In recent decades,meromictic ponds attract the attention of researchers in different directions,because here the character of the physical,chemical and biological processes differ from those of typical mixing waters(K...In recent decades,meromictic ponds attract the attention of researchers in different directions,because here the character of the physical,chemical and biological processes differ from those of typical mixing waters(Kuznetsov,1970;Hutchinson,1969).In Transbaikalia widely distributed soda and salt lakes with different salinity.Notable among them is Lake Doroninskoye,which has a pronounced stratification for a展开更多
Nicosulfuron(NSR),a sulfonylurea herbicide,readily infiltrates water bodies,potentially compromising aquatic ecosystems and human health.In this study,bacteria consortium YM2 was isolated and cultivated from pesticide...Nicosulfuron(NSR),a sulfonylurea herbicide,readily infiltrates water bodies,potentially compromising aquatic ecosystems and human health.In this study,bacteria consortium YM2 was isolated and cultivated from pesticide plant active sludge for NSR wastewater bioremediation.Response surface methodology analysis demonstrated that under optimal cultivation conditions(9.41 g L^(-1)maltodextrin,21.37 g L^(-1)yeast extract,and 12.45 g L^(-1)NaCl),the YM2 bacteria consortium achieved 97.49%NSR degradation within 4 d.Optimal degradation parameters were established at 30℃,pH 6.0,1%inoculum,and 20 mg L^(-1)initial NSR concentration.The degradation system demonstrated resistance to heavy metal ions including Cd^(2+),Pb^(2+),Ni^(2+),and Zn^(2+),with degradation primarily occurring through bacterial extracellular enzymes(92.17%).During the degradation process,reactive oxygen species,oxidative stress,cell membrane permeability,cell surface hydrophobicity,and apoptosis rate exhibited initial increases followed by decreases.Additionally,bioflm formation-related genes luxS,waaE,spo0A,and wza showed temporal and concentration-dependent expression patterns.NSR concentrations in wastewater and soil were reduced to 1.92 and 2.72 mg L^(-1),respectively.In a simulated wastewater treatment unit with a 12-h hydraulic retention time,YM2 achieved 84.55%NSR degradation after 10 d.These fndings provide a theoretical foundation for microbial remediation of NSR contamination.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
Forest ecosystems function as the largest carbon(C)sink in terrestrial ecosystems,and nearly half of the C in forest ecosystems is stored in forest soils.However,the patterns of two main fractions of soil organic C,pa...Forest ecosystems function as the largest carbon(C)sink in terrestrial ecosystems,and nearly half of the C in forest ecosystems is stored in forest soils.However,the patterns of two main fractions of soil organic C,particulate organic C(POC)and mineral-associated organic C(MAOC),across various types of forest ecosystems remain unclear.In this study,soil samples were collected from depths of 0–100 cm at eight sites located between 18°and 48°north latitude in eastern China.The soil samples were then separated into particulate organic matter(POM)and mineral-associated organic matter(MAOM)based on particle size to analyze the distribution of C within each fraction.The results showed that the C stored as POC increased with latitude and decreased with soil depth.Specifically,28.1%,38.5%and 55.6%of C was stored as POC in the topsoil(0–30 cm)of tropical,subtropical and temperate forests,respectively,while 24.0%,24.3%and 38.9%of C was stored as POC in the subsoil(30–100 cm)of the corresponding forests,respectively.MAOC experienced a higher degree of microbial processing(indicated by differences in δ^(13)C,δ^(15)N and C:N between POM and MAOM)than POC,with a more pronounced difference in microbial processing between MAOC and POC at lower latitudes than at higher latitudes.These findings contribute to a comprehensive understanding of the characteristics of forest SOC and offer potential strategies for enhancing forest C sequestration.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
基金supported by Integration projects of the Presidium of SB RAS№5,56,94
文摘In recent decades,meromictic ponds attract the attention of researchers in different directions,because here the character of the physical,chemical and biological processes differ from those of typical mixing waters(Kuznetsov,1970;Hutchinson,1969).In Transbaikalia widely distributed soda and salt lakes with different salinity.Notable among them is Lake Doroninskoye,which has a pronounced stratification for a
基金financially supported by the Jilin Province Development and Reform Commission(Innovation Capacity Building)Project,China(20231036-3)the Key R&D Project of the Science and Technology Development Plan of Jilin,China(20230203014SF)。
文摘Nicosulfuron(NSR),a sulfonylurea herbicide,readily infiltrates water bodies,potentially compromising aquatic ecosystems and human health.In this study,bacteria consortium YM2 was isolated and cultivated from pesticide plant active sludge for NSR wastewater bioremediation.Response surface methodology analysis demonstrated that under optimal cultivation conditions(9.41 g L^(-1)maltodextrin,21.37 g L^(-1)yeast extract,and 12.45 g L^(-1)NaCl),the YM2 bacteria consortium achieved 97.49%NSR degradation within 4 d.Optimal degradation parameters were established at 30℃,pH 6.0,1%inoculum,and 20 mg L^(-1)initial NSR concentration.The degradation system demonstrated resistance to heavy metal ions including Cd^(2+),Pb^(2+),Ni^(2+),and Zn^(2+),with degradation primarily occurring through bacterial extracellular enzymes(92.17%).During the degradation process,reactive oxygen species,oxidative stress,cell membrane permeability,cell surface hydrophobicity,and apoptosis rate exhibited initial increases followed by decreases.Additionally,bioflm formation-related genes luxS,waaE,spo0A,and wza showed temporal and concentration-dependent expression patterns.NSR concentrations in wastewater and soil were reduced to 1.92 and 2.72 mg L^(-1),respectively.In a simulated wastewater treatment unit with a 12-h hydraulic retention time,YM2 achieved 84.55%NSR degradation after 10 d.These fndings provide a theoretical foundation for microbial remediation of NSR contamination.
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financially supported by the National Natural Science Foundation of China(Nos.42141006,32425038 and 31988102).
文摘Forest ecosystems function as the largest carbon(C)sink in terrestrial ecosystems,and nearly half of the C in forest ecosystems is stored in forest soils.However,the patterns of two main fractions of soil organic C,particulate organic C(POC)and mineral-associated organic C(MAOC),across various types of forest ecosystems remain unclear.In this study,soil samples were collected from depths of 0–100 cm at eight sites located between 18°and 48°north latitude in eastern China.The soil samples were then separated into particulate organic matter(POM)and mineral-associated organic matter(MAOM)based on particle size to analyze the distribution of C within each fraction.The results showed that the C stored as POC increased with latitude and decreased with soil depth.Specifically,28.1%,38.5%and 55.6%of C was stored as POC in the topsoil(0–30 cm)of tropical,subtropical and temperate forests,respectively,while 24.0%,24.3%and 38.9%of C was stored as POC in the subsoil(30–100 cm)of the corresponding forests,respectively.MAOC experienced a higher degree of microbial processing(indicated by differences in δ^(13)C,δ^(15)N and C:N between POM and MAOM)than POC,with a more pronounced difference in microbial processing between MAOC and POC at lower latitudes than at higher latitudes.These findings contribute to a comprehensive understanding of the characteristics of forest SOC and offer potential strategies for enhancing forest C sequestration.
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.
