[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic me...[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic mechanism of alien plants invasion.[Result]Most of the invasive plants have not been explicitly defined and their effective control methods not brought forward.[Conclusion]Overrun of alien invasive plants depends on whether the niche of a species could be continuously met at spatial level.Based on this we put forward corresponding control measures,proposed an assumption to establish a cylinder-network model and discussed the definition of alien invasive plants.展开更多
Anchovy （Engraulis aponicus）, a small pelagic fish and food of other economic fishes, is a key species in the Yellow Sea ecosystem. Understanding the mechanisms of its recruitment and biomass variation is important ...Anchovy （Engraulis aponicus）, a small pelagic fish and food of other economic fishes, is a key species in the Yellow Sea ecosystem. Understanding the mechanisms of its recruitment and biomass variation is important for the prediction and management of fishery resources. Coupled with a hydrodynamic model （POM） and a lower trophic level ecosystem model （NEMURO）, an individual-based model of anchovy is developed to study the influence of physical environment on anchovy＇s biomass variation, Seasonal variations of circulation, water temperature and mix-layer depth from POM are used as external forcing for NEMURO and the anchovy model. Biomasses of large zooplankton and predatory zooplankton which anchovy feeds on are output from NEMURO and are controlled by the consumption of anchovy on them. Survival fitness theory related to temperature and food is used to determine the swimming action of anchovy in the model. The simulation results agree well with observations and elucidate the influence of temperature in over-wintering migration and food in feeding migration.展开更多
Interconnected river system networks is a national water conservancy strategy in China and focus of research. Here we discuss the classification system, material and energy exchange between rivers and lakes, various d...Interconnected river system networks is a national water conservancy strategy in China and focus of research. Here we discuss the classification system, material and energy exchange between rivers and lakes, various dynamic flows and ecological functions of river-lake interconnected relationships. We then propose a novel method for the health assessment of river systems based on interconnected water system networks. In a healthy river system there is ＂material and energy exchange＂ and it is the first and foremost relationship of material and energy exchange between rivers and lakes. There are unobstructed various ＂flows＂ between rivers and lakes including material flows （water, dissolved substances, sediments, organisms and contaminants）, energy flows （water levels, flow and flow velocity）, information flows （information generated with water flows, organisms and human activities） and value flows （shipping, power generation, drinking and irrigation）. Under the influences of na- ture and human activity, various flows are connected by river-lake interconnection to carry material and energy exchange between rivers and lakes to achieve river-lake interactions. The material and energy exchange between rivers and lakes become one of the approaches and the direct driving forces of changes in river-lake interconnected relationships. The benignant changes in river-lake interconnected relationship tend to be in relatively steady state and in ideal dynamic balance.展开更多
Germanium based sulfides are potentially attractive as anode material for sodium ion batteries but rarely investigated. Herein, we firstly investigated Na^＋storage properties of pristine Cu2GeS3（PCGS） and found an ...Germanium based sulfides are potentially attractive as anode material for sodium ion batteries but rarely investigated. Herein, we firstly investigated Na^＋storage properties of pristine Cu2GeS3（PCGS） and found an effective strategy to improve its performance by a single lithiation/delithiation cycle obtaining ultrafine nanoparticle copper germanium sulfide（NCGS）. The lithiation/delithiation process leads to the formation of a stable Li-containing solid electrolyte interphase film and a significant improvement of sodiation kinetics. Therefore, the NCGS anode delivers favorable capacity retention and better rate capability compared with that of a PCGS whether in the half cell or in the full cell,showing great promise for energy storage application.展开更多
Aims Litterfall at a global scale is affected by climate,edaphic features and vegetation structure,with litter production increasing from grasslands to forests following the rise in standing biomass.However,at landsca...Aims Litterfall at a global scale is affected by climate,edaphic features and vegetation structure,with litter production increasing from grasslands to forests following the rise in standing biomass.However,at landscape scales,the same relationship between litter production and vegetation structure has rarely been studied and comparisons of litterfall patterns between adjacent,structurally distinct communities are lacking.Here,we use a standardized methodology to describe the structural differences among four savanna physiognomies and analyze their relationship with changes in litterfall across the Cerrado.Methods We evaluated the woody vegetation structure and composition in 48 sites,equally distributed across four physiognomies and monitored the monthly litter production from April 2014 to March 2015.Important Findings Results showed that the density,basal area,cylindrical volume and aboveground biomass of woody vegetation differ among physiognomies,increasing consistently from cerrado ralo,cerrado típico,cerrado denso and cerradão.Indeed,we found a strong and positive relationship between aboveground biomass and annual litter production,with litter yield increasing from 0.9 to 8.4 Mg ha^(−1)across different physiognomies,following the increment in vegetation structure.Monthly production was seasonal and similar among vegetation types,increasing during the dry season.Leaves comprised the dominant fraction(approx.85%)and litterfall seasonality primarily resulted from the concentration of leaf shedding during dry months.However,the temporal pattern of litterfall throughout the year showed a gradual reduction in the seasonality from open to closed vegetation types,likely following the decrease of deciduous species abundance in the plant community.Our results showed that changes in vegetation structure may affect spatial and temporal litterfall patterns in different physiognomies,which co-occur across the Cerrado landscape,with potential implications for the overall functioning of this ecosystem.Moreover,these findings highlight the use of standardized methods as essential to correctly compare litterfall patterns among different environments.展开更多
基金Supported by Joint Research Fund from National Natural Science Foundation of China(NSFC)-Yunnan Province(U0933601)Students Research Fund from Southwest Forestry University(1001)~~
文摘[Objective]This study was to reveal the essence of mechanism about how the alien invasive plants spread.[Method]Species niche and material/energy flow were used as basic research indicators to analyze the intrinsic mechanism of alien plants invasion.[Result]Most of the invasive plants have not been explicitly defined and their effective control methods not brought forward.[Conclusion]Overrun of alien invasive plants depends on whether the niche of a species could be continuously met at spatial level.Based on this we put forward corresponding control measures,proposed an assumption to establish a cylinder-network model and discussed the definition of alien invasive plants.
