云南某些地区土壤中六六六和DDT残留的研究

本文应用气相色谱法测定施用过农药的森林、苗圃、果园和农田土壤及其附近水体中六六六和DDT的残留量。研究指出,残留量和施药量成正相关,在施用农药较多的地方六六六和DDT的残留量相当高。六六六的各种异构体在土壤中的分解速度不同:丙体分解最快,其次是甲体,丁体和乙体分解缓慢,如果用丙体六六六代替工业六六六作杀虫剂,可以使土壤中的残留量降低90％。本文也表明,农药在土壤中的残留量因施用方法而异。

OBSERVATION ON RESIDUAL EFFECTS OF BHC AND DDT IN SOME TYPES OF SOIL IN YUNNAN PROVINCE

Soil and water samples were collected from forest stands, tree nurserics,orchards and crop fields in different parts of Yunnan from 1975 to 1976. Gaschromatography analysis was used to detect the residues of BHC and DDTwhich had been frequently applied in these soils.It was found that there wasa positive correlation between the quantity of pesticide used and that of theresidue. Residue accumulated most in areas where the pesticide was used mostintensively. Speed of degradation in soil varies among different isomers of BHC:γ-BHCis the fastest,α-BHC intermediate,and δ-BHC and B-BHC the slowest. If γ-BHC is used as a pesticide to replace the industrial BHC,residue insoil would be reduced by 90%. Residue of pesticides varied with met-hods of application.