Effective vegetation reconstruction plays a vital role in the restoration of desert ecosystems.However,in reconstruction of different vegetation types,the community characteristics,assembly processes,and functions of ...Effective vegetation reconstruction plays a vital role in the restoration of desert ecosystems.However,in reconstruction of different vegetation types,the community characteristics,assembly processes,and functions of different soil microbial taxa under environmental changes are still disputed,which limits the understanding of the sustainability of desert restoration.Hence,we investigated the soil microbial community characteristics and functional attributes of grassland desert(GD),desert steppe(DS),typical steppe(TS),and artificial forest(AF)in the Mu Us Desert,China.Our findings confirmed the geographical conservation of soil microbial composition but highlighted decreased microbial diversity in TS.Meanwhile,the abundance of rare taxa and microbial community stability in TS improved.Heterogeneous and homogeneous selection determined the assembly of rare and abundant bacterial taxa,respectively,with both being significantly influenced by soil moisture.In contrast,fungal communities displayed stochastic processes and exhibited sensitivity to soil nutrient conditions.Furthermore,our investigation revealed a noteworthy augmentation in bacterial metabolic functionality in TS,aligning with improved vegetation restoration and the assemblage of abundant bacterial taxa.However,within nutrient-limited soils(GD,DS,and AF),the assembly dynamics of rare fungal taxa assumed a prominent role in augmenting their metabolic capacity and adaptability to desert ecosystems.These results highlighted the variations in the assembly processes and metabolic functions of soil microorganisms during vegetation reestablishment and provided corresponding theoretical support for anthropogenic revegetation of desert ecosystems.展开更多
Lake mixing influences aquatic chemical properties and microbial community composition,and thus,we hypothesized that it would alter microbial community assembly and interac-tion.To clarify this issue,we explored the c...Lake mixing influences aquatic chemical properties and microbial community composition,and thus,we hypothesized that it would alter microbial community assembly and interac-tion.To clarify this issue,we explored the community assembly processes and cooccurrence networks in four seasons at two depths(epilimnion and hypolimnion)in a mesotrophic and stratified lake(Chenghai Lake),which formed stratification in the summer and turnover in the winter.During the stratification period,the epilimnion and hypolimnion went through contrary assembly processes but converged to similar assembly patterns in the mixing pe-riod.In a highly homogeneous selection environment,species with low niche breadth were filtered,resulting in decreased species richness.Water mixing in the winter homogenized the environment,resulting in a simpler microbial cooccurrence network.Interestingly,we observed a high abundance of the cyanobacterial genus Planktothrix in the winter,proba-bly due to nutrient redistribution and Planktothrix adaptivity to the winter environment in which mixing played important roles.Our study provides deeper fundamental insights into how environmental factors influence microbial community structure through community assembly processes.展开更多
Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of f...Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of fungicides for managing rice seedling blight,there has been a shift in focus towards biological control agents.In this study,we isolated biocontrol bacteria from paddy fields that significantly inhibited the growth of F.oxysporum in vitro and identified the strains as Bacillus amyloliquefaciens T40 and Bacillus pumilus T208.Additionally,our findings indicated that the combined application of these Bacillus strains in soil was more effective in reducing the incidence of rice seedling blight than their individual use.Analysis of 16S and internal transcribed spacer rRNA gene sequencing data revealed that the mixture of the T40 and T208 strains exhibited the lowest average clustering coefficients,which were negatively correlated with the biomass of F.oxysporum-inoculated rice seedlings.Furthermore,this mixture led to higher stochastic assembly(average|βNTI|<2)and reduced selection pressures on rice rhizosphere bacteria compared with individual strain applications.The mixture of the T40 and T208 strains also significantly increased the expression of defense-related genes.In conclusion,the mixture of the T40 and T208 strains effectively modulates microbial community structures,enhances microbial network stability,and boosts the resistance against rice seedling blight.Our study supports the development and utilization of biological resources for crop protection.展开更多
