Composting presents a viable management solution for lignocellulose-rich municipal solid waste.However,our understanding about the microbial metabolic mechanisms involved in the biodegradation of lignocellulose,partic...Composting presents a viable management solution for lignocellulose-rich municipal solid waste.However,our understanding about the microbial metabolic mechanisms involved in the biodegradation of lignocellulose,particularly in industrial-scale composting plants,remains limited.This study employed metaproteomics to compare the impact of upgrading from aerated static pile(ASP)to agitated bed(AB)systems on physicochemical parameters,lignocellulose biodegradation,and microbial metabolic pathways during largescale biowaste composting process,marking the first investigation of its kind.The degradation rates of lignocellulose including cellulose,hemicellulose,and lignin were significantly higher in AB(8.21%-32.54%,10.21%-39.41%,and 6.21%-26.78%)than those(5.72%-23.15%,7.01%-33.26%,and 4.79%-19.76%)in ASP at three thermal stages,respectively.The AB system in comparison to ASP increased the carbohydrate-active enzymes(CAZymes)abundance and production of the three essential enzymes required for lignocellulose decomposition involving a mixture of bacteria and fungi(i.e.,Actinobacteria,Bacilli,Sordariomycetes and Eurotiomycetes).Conversely,ASP primarily produced exoglucanase andβ-glucosidase via fungi(i.e.,Ascomycota).Moreover,AB effectively mitigated microbial stress caused by acetic acid accumulation by regulating the key enzymes involved in acetate conversion,including acetyl-coenzyme A synthetase and acetate kinase.Overall,the AB upgraded from ASP facilitated the lignocellulose degradation and fostered more diverse functional microbial communities in large-scale composting.Our findings offer a valuable scientific basis to guide the engineering feasibility and environmental sustainability for large-scale industrial composting plants for treating lignocellulose-rich waste.These findings have important implications for establishing green sustainable development models(e.g.,a circular economy based onmaterial recovery)and for achieving sustainable development goals.展开更多
Both microplastic(MP)pollution and zinc(Zn)deficiency have adverse effects on terrestrial plants.However,the combined effect of MPs and Zn deficiency on plant physiology remains unexplored.In this study,a pot-culture ...Both microplastic(MP)pollution and zinc(Zn)deficiency have adverse effects on terrestrial plants.However,the combined effect of MPs and Zn deficiency on plant physiology remains unexplored.In this study,a pot-culture experiment and ^(13)C stable isotope tracing technology were employed to investigate the combined effects of MPs and Zn deficiency on the growth,photosynthetic physiology and chlorophyll fluorescence characteristics,as well as synthesis and distribution of photosynthetic products in Malus hupehensis(Pamp.)Rehd seedlings.The results revealed significant reductions in biomass,gas exchange parameters,carbohydrate metabolism enzyme activities,and photosynthetic parameters including Fv/Fm,FPSII,ETR and qp in seedlings subjected to both individual and joint treatments of MPs and Zn deficiency compared to the control group.Notably,the combined Zn deficiency and MPs exhibited a more pronounced inhibitory effect on root biomass(RR=-0.42)compared to the single Zn deficiency(RR=-0.37)and MP(RR=-0.26)treatments.Random forest analysis indicated that chlorophyll fluorescence characteristics(37.5%)had the greatest impact on biomass variation in seedlings,followed by ^(13)C accumulation in various organs(26.7%).MPs exacerbated the inhibition of photosynthesis(Pn and Gs)under Zn deficiency by suppressing chlorophyll fluorescence parameters(Fv/Fm and FPSII),further reducing ^(13)C accumulation in roots.In conclusion,the addition of MPs intensified the suppression of photosynthetic parameters caused by Zn deficiency,weakened the carbon assimilation capacity of leaves,and hindered the synthesis of photosynthetic products in leaves and their transport to roots,thereby further inhibiting root growth.This study reveals the combined stress of MP pollution and Zn deficiency on terrestrial plants,deepens our understanding of potential ecological risks,and provides scientific basis for the development of effective mitigation measures to protect plant ecosystems.展开更多
Aims Natural hybridization between invasive and native species,as a form of adaptive evolution,threatens biodiversity worldwide.However,the potential invasive mechanisms of hybrids remain essentially unexplored,especi...Aims Natural hybridization between invasive and native species,as a form of adaptive evolution,threatens biodiversity worldwide.However,the potential invasive mechanisms of hybrids remain essentially unexplored,especially insights from soil chemical properties and soil microbial communities.Methods In a field experiment,soil microbial community,potassium-solubilizing bacteria,phosphorus-solubilizing bacteria,enzyme activities,and light-saturated photosynthetic rate were measured in invasive Sphagneticola trilobata and its hybrid with native Sphagneticola calendulacea in 2 years.Important Findings In general,soil dissolved organic carbon and the biomass of phosphorus-solubilizing bacteria were significantly higher under the hybrid treatment than S.trilobata and S.calendulacea.However,there were no significant differences in acid phosphatase,total PLFAs,bacterial PLFAs,fungi PLFAs,cellulase,and urase in these treatments.The hybrids had significantly higher light-saturated photosynthetic rate,photosynthetic nitrogen-,phosphorus-,potassium-use efficiencies than the invasive S.trilobata,but no significant difference with S.calendulacea.The total biomass and root biomass of hybrids were higher than S.calendulacea.Our results indicate that the hybrids species have a higher invasive potential than S.calendulacea,which may aggravate the local extinction of S.calendulacea in the future.展开更多
基金This work was supported by the National Natural Science Foundation of China(No.42030704).
