有机氯农药六六六污染土壤的植物修复研究

我国20世纪六七十年代大量施用的有机氯农药,由于其性质极其稳定,在土壤至今仍有残留。植物修复有机农药污染土壤并不多见,但具有广阔的应用前景。此项研究对提高土壤环境质量、保证农产品的安全、实现农业可持续发展等有着重要的理论和现实意义。文章以多花黑麦草(Lolium multiforum Lan.)、紫花苜蓿(Medicago sativa L.)和籽粒苋(Amaranthus hypochondriacus L.)作为供试植物,在有机氯农药六六六(HCH)质量分数为1.09 mg.kg-1的污染土壤中种植3个月,研究了种植不同植物条件下土壤中HCH的消解情况。研究结果表明,与对照相比,种植植物大大提高了土壤中微生物数量和酶的活性,并且微生物的数量和酶的活性与土壤中HCH的消解密切相关。试验结束后,不同处理中HCH及其4种异构体的总含量降低幅度为43.87%~65.79%,其中种植紫花苜蓿和多花黑麦草的处理中HCH消解较快,对HCH污染土壤修复的效果较好。可见,植物修复技术是一种可行的环境友好的修复六六六污染土壤的技术。

Phytoremediation of HCH-contaminated soils

In the sixties and seventies,hydrocarbon pesticides were widely used in China.Now,there are also residues in soils for the extreme solidity chemical character.It is rare that the phytoremediation of contaminated soil,but it has a good prospect of application and extension.Moreover,phytoremediation of contaminated has great theoretical and practical significance to improve environmental quality of soil,undertake for agriculture products security,and for the Sustainable Development of Agriculture.Lolium multiforum Lan,Medicago sativa L.and Amaranthus hypochondriacus L.were studied for rhizosphere characterization to optimize HCH phytoremediation.The concentration of HCH was 1.09 mg.kg-1 in soil.And three grasses were planted for three months in the CHC contaminated soil.The result showed that planting significantly increased soil microbial counts and enzyme activity.And bacterial counts and soil enzyme activity were closely related to HCH dissipation in soil.After the growth of the grasses 3 months,the concentration of HCH and the main degradation products in soil was decreased to 43.87%~65.79%.The dissipation rate of HCH was faster in the treatments planting Lolium multiforum Lan,Medicago sativa L.than planting Amaranthus hypochondriacus L.In short,phytoremediation technique is a possible and environmentally friendly technology for remediation HCH-contaminated soils.