SiO_(2)is the main component of gangue in sinters and a crucial constituent in the formation of the SiO_(2)–Fe_(2)O_(3)–Cao(SFC)system.The non-isothermal crystallization kinetics of the SFC system were investigated ...SiO_(2)is the main component of gangue in sinters and a crucial constituent in the formation of the SiO_(2)–Fe_(2)O_(3)–Cao(SFC)system.The non-isothermal crystallization kinetics of the SFC system were investigated using differential scanning calorimetry.The crystallization process of SFC was studied under different cooling rates(5,10,15,and 20 K/min),and the crystalline phases and microstructures of the SFC crystals were verified through X-ray diffraction and scanning electron microscopy.The results indicate that when the SiO_(2)content is 2 wt.%,increasing the cooling rate promotes the precipitation of CaFe_(2)O_(4)(CF)in the SFC system,thereby inhibiting the precipitation of Ca_(2)Fe_(2)O_(5)(C_(2)F).In contrast to the Cao–Fe_(2)O_(3)(C–F)system,the addition of SiO_(2)does not alter the precipitation mechanisms of C_(2)F and CF.By further adding SiO_(2),the precipitation of Ca_(2)Sio_(4)(C_(2)S)significantly increases.Simultaneously,the Cao content in the liquid phase decreases.This leads to the crystallization process of the CF_(4)S(4 wt.%Sio_(2))system bypassing the precipitation of C_(2)F and directly forming CF and CaFe_(4)O_(7)(CF_(2)).In the case of the CF_(8)S(8 wt.%SiO_(2))system,the crystallization process skips the precipitation of C_(2)F and CF,directly yielding CF_(2).The crystallization process of both CF_(2)S(2 wt.%Sio_(2))and CF is similar,comprising two reaction stages.The Ozawa method was used to calculate the activation energy for the crystallization of C_(2)F and CF as-329 and-419 kJ/mol,respectively.Analysis using the Malek method reveals model functions for both stages.展开更多
Climate change has intensified the frequency and severity of urban droughts,exposing urban green spaces to abrupt and extreme water shortage that disrupts plant-microbe interactions and microbial multifunctionality.Un...Climate change has intensified the frequency and severity of urban droughts,exposing urban green spaces to abrupt and extreme water shortage that disrupts plant-microbe interactions and microbial multifunctionality.Understanding how rhizosphere and phyllosphere microbial communities respond to drought and how these shifts influence urban microbial functions is crucial for developing strategies to enhance the resilience of urban ecosystems under climate change.In this study,we conducted microcosm experiments simulating four drought intensities,integrating omics technologies with soil enzyme stoichiometry to investigate the effects of drought on microbial communities associated with Zoysia japonica(Steud)and urban microbial multifunctionality.Our results demonstrate that drought intensities significantly altered the compositions of bacterial and fungal communities in both the rhizosphere and phyllosphere.Moreover,drought enhanced microbial multifunctionality by significantly affecting 21 microbial functional potentials,including carbon fixation and denitrification.Although urban microbial multifunctionality largely returned to the control level after rehydration,five functions remained altered,including phyllosphere organic nitrogen mineralization and soil polyphenol oxidase activity.Biotic factors,particularly rhizosphere bacteria and fungi,directly influenced microbial multifunctionality during drought,whereas abiotic factors,such as electrical conductivity,dissolved organic carbon,and ammonium-nitrogen(NH_(4)^(+)-N),had indirect effects.After rehydration,abiotic factors,especially pH and NH_(4)^(+)-N,emerged as the main direct drivers.These findings underscore a shift from biotic to abiotic regulation of urban microbial multifunctionality across drought and rehydration,emphasizing the vital role of microbial communities in ecosystem resilience and the need to consider both biotic and abiotic factors in urban drought management.展开更多
Dear Editor, Cities are among the most drought-prone areas globally. Meanwhile, the Chinese urban coastal areas face frequent flash droughts and also heightened flood risks, characterized by extreme precipitation and ...Dear Editor, Cities are among the most drought-prone areas globally. Meanwhile, the Chinese urban coastal areas face frequent flash droughts and also heightened flood risks, characterized by extreme precipitation and heatwave events exacerbated by tropical intraseasonal oscillations and meandering subtropical currents(Lai et al., 2024;Yuan et al., 2023).展开更多
Earthworm gut microbiome can significantly influence soil microbial community and functions.However,how earthworms affect the abundant,intermediate,and rare soil bacterial taxa and subsequently regulate soil multifunc...Earthworm gut microbiome can significantly influence soil microbial community and functions.However,how earthworms affect the abundant,intermediate,and rare soil bacterial taxa and subsequently regulate soil multifunctionality remains poorly understood.In this study,we investigated bacteria composition and functional gene traits with and without earthworm addition in low-nutrient soil.Our results show that earthworm addition enhanced soil multifunctionality,including organic carbon,nitrogen,and phosphorus mineralization.Compared to other groups,abundant taxa in earthworm-treated soil exhibited higher 16S rRNA operon copy numbers,copiotroph/oligotroph ratios,niche width,and network efficiency,suggesting a greater competitive capacity for resource acquisition.We identified a core set of persistent abundant taxa genera(11 genera)in earthworm-treated soil,which persisted throughout the incubation period,and were notably dominant among abundant taxa in the earthworm gut(67.1%−79.2%).Furthermore,structural equation modeling revealed that gut-associated abundant taxa strongly influenced the composition of soil abundant taxa and persistent core abundant taxa genera,which in turn increased soil r-strategists and enhanced multifunctionality.Overall,our findings provide new insights into the ecological strategies of different soil taxa in response to earthworm addition and highlight the role of earthworm gut microbiome in adapting to nutrient-poor environments.展开更多
