作 者: ; ; ; ; ; ; ; ; ; (张文具); (秦宝平);
机构地区: 北京大学城市与环境学院地表过程分析与模拟教育部重点实验室
出 处: 《环境科学学报》 2003年第4期447-451,共5页
摘 要: 采集了覆盖整个天津地区的 188个土壤表层样品 ,并分析了样品中p ,p′ DDE ,p ,p′ DDD ,p ,p′ DDT ,o ,p′ DDE ,o ,p′ DDD和o ,p′ DDT等 6种DDT代谢产物 .结果表明p ,p′ DDT和p ,p′ DDE是表土中的主要污染物 ,其平均残留量分别为 2 7 5和 18 8ng·g-1.不同类型土壤∑DDT差异不显著 .污灌区与非污灌区内的样品中DDT及其代谢产物的差异不显著 ,但1970— 1980年DDT施用量较高的地区如今土壤中的残留量均较高 .土壤理化性质如pH以及TOC对DDTs的残留量有较显著的影响 .禁用 2 0年以来 ,DDT的总体残留量水平仍较高 ,是否依然有间或使用 。 samples of surface soil were collected from the Tianjin area to study the contamination of DDT and its metabolites. For all samples, p,p′ DDE, p,p′ DDD, p,p′ DDT, o,p′ DDE, o,p′ DDD and o,p′ DDT were analyzed. p,p′ DDT and p,p′ DDE were the main contaminant compounds in the surface soil samples with mean concentrations of 27\^5 and 18\^8 ng g -1 , respectively. No significant differences in residues of DDTs were found between the soils from wastewater irrigated area and other areas. The wastewater irrigation was not an important source of DDTs in the area. The spatial distribution of soil DDTs in the area did correlate well with the application rates of pesticides. In addition, both pH level and organic carbon content were also known factors affecting the levels of DDT and its metabolites. Although it was assumed that the use of these chemicals was banned in the early 1980;s, the current concentration levels appear to be too high to be merely residuals after 20 year;s degradation.
领 域: [环境科学与工程]