文摘Composting presents a viable management solution for lignocellulose-rich municipal solid waste.However,our understanding about the microbial metabolic mechanisms involved in the biodegradation of lignocellulose,particularly in industrial-scale composting plants,remains limited.This study employed metaproteomics to compare the impact of upgrading from aerated static pile(ASP)to agitated bed(AB)systems on physicochemical parameters,lignocellulose biodegradation,and microbial metabolic pathways during largescale biowaste composting process,marking the first investigation of its kind.The degradation rates of lignocellulose including cellulose,hemicellulose,and lignin were significantly higher in AB(8.21%-32.54%,10.21%-39.41%,and 6.21%-26.78%)than those(5.72%-23.15%,7.01%-33.26%,and 4.79%-19.76%)in ASP at three thermal stages,respectively.The AB system in comparison to ASP increased the carbohydrate-active enzymes(CAZymes)abundance and production of the three essential enzymes required for lignocellulose decomposition involving a mixture of bacteria and fungi(i.e.,Actinobacteria,Bacilli,Sordariomycetes and Eurotiomycetes).Conversely,ASP primarily produced exoglucanase andβ-glucosidase via fungi(i.e.,Ascomycota).Moreover,AB effectively mitigated microbial stress caused by acetic acid accumulation by regulating the key enzymes involved in acetate conversion,including acetyl-coenzyme A synthetase and acetate kinase.Overall,the AB upgraded from ASP facilitated the lignocellulose degradation and fostered more diverse functional microbial communities in large-scale composting.Our findings offer a valuable scientific basis to guide the engineering feasibility and environmental sustainability for large-scale industrial composting plants for treating lignocellulose-rich waste.These findings have important implications for establishing green sustainable development models(e.g.,a circular economy based onmaterial recovery)and for achieving sustainable development goals.
基金supported by the National Natural Science Foundation of China(No.42107440).
文摘Both microplastic(MP)pollution and zinc(Zn)deficiency have adverse effects on terrestrial plants.However,the combined effect of MPs and Zn deficiency on plant physiology remains unexplored.In this study,a pot-culture experiment and ^(13)C stable isotope tracing technology were employed to investigate the combined effects of MPs and Zn deficiency on the growth,photosynthetic physiology and chlorophyll fluorescence characteristics,as well as synthesis and distribution of photosynthetic products in Malus hupehensis(Pamp.)Rehd seedlings.The results revealed significant reductions in biomass,gas exchange parameters,carbohydrate metabolism enzyme activities,and photosynthetic parameters including Fv/Fm,FPSII,ETR and qp in seedlings subjected to both individual and joint treatments of MPs and Zn deficiency compared to the control group.Notably,the combined Zn deficiency and MPs exhibited a more pronounced inhibitory effect on root biomass(RR=-0.42)compared to the single Zn deficiency(RR=-0.37)and MP(RR=-0.26)treatments.Random forest analysis indicated that chlorophyll fluorescence characteristics(37.5%)had the greatest impact on biomass variation in seedlings,followed by ^(13)C accumulation in various organs(26.7%).MPs exacerbated the inhibition of photosynthesis(Pn and Gs)under Zn deficiency by suppressing chlorophyll fluorescence parameters(Fv/Fm and FPSII),further reducing ^(13)C accumulation in roots.In conclusion,the addition of MPs intensified the suppression of photosynthetic parameters caused by Zn deficiency,weakened the carbon assimilation capacity of leaves,and hindered the synthesis of photosynthetic products in leaves and their transport to roots,thereby further inhibiting root growth.This study reveals the combined stress of MP pollution and Zn deficiency on terrestrial plants,deepens our understanding of potential ecological risks,and provides scientific basis for the development of effective mitigation measures to protect plant ecosystems.
基金funded by the National Natural Science Foundation of China(41907023,31870374)the China Postdoctoral Science Foundation(2018M643112)and the China Postdoctoral Science Foundation(2018M643112)+1 种基金the State Key Laboratory for Biology of Plant Diseases and Insect Pests(SKLOF201914)supported by Guangdong Province Natural Science Foundation(2017A030313167,2015A030311023).
文摘Aims Natural hybridization between invasive and native species,as a form of adaptive evolution,threatens biodiversity worldwide.However,the potential invasive mechanisms of hybrids remain essentially unexplored,especially insights from soil chemical properties and soil microbial communities.Methods In a field experiment,soil microbial community,potassium-solubilizing bacteria,phosphorus-solubilizing bacteria,enzyme activities,and light-saturated photosynthetic rate were measured in invasive Sphagneticola trilobata and its hybrid with native Sphagneticola calendulacea in 2 years.Important Findings In general,soil dissolved organic carbon and the biomass of phosphorus-solubilizing bacteria were significantly higher under the hybrid treatment than S.trilobata and S.calendulacea.However,there were no significant differences in acid phosphatase,total PLFAs,bacterial PLFAs,fungi PLFAs,cellulase,and urase in these treatments.The hybrids had significantly higher light-saturated photosynthetic rate,photosynthetic nitrogen-,phosphorus-,potassium-use efficiencies than the invasive S.trilobata,but no significant difference with S.calendulacea.The total biomass and root biomass of hybrids were higher than S.calendulacea.Our results indicate that the hybrids species have a higher invasive potential than S.calendulacea,which may aggravate the local extinction of S.calendulacea in the future.
