Despite recent interest in microbial diversity and community structure of lakes across various spatial scales, a global biogeographic distribution pattern and its controlling factors have not been fully disclosed. Her...Despite recent interest in microbial diversity and community structure of lakes across various spatial scales, a global biogeographic distribution pattern and its controlling factors have not been fully disclosed. Here, we compiled and analyzed 88,334,735 environmental 16S rRNA sequences from 431 lakes across a wide range of geographical distance and environmental conditions(in particular, salinity, 0–373.3 gL^–1). Our results showed that lake sediments inhabit significantly(ANOVA: P<0.001) more diverse microbial communities than lake waters. Non-metric dimensional scaling(NMDS) ordinations indicated that microbial community compositions differed distinctly among sample types(freshwater vs. saline, water vs. sediment) and geographic locations. Mantel and partial Mantel tests showed that microbial community composition in lake water was significantly(P=0.001) correlated with geographic distance, salinity, and pH. Statistical analyses based on neutral community and null models indicated that stochastic processes may play predominant roles in shaping the microbial biogeographic distribution patterns in the studied global lake waters. The dispersal-related stochasticity(e.g., homogenizing dispersal) exhibited a stronger influence on the distribution of microbial community in freshwater lakes than in saline lakes. Overall, this work expands our understanding of the impact of geographic distance, environmental conditions, and stochastic processes on microbial distribution in global lakes.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
Assembly processes of prokaryotic and microeukaryotic community is an important issue in microbial ecology.However,unclear remains about the relative contribution of deterministic and stochastic processes to the shapi...Assembly processes of prokaryotic and microeukaryotic community is an important issue in microbial ecology.However,unclear remains about the relative contribution of deterministic and stochastic processes to the shaping of prokaryotic and microeukaryotic communities in saline lake water.Here,we systematically investigated the assembly processes governing the prokaryotic and microeukaryotic communities in Qinghai Lake with the use of Illumina sequencing and a null model.The results showed that both deterministic and stochastic processes play vital roles in shaping the assemblies of prokaryotic and microeukaryotic communities,in which stochastic processes appeared to dominate(> 70%).Prokaryotic communities were mainly governed by non-dominant processes(60.4%),followed by homogeneous selection(15.8%),variable selection(13.6%) and dispersal limitation(10.2%),whereas microeukaryotes were strongly driven by non-dominant processes(68.9%),followed by variable selection(23.6%) and homogenizing dispersal(6.3%).In terms of variable selection,nutrients(e.g.,ammonium,dissolved inorganic carbon,dissolved organic carbon and total nitrogen) were the major factors influencing prokaryotic and microeukaryotic community structures.In summary,prokaryotes and microeukaryotes can be predominantly structured by different assembly mechanisms,in which stochasticity is stronger than deterministic processes.This finding helps to better comprehend the assembly of prokaryotic and eukaryotic communities in saline lakes.展开更多
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
基金supported by grants from the National Natural Science Foundation of China (91751206, 41521001, 41602346, 41572328, 41630103)the 111 Program (State Administration of Foreign Experts Affairs & the Ministry of Education of China, grant B18049)+1 种基金Fundamental Research Funds for the Central Universities, China University of Geosciences (Wuhan)State Key Laboratory of Biogeology and Environmental Geology, CUG (GBL11805)
文摘Despite recent interest in microbial diversity and community structure of lakes across various spatial scales, a global biogeographic distribution pattern and its controlling factors have not been fully disclosed. Here, we compiled and analyzed 88,334,735 environmental 16S rRNA sequences from 431 lakes across a wide range of geographical distance and environmental conditions(in particular, salinity, 0–373.3 gL^–1). Our results showed that lake sediments inhabit significantly(ANOVA: P<0.001) more diverse microbial communities than lake waters. Non-metric dimensional scaling(NMDS) ordinations indicated that microbial community compositions differed distinctly among sample types(freshwater vs. saline, water vs. sediment) and geographic locations. Mantel and partial Mantel tests showed that microbial community composition in lake water was significantly(P=0.001) correlated with geographic distance, salinity, and pH. Statistical analyses based on neutral community and null models indicated that stochastic processes may play predominant roles in shaping the microbial biogeographic distribution patterns in the studied global lake waters. The dispersal-related stochasticity(e.g., homogenizing dispersal) exhibited a stronger influence on the distribution of microbial community in freshwater lakes than in saline lakes. Overall, this work expands our understanding of the impact of geographic distance, environmental conditions, and stochastic processes on microbial distribution in global lakes.
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 grants from the National Natural Science Foundation of China (Nos.92251304 and 41972317)the 111 Program (State Administration of Foreign Experts Affairs&the Ministry of Education of China,No.B18049)+2 种基金the Second Tibetan Plateau Scientific Expedition and Research Program (STEP)(No.2019QZKK0805)the Science and Technology Plan Project of Qinghai Province (No.2022-ZJ-Y08)State Key Laboratory of Biogeology and Environmental Geology,CUG (No.GBL11805)。
文摘Assembly processes of prokaryotic and microeukaryotic community is an important issue in microbial ecology.However,unclear remains about the relative contribution of deterministic and stochastic processes to the shaping of prokaryotic and microeukaryotic communities in saline lake water.Here,we systematically investigated the assembly processes governing the prokaryotic and microeukaryotic communities in Qinghai Lake with the use of Illumina sequencing and a null model.The results showed that both deterministic and stochastic processes play vital roles in shaping the assemblies of prokaryotic and microeukaryotic communities,in which stochastic processes appeared to dominate(> 70%).Prokaryotic communities were mainly governed by non-dominant processes(60.4%),followed by homogeneous selection(15.8%),variable selection(13.6%) and dispersal limitation(10.2%),whereas microeukaryotes were strongly driven by non-dominant processes(68.9%),followed by variable selection(23.6%) and homogenizing dispersal(6.3%).In terms of variable selection,nutrients(e.g.,ammonium,dissolved inorganic carbon,dissolved organic carbon and total nitrogen) were the major factors influencing prokaryotic and microeukaryotic community structures.In summary,prokaryotes and microeukaryotes can be predominantly structured by different assembly mechanisms,in which stochasticity is stronger than deterministic processes.This finding helps to better comprehend the assembly of prokaryotic and eukaryotic communities in saline lakes.
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
