Biodegradation of imazapyr in typical soils in Zhejiang Province, China

编号 zgly0000372465

文献类型 期刊论文

文献题名 Biodegradation of imazapyr in typical soils in Zhejiang Province, China

作者 WANGXue-dong  ZHOUSu-mei  WANGHui-li  FANDe-fang 

作者单位 KeyLaboratoyofPesticideandChemicalBiology-MinistryofEducation  CollegeofAgronomy  PesticidesandEnvironmentalToxicologyResearchInstitute 

母体文献 Journal of Environmental Sciences;环境科学学报: 英文版 

年卷期 2005,17(4)

页码 593-597

年份 2005 

分类号 X53  S482.3 

关键词 生物降解  贫瘠土壤  浙江  有机杀虫剂  环境污染 

文摘内容 The degradation of imazapyr in non-sterile and sterile soils from four sampling sites in Zhejiang, China was studied. The results showed that the half-lives of imazapyr in non-sterile soils were in the range of 30 to 45 d, while 81 to 133 d in sterile( by autoclaving) soils. It means the rate constants of imazapyr under non-sterile conditions were 2.3--4.4 times faster than that under sterile(by autoclaving)conditions, evidently indicating that the indigenous microorganisms in soil play an important role in the degradation of imazapyr. The different sterilization methods could result in different degradation rates of imazapyr. The heat of sterilization of soil largely decreased the degradation. However, the sterile treatment of soil by sodium azide had a different effect from that by autoclaving. Further more, the mechanism was also discussed. Biodegradation in four non-sterile soils accounted for 62% to 78% of imazapyr degradation. In contrast, less than 39% of imazapyr degradation was associated with chemical mechanisms. Therefore, the degradation mechanism was predominantly involved in biology including organisms and microorganisms in soil. Two imazapyr-degrading bacterial strains were isolated in enrichment culture technique and they were identified as Pseudomonas fluorescenes biotype [[ ( ZJX-5 ) and Bacillus cereus (ZJX-9),respectively. When added at a concentration of 50μg/g in mineral salts medium(MSM), ZJX-5 and ZJX-9 could degrade 81% and 87% imazapyr after 48h of incubation. For the treatment of incorporation of ZJX-5 or ZJX-9 into soil, the degradation rate enhanced 3-4 fold faster than that for control samples, which showed an important value in quick decontamination of imazapyr in soil。