Plant roots are one of the major mediators that allocate carbon captured from the atmosphere to soils as rhizodeposits,including root exudates.Although rhizodeposition regulates both microbial activity and the biogeoc...Plant roots are one of the major mediators that allocate carbon captured from the atmosphere to soils as rhizodeposits,including root exudates.Although rhizodeposition regulates both microbial activity and the biogeochemical cycling of nutrients,the effects of particular exudate species on soil carbon fluxes and key rhizosphere microorganisms remain unclear.By combining high-throughput sequencing,q-PCR,and NanoSIMS analyses,we characterized the bacterial community structure,quantified total bacteria depending on root exudate chemistry,and analyzed the consequences on the mobility of mineral-protected carbon.Using well-controlled incubation experiments,we showed that the three most abundant groups of root exudates(amino acids,carboxylic acids,and sugars)have contrasting effects on the release of dissolved organic carbon(DOC)and bioavailable Fe in an Ultisol through the disruption of organo-mineral associations and the alteration of bacterial communities,thus priming organic matter decomposition in the rhizosphere.High resolution(down to 50 nm)NanoSIMS images of mineral particles indicated that iron and silicon colocalized significantly more organic carbon following amino acid inputs than treatments without exudates or with carboxylic acids.The application of sugar strongly reduced microbial diversity without impacting soil carbon mobilization.Carboxylic acids increased the prevalence of Actinobacteria and facilitated carbon mobilization,whereas amino acid addition increased the abundances of Proteobacteria that prevented DOC release.In summary,root exudate functions are defined by their chemical composition that regulates bacterial community composition and,consequently,the biogeochemical cycling of carbon in the rhizosphere.展开更多
The complex current systems of the Southern Ocean play a critical role in shaping the heterogeneity and distinctiveness of Antarctic habitats.Nonetheless,how Antarctic water masses influence ciliates,one of the most c...The complex current systems of the Southern Ocean play a critical role in shaping the heterogeneity and distinctiveness of Antarctic habitats.Nonetheless,how Antarctic water masses influence ciliates,one of the most common groups of protozoa in polar regions,remains largely unknown.The present study investigated how the ciliate communities are affected by com-plex Southern Ocean currents by analyzing the diversity distributions,community assembly mechanisms,and co-occurrence networks of ciliates across three distinct water masses in the Scotia Sea.The findings reveal that the hydrography of the Scotia Sea significantly affects the spatial patterns of planktonic ciliates,primarily through the combination of temperature,salinity,and depth.In contract to surface waters(Antarctic Surface Water and Antarctic Circumpolar Current),ciliates inhab-iting deep waters(Circumpolar Deep Water)exhibit stronger and more direct correlations with the environment parameters,alongside greater network stability.Community assembly in surface and deep-water masses is governed by stochastic and deterministic processes,respectively.Compared to other Antarctic regions documented in previous studies,the Scotia Sea demonstrated the lowest alpha diversity indices for ciliates while harboring the highest number of endemic species.A detailed re-evaluation of Antarctic ciliate community structure in the Antarctic from prior research offers valuable insights into how dynamic ocean currents shape the ecological dynamics of ciliate communities,thus providing a broader understanding of the environmental changes impacting polar marine ecosystems.展开更多
Soil microbes play a critical role in maintaining the health and stability of these ecosystems. However, the ecological assembly processes of soil microbial communities remain poorly understood. This study explores th...Soil microbes play a critical role in maintaining the health and stability of these ecosystems. However, the ecological assembly processes of soil microbial communities remain poorly understood. This study explores the changes in ecological components across original and degraded patches of alpine meadows in Sanjiangyuan National Park and analyzed soil microbial community structure using high-throughput sequencing techniques. Results showed that alpine meadows degradation increased vegetation species diversity, significantly reduced aboveground productivity, and made the soil more barren and alkaline. Although the dominant phyla of soil microorganisms were similar across different degradation states, degradation significantly increased the relative abundance of oligotrophic bacteria and decreased the relative abundance of dominant fungi. Additionally, microbial communities exhibited significant β-diversity. Degradation also led to an increase in microbial α-diversity, heightened microbial taxa competition and a more complex microbial co-occurrence network. However, vegetation-soil variables explained only a small portion of the variation in soil microbes. Through the study of microbial ecological assembly processes, we found that degradation enhanced the stochastic processes of soil microbial communities, and the changes in soil microbial communities were mainly driven by the variations inherent in the microbes themselves. These findings highlight the complex ecological interactions between above- and belowground components and emphasize the critical role of microbial community dynamics qin mediating ecosystem functions.展开更多
