微/纳米塑料对厌氧消化系统影响的研究进展

Research progress in the effects of micro(nano)plastics on anaerobic digestion system

生物质废弃物联合剩余活性污泥(waste activated sludge,WAS)进行厌氧消化(anaerobic digestion,AD)是WAS稳定化和产甲烷的一种有效稳定的技术,可有效减少WAS体积,提高WAS脱水效果,并且具有稳定性好、能耗低、产沼气的特点,因而被广泛应用。然而AD过程容易受到外部因素如微塑料(microplastics,MPs)或纳米塑料(nanoplastics,NPs)的影响,从而导致AD效率降低甚至崩溃。AD过程的稳定运行需要微生物菌群之间相互依存、相互作用,使其处于动态的平衡状态,噬菌体在此平衡过程占有重要的地位,其不仅能够调控污泥菌群结构和控制能量的流向,而且能够与细菌、古菌附着在MPs和NPs上进行传播,但在以往的MPs和NPs研究中往往被忽视。本文综述了不同类型、尺寸的MPs和NPs对AD系统影响的研究进展,并聚焦于厌氧系统中微生物群落间,尤其是细菌、古菌与噬菌体的生态关系,针对MPs和NPs对微生物群落的影响与改变提出了不同的见解,并展望了MPs和NPs对AD系统影响方面的未来研究方向。

Anaerobic digestion(AD)of biomass waste combined with waste activated sludge(WAS),which is characterized by great stability,low energy consumption,and biogas production,can effectively reduce the volume and improve the dehydration of WAS and thus has been widely applied in methane production.However,the AD process is susceptible to external factors such as microplastics(MPs)or nanoplastics(NPs),which can lead to reduced efficiency or even collapse of AD.The AD system needs the interdependence and interaction of the microbial community to keep stable operation in a dynamic equilibrium state,in which phages play a key role.Phages can not only regulate the structure of the microbial community in the sludge and direct the energy flow but also attach to MPs and NPs with bacteria and archaea for transmission.Nevertheless,the effects of MPs and NPs on such a process were underestimated in previous studies.In this paper,we summarize the research progress in the effects of different types and sizes of MPs and NPs on AD systems,with focus on the ecological connections among microbial communities,especially bacteria,archaea,and phages,in anaerobic systems.Furthermore,we put forward novel viewpoints about the effects of MPs and NPs on microbial communities and make an outlook on the future research directions in this field.