植物根际降解土壤多氯联苯机理研究进展

Research Progress on the Mechanism of Plant Rhizosphere Degradation of Soil Polychlorinated Biphenyls

多氯联苯(PCBs)是一类危害巨大的持久性有机污染物,由于19世纪以来各国工业制造行业的广泛生产和使用,大量PCBs经各种途径进入土壤环境中。土壤PCBs污染问题逐步成为威胁当代人类生命安全和制约社会快速发展的首要问题之一。进入21世纪后,植物修复技术由于其绿色、经济等理念,逐渐成为土壤PCBs污染修复领域的研究热点。诸多研究也证实了植物修复对PCBs污染土壤的修复作用,但鲜有相关文献论述植物根系在植物修复PCBs污染领域的巨大意义及其作用机理。该文综述了土壤pH、温度、可利用碳源、氧化还原电位对PCBs降解的影响及根际土壤中微生物、酶、根系分泌物促进PCBs降解的机理,并讨论了PCBs浓度及种类、植物生物量、土壤有机物老化等方面在土壤PCBs根际降解过程中的作用,最后基于当前研究的不足提出未来研究中可能需要引起重视的几个方面,可为今后深入推广该领域的工程应用提供一定的参考。

Polychlorinated biphenyls(PCBs)are a kind of persistent organic pollutants.Due to the extensive production and use of industrial manufacturing industry in various countries since the 19 th century,a large number of PCBs have entered the soil environment through various ways.Soil PCBs pollution has gradually become one of the most important problems that threaten the safety of human life and restrict the rapid development of society.After entering the 21 st century,phytoremediation technology has gradually become a research hotspot in remediation of PCBs-contaminated soil due to its green and economic concepts.Many studies have also confirmed the remediation effect of phytoremediation on PCBs contaminated soil,but few relevant literatures have discussed the great significance and mechanism of rhizosphere degradation in PCBs contaminated soil.This article reviews the effects of soil pH,temperature,available carbon sources,and redox potential(Eh)on PCBs degradation,as well as the mechanisms by which microorganisms,enzymes and root exudates in rhizosphere soil promote PCBs degradation.Subsequently,this paper discusses the function of concentration and types of PCBs,plant biomass,soil organic matter aging in the degradation process of soil PCBs rhizosphere.Finally,based on the shortcomings of current research,several aspects that may need to be paid attention in future research are put forward,which will provide some advice for the further promotion of engineering applications in this field in the future.