Loss of biodiversity is a major threat to the ecosystem processes upon which society depends.Natural ecosystems differ in their resistance to invasion by alien species,and this resistance can depend on the diversity i...Loss of biodiversity is a major threat to the ecosystem processes upon which society depends.Natural ecosystems differ in their resistance to invasion by alien species,and this resistance can depend on the diversity in the system.Little is known,however,about the barriers that microbial diversity provides against microbial invasion.The increasing prevalence of antibioticresistant bacteria is a serious threat to public health in the 21st century.We explored the consequences of the reduction in soil microbial diversity for the dissemination of antibiotic resistance.The relationship between this diversity and the invasion of antibiotic resistance was investigated using a dilution-to-extinction approach coupled with high-capacity quantitative PCR.Microbial diversity was negatively correlated with the abundance of antibiotic-resistance genes,and this correlation was maintained after accounting for other potential drivers such as incubation time and microbial abundance.Our results demonstrate that high microbial diversity can act as a biological barrier resist the spread of antibiotic resistance.These results fill a critical gap in our understanding of the role of soil microbial diversity in the health of ecosystems.展开更多
The microbiome contributes to multiple ecosystem functions and services through its interactions with a complex environment and other organisms.To date,however,most microbiome studies have been carried out on individu...The microbiome contributes to multiple ecosystem functions and services through its interactions with a complex environment and other organisms.To date,however,most microbiome studies have been carried out on individual hosts or particular environmental compartments.This greatly limits a comprehensive understanding of the processes and functions performed by the microbiome and its dynamics at an ecosystem level.We propose that the theory and tools of ecosystem ecology be used to investigate the connectivity of microorganisms and their interactions with the biotic and abiotic environment within entire ecosystems and to examine their contributions to ecosystem services.Impacts of natural and anthropogenic stressors on ecosystems will likely cause cascading effects on the microbiome and lead to unpredictable outcomes,such as outbreaks of emerging infectious diseases or changes in mutualistic interactions.Despite enormous advances in microbial ecology,we are yet to study microbiomes of ecosystems as a whole.Doing so would establish a new framework for microbiome study:Ecosystem Microbiome Science.The advent and application of molecular and genomic technologies,together with data science and modeling,will accelerate progress in this field.展开更多
Antibiotic resistance genes(ARGs)and antibiotic resistant bacteria(ARB)in the environment pose serious threats to environmental security and public health.There is an urgent need for methods to specifically and effect...Antibiotic resistance genes(ARGs)and antibiotic resistant bacteria(ARB)in the environment pose serious threats to environmental security and public health.There is an urgent need for methods to specifically and effectively control environmental pollution or pathogen infection associated with ARGs and ARB.This review aims to provide an overview of methods abating the prevalence and spread of ARGs and ARB from species to community level.At the species level,species-specific technologies,such as nanoparticle-,photosensitizer-,CRISPR-Cas-,and phage-related technology can be utilized to clear a particular class of ARGs or ARB,and in combination with low-dose antibiotics,a higher removal efficiency can be achieved.Moreover,the combination of antibiotics can be used to reverse microbial resistance and treat recurrent antibiotic resistant pathogen infections.At the community level,community-specific strategies,such as biochar,hyperthermophilic compost,and fecal microbiota transplantation can eradicate most types of ARGs or ARB in one shot,reducing the probability of resistance development.Though some progress has been made to eliminate ARGs and ARB in disease treatment or decontamination scenarios,further research is still needed to elucidate their mechanisms of action and scopes of application,and efforts should be made to explore novel strategies to counter the prevalence of antibiotic resistance.展开更多
基金This work was supported by the National Natural Science Foundation of China(52204331)Natural Science Foundation of Anhui Province Youth Project(2208085QE145)the Open Project Program of Key Laboratory of Metallurgical Emission Reduction&Resources Recycling(Anhui University of Technology),Ministry of Education(JKF20–03).