Conventional biological treatment usually cannot achieve the same high water quality as advanced treatment when conducted under varied temperatures.Here,satisfactory wastewater treatment efficiency was observed in a m...Conventional biological treatment usually cannot achieve the same high water quality as advanced treatment when conducted under varied temperatures.Here,satisfactory wastewater treatment efficiency was observed in a microalgae-bacteria consortia(MBC)over a wide temperature range because of the predominance of microalgae.Microalgae contributed more toward wastewater treatment at low temperature because of the unsatisfactory performance of the accompanying bacteria,which experienced cold stress(e.g.,bacterial abundance below 3000 sequences)and executed defensive strategies(e.g.,enrichment of cold-shock proteins).A low abundance of amoA-C and hao indicated that conventional nitrogen removal was replaced through the involvement of microalgae.Diverse heterotrophic bacteria for nitrogen removal were identified at medium and high temperatures,implying this microbial niche treatment contained diverse flexible consortia with temperature variation.Additionally,pathogenic bacteria were eliminated through microalgal photosynthesis.After fitting the neutral community model and calculating the ecological niche,microalgae achieved a maximum niche breadth of 5.21 and the lowest niche overlap of 0.38,while the accompanying bacterial community in the consortia were shaped through deterministic processes.Finally,the maximum energy yield of 87.4 kJ L^(-1)and lipid production of 1.9 g L^(-1)were achieved at medium temperature.Altogether,this study demonstrates that advanced treatment and energy reclamation can be achieved through microalgae-bacteria niche strategies.展开更多
基金supported by the National Natural Science Foundation of China(No.42007428)the National Forage Industry Technology System Program of China(No.CARS34)+1 种基金the Key Research and Development Program of Shaanxi,China(No.2022SF-285)Shaanxi Province Forestry Science and Technology Innovation Program,China(No.SXLK2022-02-14)。
文摘Effective vegetation reconstruction plays a vital role in the restoration of desert ecosystems.However,in reconstruction of different vegetation types,the community characteristics,assembly processes,and functions of different soil microbial taxa under environmental changes are still disputed,which limits the understanding of the sustainability of desert restoration.Hence,we investigated the soil microbial community characteristics and functional attributes of grassland desert(GD),desert steppe(DS),typical steppe(TS),and artificial forest(AF)in the Mu Us Desert,China.Our findings confirmed the geographical conservation of soil microbial composition but highlighted decreased microbial diversity in TS.Meanwhile,the abundance of rare taxa and microbial community stability in TS improved.Heterogeneous and homogeneous selection determined the assembly of rare and abundant bacterial taxa,respectively,with both being significantly influenced by soil moisture.In contrast,fungal communities displayed stochastic processes and exhibited sensitivity to soil nutrient conditions.Furthermore,our investigation revealed a noteworthy augmentation in bacterial metabolic functionality in TS,aligning with improved vegetation restoration and the assemblage of abundant bacterial taxa.However,within nutrient-limited soils(GD,DS,and AF),the assembly dynamics of rare fungal taxa assumed a prominent role in augmenting their metabolic capacity and adaptability to desert ecosystems.These results highlighted the variations in the assembly processes and metabolic functions of soil microorganisms during vegetation reestablishment and provided corresponding theoretical support for anthropogenic revegetation of desert ecosystems.
基金This work was supported by the National Natural Science Foundation of China(No.51578537)Chinese Academy of Sciences(No.QYZDY-SSW-DQC004)。
文摘Lake mixing influences aquatic chemical properties and microbial community composition,and thus,we hypothesized that it would alter microbial community assembly and interac-tion.To clarify this issue,we explored the community assembly processes and cooccurrence networks in four seasons at two depths(epilimnion and hypolimnion)in a mesotrophic and stratified lake(Chenghai Lake),which formed stratification in the summer and turnover in the winter.During the stratification period,the epilimnion and hypolimnion went through contrary assembly processes but converged to similar assembly patterns in the mixing pe-riod.In a highly homogeneous selection environment,species with low niche breadth were filtered,resulting in decreased species richness.Water mixing in the winter homogenized the environment,resulting in a simpler microbial cooccurrence network.Interestingly,we observed a high abundance of the cyanobacterial genus Planktothrix in the winter,proba-bly due to nutrient redistribution and Planktothrix adaptivity to the winter environment in which mixing played important roles.Our study provides deeper fundamental insights into how environmental factors influence microbial community structure through community assembly processes.