基金supported by the National Natural Science Foundation of China (Grant No. 40830854)the National Basic Research Program of China (Grant No.2011CB403606)
文摘Anchovy （Engraulis aponicus）, a small pelagic fish and food of other economic fishes, is a key species in the Yellow Sea ecosystem. Understanding the mechanisms of its recruitment and biomass variation is important for the prediction and management of fishery resources. Coupled with a hydrodynamic model （POM） and a lower trophic level ecosystem model （NEMURO）, an individual-based model of anchovy is developed to study the influence of physical environment on anchovy＇s biomass variation, Seasonal variations of circulation, water temperature and mix-layer depth from POM are used as external forcing for NEMURO and the anchovy model. Biomasses of large zooplankton and predatory zooplankton which anchovy feeds on are output from NEMURO and are controlled by the consumption of anchovy on them. Survival fitness theory related to temperature and food is used to determine the swimming action of anchovy in the model. The simulation results agree well with observations and elucidate the influence of temperature in over-wintering migration and food in feeding migration.
基金National Natural Science Foundation of China(41361003)Science and Technology Project in Jiangxi Province Department of Education(GJJ14733)
文摘Interconnected river system networks is a national water conservancy strategy in China and focus of research. Here we discuss the classification system, material and energy exchange between rivers and lakes, various dynamic flows and ecological functions of river-lake interconnected relationships. We then propose a novel method for the health assessment of river systems based on interconnected water system networks. In a healthy river system there is ＂material and energy exchange＂ and it is the first and foremost relationship of material and energy exchange between rivers and lakes. There are unobstructed various ＂flows＂ between rivers and lakes including material flows （water, dissolved substances, sediments, organisms and contaminants）, energy flows （water levels, flow and flow velocity）, information flows （information generated with water flows, organisms and human activities） and value flows （shipping, power generation, drinking and irrigation）. Under the influences of na- ture and human activity, various flows are connected by river-lake interconnection to carry material and energy exchange between rivers and lakes to achieve river-lake interactions. The material and energy exchange between rivers and lakes become one of the approaches and the direct driving forces of changes in river-lake interconnected relationships. The benignant changes in river-lake interconnected relationship tend to be in relatively steady state and in ideal dynamic balance.
基金National Natural Science Foundation of China (51502319)Shandong Provincial Natural Science Foundation (BS2015CL014)the Think-Tank Mutual Fund of Qingdao Energy Storage Industry Scientific Research and Qingdao Key Lab of Solar Energy Utilization and Energy Storage Technology
文摘Germanium based sulfides are potentially attractive as anode material for sodium ion batteries but rarely investigated. Herein, we firstly investigated Na^＋storage properties of pristine Cu2GeS3（PCGS） and found an effective strategy to improve its performance by a single lithiation/delithiation cycle obtaining ultrafine nanoparticle copper germanium sulfide（NCGS）. The lithiation/delithiation process leads to the formation of a stable Li-containing solid electrolyte interphase film and a significant improvement of sodiation kinetics. Therefore, the NCGS anode delivers favorable capacity retention and better rate capability compared with that of a PCGS whether in the half cell or in the full cell,showing great promise for energy storage application.
基金supported by the Brazilian National Research Council-CNPq(Long Term Ecological Projects-PELD,grant no.403733/2012-0 and 441225/2016-0).
文摘Aims Litterfall at a global scale is affected by climate,edaphic features and vegetation structure,with litter production increasing from grasslands to forests following the rise in standing biomass.However,at landscape scales,the same relationship between litter production and vegetation structure has rarely been studied and comparisons of litterfall patterns between adjacent,structurally distinct communities are lacking.Here,we use a standardized methodology to describe the structural differences among four savanna physiognomies and analyze their relationship with changes in litterfall across the Cerrado.Methods We evaluated the woody vegetation structure and composition in 48 sites,equally distributed across four physiognomies and monitored the monthly litter production from April 2014 to March 2015.Important Findings Results showed that the density,basal area,cylindrical volume and aboveground biomass of woody vegetation differ among physiognomies,increasing consistently from cerrado ralo,cerrado típico,cerrado denso and cerradão.Indeed,we found a strong and positive relationship between aboveground biomass and annual litter production,with litter yield increasing from 0.9 to 8.4 Mg ha^(−1)across different physiognomies,following the increment in vegetation structure.Monthly production was seasonal and similar among vegetation types,increasing during the dry season.Leaves comprised the dominant fraction(approx.85%)and litterfall seasonality primarily resulted from the concentration of leaf shedding during dry months.However,the temporal pattern of litterfall throughout the year showed a gradual reduction in the seasonality from open to closed vegetation types,likely following the decrease of deciduous species abundance in the plant community.Our results showed that changes in vegetation structure may affect spatial and temporal litterfall patterns in different physiognomies,which co-occur across the Cerrado landscape,with potential implications for the overall functioning of this ecosystem.Moreover,these findings highlight the use of standardized methods as essential to correctly compare litterfall patterns among different environments.