文摘SiO_(2)is the main component of gangue in sinters and a crucial constituent in the formation of the SiO_(2)–Fe_(2)O_(3)–Cao(SFC)system.The non-isothermal crystallization kinetics of the SFC system were investigated using differential scanning calorimetry.The crystallization process of SFC was studied under different cooling rates(5,10,15,and 20 K/min),and the crystalline phases and microstructures of the SFC crystals were verified through X-ray diffraction and scanning electron microscopy.The results indicate that when the SiO_(2)content is 2 wt.%,increasing the cooling rate promotes the precipitation of CaFe_(2)O_(4)(CF)in the SFC system,thereby inhibiting the precipitation of Ca_(2)Fe_(2)O_(5)(C_(2)F).In contrast to the Cao–Fe_(2)O_(3)(C–F)system,the addition of SiO_(2)does not alter the precipitation mechanisms of C_(2)F and CF.By further adding SiO_(2),the precipitation of Ca_(2)Sio_(4)(C_(2)S)significantly increases.Simultaneously,the Cao content in the liquid phase decreases.This leads to the crystallization process of the CF_(4)S(4 wt.%Sio_(2))system bypassing the precipitation of C_(2)F and directly forming CF and CaFe_(4)O_(7)(CF_(2)).In the case of the CF_(8)S(8 wt.%SiO_(2))system,the crystallization process skips the precipitation of C_(2)F and CF,directly yielding CF_(2).The crystallization process of both CF_(2)S(2 wt.%Sio_(2))and CF is similar,comprising two reaction stages.The Ozawa method was used to calculate the activation energy for the crystallization of C_(2)F and CF as-329 and-419 kJ/mol,respectively.Analysis using the Malek method reveals model functions for both stages.
基金supported by the Natural Science Foundation of Fujian Province(2023J02029)the National Natural Science Foundation of China(42207143)。
文摘Climate change has intensified the frequency and severity of urban droughts,exposing urban green spaces to abrupt and extreme water shortage that disrupts plant-microbe interactions and microbial multifunctionality.Understanding how rhizosphere and phyllosphere microbial communities respond to drought and how these shifts influence urban microbial functions is crucial for developing strategies to enhance the resilience of urban ecosystems under climate change.In this study,we conducted microcosm experiments simulating four drought intensities,integrating omics technologies with soil enzyme stoichiometry to investigate the effects of drought on microbial communities associated with Zoysia japonica(Steud)and urban microbial multifunctionality.Our results demonstrate that drought intensities significantly altered the compositions of bacterial and fungal communities in both the rhizosphere and phyllosphere.Moreover,drought enhanced microbial multifunctionality by significantly affecting 21 microbial functional potentials,including carbon fixation and denitrification.Although urban microbial multifunctionality largely returned to the control level after rehydration,five functions remained altered,including phyllosphere organic nitrogen mineralization and soil polyphenol oxidase activity.Biotic factors,particularly rhizosphere bacteria and fungi,directly influenced microbial multifunctionality during drought,whereas abiotic factors,such as electrical conductivity,dissolved organic carbon,and ammonium-nitrogen(NH_(4)^(+)-N),had indirect effects.After rehydration,abiotic factors,especially pH and NH_(4)^(+)-N,emerged as the main direct drivers.These findings underscore a shift from biotic to abiotic regulation of urban microbial multifunctionality across drought and rehydration,emphasizing the vital role of microbial communities in ecosystem resilience and the need to consider both biotic and abiotic factors in urban drought management.
基金supported by the Natural Science Foundation of Fujian Province (2023J02029)Ningbo Public Welfare Project (2022S117)Ningbo S&T Project (2021-DST-004)。
文摘Dear Editor, Cities are among the most drought-prone areas globally. Meanwhile, the Chinese urban coastal areas face frequent flash droughts and also heightened flood risks, characterized by extreme precipitation and heatwave events exacerbated by tropical intraseasonal oscillations and meandering subtropical currents(Lai et al., 2024;Yuan et al., 2023).
基金supported by the National Natural Science Foundation of China(Grant Nos.42077088,42407447)Zhejiang Province“Agriculture,Rural Areas,Rural People and Nine Institutions”Science and Technology Collaboration Program,China Postdoctoral Science Foundation(Certificate Number:2023M743418)the Key Project of Science and Technology Innovation in Ningbo City(Grant No.2022Z169).
