微氧环境氯代烃生物降解的研究现状与展望

The current status and prospects of biodegradation of chlorinated hydrocarbons under micro-aerobic conditions

总结了微氧环境的生物氧化特性,系统调研了微氧环境中氯代烃(CAHs)的污染情况,发现地下水,土壤包气带,河床沉积物和垃圾填埋场等微氧环境场地存在广泛的CAHs污染.此外,研究归纳了氧调控下的CAHs降解途径,系统分析了微氧环境CAHs的转化特性、微生物活性及功能基因表达特征.总结发现微氧条件下氧对CAHs降解有5方面影响,CAHs降解速率甚至比好/厌氧条件下更高;微氧环境中好氧和厌氧降解菌能同时存在,多种微氧环境污染场地能同时检测到好氧功能基因(etnC和etnE)和厌氧功能基因(vcrA和bvcA),进一步表明好氧转化和厌氧脱氯能在同一时空发生.最后从监测装置开发、适应机制、转化机制和微生态演变规律4方面展望了未来的发展方向,结果为微氧环境的污染物转化研究及污染控制策略的制定提供了方向.

The biodegradation characteristics of chlorinated hydrocarbons(CAHs)in micro-aerobic environments were summarized in this study.A systematic investigation of CAHs contamination in micro-aerobic environments was conducted,revealing extensive CAHs pollution in locations such as groundwater,soil vadose zones,riverbed sediments,and landfill sites with micro-aerobic conditions.Additionally,the study compiled the pathways of CAHs degradation under oxygen regulation and analyzed the transformation characteristics,microbial activity,and functional gene expression of CAHs in micro-aerobic environments.It was concluded that oxygen had five distinct effects on CAHs degradation under micro-aerobic conditions,with degradation rates often surpassing those observed under strictly aerobic or anaerobic conditions.Moreover,both aerobic and anaerobic degraders coexisted in micro-aerobic environments,as evidenced by the detection of aerobic functional genes(etnC and etnE)and anaerobic functional genes(vcrA and bvcA)in various micro-aerobic pollution sites,indicating that aerobic transformations and anaerobic dechlorination could occur simultaneously in the same spatial and temporal settings.Finally,future development directions were projected in four aspects,including monitoring device development,adaptation mechanisms,transformation mechanisms,and microecological evolution patterns.These results offer valuable insights for the study of pollutant transformation in micro-aerobic environments and the formulation of pollution control strategies.