Microplastics(MPs)in river ecosystems significantly affect sediment microbial communities and biogeochemical cycling.However,the specific microbial responses to distinct MPs and their subsequent effects on greenhouse ...Microplastics(MPs)in river ecosystems significantly affect sediment microbial communities and biogeochemical cycling.However,the specific microbial responses to distinct MPs and their subsequent effects on greenhouse gas(GHG)emissions remain poorly understood.In this study,the effects of conventional polyvinyl chloride(PVC)and biodegradable polylactic acid(PLA)on sediment microbial communities and GHG emissions were compared.Both PVC and PLA increased sediment total organic carbon(STOC)by 31.3%and 36.7%,respectively,leading to an increase in sediment bacterial abundance.Notably,compared with PLA,PVC reduced bacterial richness more significantly.Community composition and FAPROTAX function prediction analysis revealed that PVC-enriched taxa involved in nitrate reduction(e.g.,Desulfuromonas,Hydrogenophage,Azospira)resulted in a significant decrease in NO3−contents.In contrast,PLA increased the abundance of microorganisms associated with organic matter degradation(Chitinophagaceae,Comamonadaceae,and Caulobacteraceae).Both PVC and PLA significantly reduced the relative abundance of the mcrA gene,leading to decreased CH4 fluxes,likely due to competition from enriched acetate-utilizing bacteria(Desulfuromonas,Pseudomonas,and Azospira).Additionally,PLA significantly reduced the abundance of the nirK gene.This study systematically elucidates the differential effects of PVC and PLA on microbial community structure and GHG emissions,providing new insights into the ecological impacts of MPs.展开更多
"非 X 不可"格式产生于先秦时期,发展至今经历了结构语法化和功能语法化。其结构语法化包括格式的凝固化、有界化和 X 的谓词化,其功能语法化起始于清代末年,而广泛发生于20世纪上半叶,"非……不可"由命题谓语语法..."非 X 不可"格式产生于先秦时期,发展至今经历了结构语法化和功能语法化。其结构语法化包括格式的凝固化、有界化和 X 的谓词化,其功能语法化起始于清代末年,而广泛发生于20世纪上半叶,"非……不可"由命题谓语语法化为表示情态意义的高位谓语,并由此导致了情态副词"非"的产生。展开更多
基金supported by the Fund for National Key R&D Program of China(2021YFC3200401)the National Natural Science Foundation of China(Grant Nos.52170024 and 52039001).
文摘Microplastics(MPs)in river ecosystems significantly affect sediment microbial communities and biogeochemical cycling.However,the specific microbial responses to distinct MPs and their subsequent effects on greenhouse gas(GHG)emissions remain poorly understood.In this study,the effects of conventional polyvinyl chloride(PVC)and biodegradable polylactic acid(PLA)on sediment microbial communities and GHG emissions were compared.Both PVC and PLA increased sediment total organic carbon(STOC)by 31.3%and 36.7%,respectively,leading to an increase in sediment bacterial abundance.Notably,compared with PLA,PVC reduced bacterial richness more significantly.Community composition and FAPROTAX function prediction analysis revealed that PVC-enriched taxa involved in nitrate reduction(e.g.,Desulfuromonas,Hydrogenophage,Azospira)resulted in a significant decrease in NO3−contents.In contrast,PLA increased the abundance of microorganisms associated with organic matter degradation(Chitinophagaceae,Comamonadaceae,and Caulobacteraceae).Both PVC and PLA significantly reduced the relative abundance of the mcrA gene,leading to decreased CH4 fluxes,likely due to competition from enriched acetate-utilizing bacteria(Desulfuromonas,Pseudomonas,and Azospira).Additionally,PLA significantly reduced the abundance of the nirK gene.This study systematically elucidates the differential effects of PVC and PLA on microbial community structure and GHG emissions,providing new insights into the ecological impacts of MPs.
