壤(0-5 cm)和深层土壤(0-20 cm)中六六六和滴滴涕的含量发现,表层土壤中总六六六(包括α-六六六、β-六六六、γ-六六六、δ-六六六)和总滴滴涕(包括p,p'-DDE、p,p'-DDD、o,p'-DDT、p,p'-DDT)含量范围为0.185-1.374 ng/g和0.807-38.281 ng/g,分别对应深层的总六六六含量0.079 5-1.692 ng/g和总滴滴涕含量0.308-88.306 ng/g.研究区内有机氯农药在土壤中的垂直分布反应了滴滴涕残留是"老"的来源,并证实了林丹的使用对该区域的有机氯农药污染有一定的影响.Abstract: Concentrations of hexachlorocyclohexane(HCH)and dichlorodiphenyltrichloroethane(DDT)were determined in shallow subsurface(0~5 cm depth)and deep soil layers(5~20 cm depth)from the agricultural soils along the Yangtze River in Chongqing,China.Concentrations of total HCHs(including α-HCH,β-HCH,γ-HCH and δ-HCH)and total DDTs(including p,p'-DDE,p,p'-DDD,o,p'-DDT and p,p'-DDT)in shallow subsurface soils ranged from 0.185 to 1.374 ng/g,averaging 0.479 ng/g,and from 0.807 ng/g to 38.281 ng/g,averaging 7.274 ng/g,respectively,and those in the deeper layers ranged from 0.079 5 to 1.692 ng/g,averaging 0.564 ng/g,and from 0.308 to 88.306 ng/g,averaging 13.718 ng/g,respectively.The vertical distribution of HCHs and DDTs suggested that DDT residues resulted from"old"sources and that the contamination of HCHs in this region was partially attributed to the local use of lindane. 相似文献
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[目的]研究矿区土壤铜、铅和锌的形态分布及生物活性。[方法]选取广东某金属硫化物矿区外围2个代表性的农田深层土壤样品,运用Tessier连续提取法分析其铜、铅和锌的总量和5种化学形态。[结果]结果表明,土壤中铜、铅和锌主要以残渣态形式存在,铁锰氧化物结合态和有机物结合态次之,碳酸盐结合态很少,可交换态最低。不同元素在不同土壤类型和不同土壤层位的形态分布有很大差别。以生物活性系数来评价重金属的危害性,这3种元素的生物活性均偏低,其中铅〉锌〉铜,生物可利用性不高,对生态环境的潜在危害性不大。[结论]该研究结果对土壤铜、铅和锌的环境生物效应及其迁移转化规律具有重要意义。 相似文献
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