文摘Earthworm gut microbiome can significantly influence soil microbial community and functions.However,how earthworms affect the abundant,intermediate,and rare soil bacterial taxa and subsequently regulate soil multifunctionality remains poorly understood.In this study,we investigated bacteria composition and functional gene traits with and without earthworm addition in low-nutrient soil.Our results show that earthworm addition enhanced soil multifunctionality,including organic carbon,nitrogen,and phosphorus mineralization.Compared to other groups,abundant taxa in earthworm-treated soil exhibited higher 16S rRNA operon copy numbers,copiotroph/oligotroph ratios,niche width,and network efficiency,suggesting a greater competitive capacity for resource acquisition.We identified a core set of persistent abundant taxa genera(11 genera)in earthworm-treated soil,which persisted throughout the incubation period,and were notably dominant among abundant taxa in the earthworm gut(67.1%−79.2%).Furthermore,structural equation modeling revealed that gut-associated abundant taxa strongly influenced the composition of soil abundant taxa and persistent core abundant taxa genera,which in turn increased soil r-strategists and enhanced multifunctionality.Overall,our findings provide new insights into the ecological strategies of different soil taxa in response to earthworm addition and highlight the role of earthworm gut microbiome in adapting to nutrient-poor environments.
基金supported by the National Natural Science Foundation of China(21210008,41571130063)Strategic Priority Research Program of Chinese Academy of Sciences(XDB15020402)European Research Council from Synergy grant ERC-2013-SyG-610028“IMBALANCE-P.”。
文摘Loss of biodiversity is a major threat to the ecosystem processes upon which society depends.Natural ecosystems differ in their resistance to invasion by alien species,and this resistance can depend on the diversity in the system.Little is known,however,about the barriers that microbial diversity provides against microbial invasion.The increasing prevalence of antibioticresistant bacteria is a serious threat to public health in the 21st century.We explored the consequences of the reduction in soil microbial diversity for the dissemination of antibiotic resistance.The relationship between this diversity and the invasion of antibiotic resistance was investigated using a dilution-to-extinction approach coupled with high-capacity quantitative PCR.Microbial diversity was negatively correlated with the abundance of antibiotic-resistance genes,and this correlation was maintained after accounting for other potential drivers such as incubation time and microbial abundance.Our results demonstrate that high microbial diversity can act as a biological barrier resist the spread of antibiotic resistance.These results fill a critical gap in our understanding of the role of soil microbial diversity in the health of ecosystems.
基金supported financially by the National Natural Science Foundation of China(Nos.21936006 and 42021005)the Alliance of International Science Organizations(Grant No.ANSO-PA-2020-18).
文摘The microbiome contributes to multiple ecosystem functions and services through its interactions with a complex environment and other organisms.To date,however,most microbiome studies have been carried out on individual hosts or particular environmental compartments.This greatly limits a comprehensive understanding of the processes and functions performed by the microbiome and its dynamics at an ecosystem level.We propose that the theory and tools of ecosystem ecology be used to investigate the connectivity of microorganisms and their interactions with the biotic and abiotic environment within entire ecosystems and to examine their contributions to ecosystem services.Impacts of natural and anthropogenic stressors on ecosystems will likely cause cascading effects on the microbiome and lead to unpredictable outcomes,such as outbreaks of emerging infectious diseases or changes in mutualistic interactions.Despite enormous advances in microbial ecology,we are yet to study microbiomes of ecosystems as a whole.Doing so would establish a new framework for microbiome study:Ecosystem Microbiome Science.The advent and application of molecular and genomic technologies,together with data science and modeling,will accelerate progress in this field.
基金supported by the National Key Research and Development Plan(Grant No.2020YFC1806902)the National Natural Science Foundation of China(Grant No.42161134002).
文摘Antibiotic resistance genes(ARGs)and antibiotic resistant bacteria(ARB)in the environment pose serious threats to environmental security and public health.There is an urgent need for methods to specifically and effectively control environmental pollution or pathogen infection associated with ARGs and ARB.This review aims to provide an overview of methods abating the prevalence and spread of ARGs and ARB from species to community level.At the species level,species-specific technologies,such as nanoparticle-,photosensitizer-,CRISPR-Cas-,and phage-related technology can be utilized to clear a particular class of ARGs or ARB,and in combination with low-dose antibiotics,a higher removal efficiency can be achieved.Moreover,the combination of antibiotics can be used to reverse microbial resistance and treat recurrent antibiotic resistant pathogen infections.At the community level,community-specific strategies,such as biochar,hyperthermophilic compost,and fecal microbiota transplantation can eradicate most types of ARGs or ARB in one shot,reducing the probability of resistance development.Though some progress has been made to eliminate ARGs and ARB in disease treatment or decontamination scenarios,further research is still needed to elucidate their mechanisms of action and scopes of application,and efforts should be made to explore novel strategies to counter the prevalence of antibiotic resistance.
