Resilience and functional redundancy of methanogenic digestion microbiome safeguard recovery of methanogenesis activity under the stress induced by microplastics  

作　　者：Jinting Liu Guofang Xu Siyan Zhao Jianzhong He 

机构地区：[1]Department of Civil and Environmental Engineering,National University of Singapore,Singapore

出　　处：《mLife》2023年第4期378-388,共11页微生物（英文）

基　　金：supported by the Ministry of Education,Singapore,under Academic Research Fund Tier 2 under project No.:MOE-000033-01;Tier 1 under Project No.:R-302-000-239-114。

摘　　要：Microplastics and nanoplastics are emerging pollutants that substantially influence biological element cycling in natural ecosystems.Plastics are also prevalent in sewage,and they accumulate in waste-activated sludge(WAS).However,the impacts of plastics on the methanogenic digestion of WAS and the underpinning microbiome remain underexplored,particularly during long-term operation.In this study,we found that short-term exposure to individual microplastics and nanoplastics(polyethylene,polyvinyl chloride,polystyrene,and polylactic acid)at a low concentration(10 particles/g sludge)slightly enhanced methanogenesis by 2.1%−9.0%,whereas higher levels(30−200 particles/g sludge)suppressed methanogenesis by 15.2%−30.1%.Notably,the coexistence of multiple plastics,particularly at low concentrations,showed synergistic suppression of methanogenesis.Unexpectedly,methanogenesis activity completely recovered after long-term exposure to plastics,despite obvious suppression of methanogenesis by initial plastic exposure.The inhibition of methanogenesis by plastics could be attributed to the stimulated generation of reactive oxygen species.The stress induced by plastics dramatically decreased the relative abundance of methanogens but showed marginal influence on putative hydrolytic and fermentation populations.Nonetheless,the digestion sludge microbiome exhibited resilience and functional redundancy,contributing to the recovery of methanogenesis during the long-term operation of digesters.Plastics also increased the complexity,modularity,and negative interaction ratios of digestion sludge microbiome networks,but their influence on community assembly varied.Interestingly,a unique plastisphere was observed,the networks and assembly of which were distinct from the sludge microbiome.Collectively,the comprehensive evaluation of the influence of microplastics and nanoplastics on methanogenic digestion,together with the novel ecological insights,contribute to better understanding and manipulating this engineered ecosystem in the fa

关 键 词：functional redundancy methanogenic digestion microbial ecology microplastics RESILIENCE 

分 类 号：TQ221.11[化学工程—有机化工] X705[环境科学与工程—环境工程]