南京地区土壤中有机氯农药残留及其分布特征

Residues and distribution character of organochlorine pesticides in soils in Nanjing area

在 2 0 0 2年 4月— 2 0 0 3年 10月间 ,以网格法在农田土壤内均匀布点 ,另选择典型林地、闲置地及工业区土地采样 ,对南京地区土壤中有机氯农药残留及分布状况进行了研究 ,侧重探讨有机氯在不同利用类型土壤中的残留量、残留物的组成和分布状况 .研究结果表明 ,试区土壤HCHs和DDTs的检出率均高达 10 0 % ,残留范围分别为 2 7～ 13 0 6和 6 3～ 10 5 0 7μg·kg- 1 ,其中 >65 %的样点土壤有机氯残留总量低于 60 μg·kg- 1 .OCPs主要残留物为p,p’_DDE ,占残留总量的 80 %以上 .工业用地土壤中有机氯农药残留量明显低于农业土壤 ,不同利用类型土壤中有机氯残留总量排序为 :露天蔬菜地 >大棚蔬菜地 >闲置地 >旱地 >工业区土地 >水稻土 >林地 .与国内同类最新报道相比 ,南京地区土壤中OCPs的残留较低 ;而与国外相应值比较 ,南京地区土壤中OCPs残留量高于德国 。

Soil samples of arable land, woodland, unused land and industrial land were collected in April 2002 and October 2003 respectively. The residues and distribution character of organochlorine pesticides in the soils were measured by gas chromatography. HCHs and DDTs were found widely in all samples and with a range of 2.7～130.6 and 6.3～1050.7μg·kg^(-1) respectively. More than 65 percent of samples had a total residue of less than 60μg·kg^(-1). And the p,p'-DDE, which was the main components in residues of organochlorine pesticides, took over 80% of the total, indicated that the residues in soils were from historical use. The residues in industry area were lower than those in agricultural soils, exception of rice fields. The residue level in different lands was in the order as follows: open vegetable land>greenhouse vegetable land > wasteland >dry land>industry land>paddy field>woodland. Compared to the reference data, the pollution burden in soils of Nanjing was lower than those in other areas of China and in Argentina and Poland, but higher than those in German.