基金supported by the Zhejiang Provincial Natural Science Foundation,China(Grant No.LQ24C010007)Zhejiang Science and Technology Major Program on Rice New Variety Breeding,China(Grant No.2021C02063)+4 种基金the Agricultural Sciences and Technologies Innovation Program,China(Grant No.CAAS-CSCB-202301)the Key Projects of Zhejiang Provincial Natural Science Foundation,China(Grant No.LZ23C130002)the Youth Innovation Program of Chinese Academy of Agricultural Sciences(Grant No.Y2023QC22)the Joint Open Competitive Project of the Yazhou Bay Seed Laboratory and China National Seed Company Limited(Grant Nos.B23YQ1514 and B23CQ15EP)the External Cooperation Projects of Biotechnology Research Institute,Fujian Academy of Agricultural Sciences,China(Grant No.DWHZ2024-07).
文摘Rice seedling blight,caused by various fungi,including Fusarium oxysporum,poses a severe threat to rice production.As awareness grows regarding the environmental and safety hazards associated with the application of fungicides for managing rice seedling blight,there has been a shift in focus towards biological control agents.In this study,we isolated biocontrol bacteria from paddy fields that significantly inhibited the growth of F.oxysporum in vitro and identified the strains as Bacillus amyloliquefaciens T40 and Bacillus pumilus T208.Additionally,our findings indicated that the combined application of these Bacillus strains in soil was more effective in reducing the incidence of rice seedling blight than their individual use.Analysis of 16S and internal transcribed spacer rRNA gene sequencing data revealed that the mixture of the T40 and T208 strains exhibited the lowest average clustering coefficients,which were negatively correlated with the biomass of F.oxysporum-inoculated rice seedlings.Furthermore,this mixture led to higher stochastic assembly(average|βNTI|<2)and reduced selection pressures on rice rhizosphere bacteria compared with individual strain applications.The mixture of the T40 and T208 strains also significantly increased the expression of defense-related genes.In conclusion,the mixture of the T40 and T208 strains effectively modulates microbial community structures,enhances microbial network stability,and boosts the resistance against rice seedling blight.Our study supports the development and utilization of biological resources for crop protection.
基金supported by National Natural Science Foundation of China(Grants No.31902107 and 41977271)Natural Science Foundation of Jiangsu Province(Grant No.BK20211577)+3 种基金the Innovative Research Team Development Plan of the Ministry of Education of China(Grant No.IRT_17R56)supported by Qing Lan Project of Jiangsu Provincethe support by the RUDN University Strategic Academic Leadership Programthe WeChat subscription ID“meta-Genome”and“Micro-Bioinformatics and microflora”for the analysis methods.
文摘Plant roots are one of the major mediators that allocate carbon captured from the atmosphere to soils as rhizodeposits,including root exudates.Although rhizodeposition regulates both microbial activity and the biogeochemical cycling of nutrients,the effects of particular exudate species on soil carbon fluxes and key rhizosphere microorganisms remain unclear.By combining high-throughput sequencing,q-PCR,and NanoSIMS analyses,we characterized the bacterial community structure,quantified total bacteria depending on root exudate chemistry,and analyzed the consequences on the mobility of mineral-protected carbon.Using well-controlled incubation experiments,we showed that the three most abundant groups of root exudates(amino acids,carboxylic acids,and sugars)have contrasting effects on the release of dissolved organic carbon(DOC)and bioavailable Fe in an Ultisol through the disruption of organo-mineral associations and the alteration of bacterial communities,thus priming organic matter decomposition in the rhizosphere.High resolution(down to 50 nm)NanoSIMS images of mineral particles indicated that iron and silicon colocalized significantly more organic carbon following amino acid inputs than treatments without exudates or with carboxylic acids.The application of sugar strongly reduced microbial diversity without impacting soil carbon mobilization.Carboxylic acids increased the prevalence of Actinobacteria and facilitated carbon mobilization,whereas amino acid addition increased the abundances of Proteobacteria that prevented DOC release.In summary,root exudate functions are defined by their chemical composition that regulates bacterial community composition and,consequently,the biogeochemical cycling of carbon in the rhizosphere.
基金supported by the Science and Technology Innovation Project of Laoshan Laboratory(LSKJ202203205)National Natural Science Foundation of China(NFSC)(Nos.42276156,42206147,32100404)Natural Science Foundation of Shandong Province of China(No.ZR2021QC045).
