植物影响空气中持久性有机污染物的研究进展

Research progress on effects of vegetation on persistent organic pollutants(POPs)in the air

持久性有机污染物(POPs)在植物与空气两相界面之间存在动态交换过程,一方面,植物叶片吸附、吸收空气中的POPs,净化了空气,并将其转移到食物链和土壤等其它环境介质中;另一方面,植物叶片通过挥发使其吸附的POPs重新回到空气中,最终对全球范围内POPs的循环和环境归趋产生重要影响.本文综述了植物与空气中POPs的动态交换过程,分析了影响植物吸附和挥发POPs的主要因素,包括POPs的理化性质、植物特征和环境条件.同时,就城市绿地对空气中POPs浓度水平的影响展开讨论,由于该过程受多种因素共同影响,植被清除的POPs是否足以改善空气质量仍有争议,其中影响机制有待深入研究.此外,本文总结了植物中POPs的检测技术,传统检测技术灵敏性和准确性高,而原位检测技术可以直接观察活体植物中POPs的吸收、迁移、存储等环境行为.最后,本文探讨了现有研究的不足和未来发展的方向,以期为今后研究植物-空气界面过程以及POPs多介质环境行为提供理论和技术参考.

The mass exchange of persistent organic pollutants(POPs)between vegetation and air is a dynamic process.For one thing,vegetation can capture atmospheric POPs,and clean up air.The accumulation of POPs in vegetation is further transferred to food chain and other environmental media(soil).For another,POPs in vegetation can be re-volatilized to the air.The capture and re-volatilization process of POPs will influence the cycling and fate of POPs in the global scale.This paper reviewed comprehensively the vegetation-air exchange process of POPs and its main factors,including physic-chemical property of pollutants,characterization of vegetation,and ambient condition.And this review explored the influence of green land on atmospheric POPs in urban environment.It is still controversial that whether POPs removed by vegetation is sufficient to improve the air quality,because the removal process involved in many factors and the influence mechanism has been unclear until now.In addition,this study summarized detection technologies of POPs in vegetation.Traditional detection methods had high sensitivity and accuracy,while in-situ detection technology observed the uptake,transport and storage of POPs in living vegetation.Finally,challenges in current research and direction in further investigation were addressed.We hope that this paper can provide a valuable reference for the vegetation-air exchange process and environmental behavior of POPs in multimedia.