文摘The complex current systems of the Southern Ocean play a critical role in shaping the heterogeneity and distinctiveness of Antarctic habitats.Nonetheless,how Antarctic water masses influence ciliates,one of the most common groups of protozoa in polar regions,remains largely unknown.The present study investigated how the ciliate communities are affected by com-plex Southern Ocean currents by analyzing the diversity distributions,community assembly mechanisms,and co-occurrence networks of ciliates across three distinct water masses in the Scotia Sea.The findings reveal that the hydrography of the Scotia Sea significantly affects the spatial patterns of planktonic ciliates,primarily through the combination of temperature,salinity,and depth.In contract to surface waters(Antarctic Surface Water and Antarctic Circumpolar Current),ciliates inhab-iting deep waters(Circumpolar Deep Water)exhibit stronger and more direct correlations with the environment parameters,alongside greater network stability.Community assembly in surface and deep-water masses is governed by stochastic and deterministic processes,respectively.Compared to other Antarctic regions documented in previous studies,the Scotia Sea demonstrated the lowest alpha diversity indices for ciliates while harboring the highest number of endemic species.A detailed re-evaluation of Antarctic ciliate community structure in the Antarctic from prior research offers valuable insights into how dynamic ocean currents shape the ecological dynamics of ciliate communities,thus providing a broader understanding of the environmental changes impacting polar marine ecosystems.
基金financially supported by the Special Project on National Science and Technology Basic Resources Investigation of China (2021FY100705)Leading Plan Project of Academic Team of Minzu University of China (2024XSYL04)the Second Tibetan Plateau Scientific Expedition and Research (STEP) Program (2019QZKK040104, 2019QZKK0302)。
文摘Soil microbes play a critical role in maintaining the health and stability of these ecosystems. However, the ecological assembly processes of soil microbial communities remain poorly understood. This study explores the changes in ecological components across original and degraded patches of alpine meadows in Sanjiangyuan National Park and analyzed soil microbial community structure using high-throughput sequencing techniques. Results showed that alpine meadows degradation increased vegetation species diversity, significantly reduced aboveground productivity, and made the soil more barren and alkaline. Although the dominant phyla of soil microorganisms were similar across different degradation states, degradation significantly increased the relative abundance of oligotrophic bacteria and decreased the relative abundance of dominant fungi. Additionally, microbial communities exhibited significant β-diversity. Degradation also led to an increase in microbial α-diversity, heightened microbial taxa competition and a more complex microbial co-occurrence network. However, vegetation-soil variables explained only a small portion of the variation in soil microbes. Through the study of microbial ecological assembly processes, we found that degradation enhanced the stochastic processes of soil microbial communities, and the changes in soil microbial communities were mainly driven by the variations inherent in the microbes themselves. These findings highlight the complex ecological interactions between above- and belowground components and emphasize the critical role of microbial community dynamics qin mediating ecosystem functions.
基金supported by the National Key Research and Development Program(No.2019YFC0408503)Fund Project of National and Local Joint Engineering Research Center for Biomass Energy Development and Utilization(Harbin Institute of Technology,Project No.2021A004).
文摘Conventional biological treatment usually cannot achieve the same high water quality as advanced treatment when conducted under varied temperatures.Here,satisfactory wastewater treatment efficiency was observed in a microalgae-bacteria consortia(MBC)over a wide temperature range because of the predominance of microalgae.Microalgae contributed more toward wastewater treatment at low temperature because of the unsatisfactory performance of the accompanying bacteria,which experienced cold stress(e.g.,bacterial abundance below 3000 sequences)and executed defensive strategies(e.g.,enrichment of cold-shock proteins).A low abundance of amoA-C and hao indicated that conventional nitrogen removal was replaced through the involvement of microalgae.Diverse heterotrophic bacteria for nitrogen removal were identified at medium and high temperatures,implying this microbial niche treatment contained diverse flexible consortia with temperature variation.Additionally,pathogenic bacteria were eliminated through microalgal photosynthesis.After fitting the neutral community model and calculating the ecological niche,microalgae achieved a maximum niche breadth of 5.21 and the lowest niche overlap of 0.38,while the accompanying bacterial community in the consortia were shaped through deterministic processes.Finally,the maximum energy yield of 87.4 kJ L^(-1)and lipid production of 1.9 g L^(-1)were achieved at medium temperature.Altogether,this study demonstrates that advanced treatment and energy reclamation can be achieved through microalgae-bacteria niche strategies.
