Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as...Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as a case study and employing the Criteria Importance Through Intercriteria Correlation(CRITIC)method,a modified model of coupling degree was developed to evaluate the car-rying capacity of water and land resources systems endowment and utilization,as well as their coupling coordination degree from 2013 to 2020.Our findings indicate that the water and land resources of Yulin are diminishing due to declines in agriculture,higher industrial water use,and wetland shrinkage.However,reallocating domestic water for ecological sustainability and reducing sloping farmland can mitigate this trend of decline.Temporally,as the coupling coordination between water and land resources system endowment in Yulin continuously improved,the coupling coordination between water and land resources system utilization first decreased and then in-creased with 2016 as the turning point.Spatially,the carrying capacity of water and land resources systems,the coupling coordination degree between water and land resources system endowment,and the coupling coordination degree between water and land resources system utilization in Yulin exhibited the same pattern of being higher in the six northern counties than in the six southern counties.Improving the water resources endowment is vital for the highly efficient use of water and land resources.展开更多
Ecological restoration projects implemented over the past 20 years have substantially increased forest coverage in China,but the high tree mortality of new afforestation forest remains a challenging but unsolved probl...Ecological restoration projects implemented over the past 20 years have substantially increased forest coverage in China,but the high tree mortality of new afforestation forest remains a challenging but unsolved problem.It is still not clear how much vegetation can be sustained by the forest lands with given water,energy and soil conditions,i.e.,the carrying capacity for vegetation(CCV)of forest lands,which is the prerequisite for planning and implementing forest restoration projects.Here,we used a simplified method to evaluate the CCV across forest lands nationwide.Specifically,based on leaf area index(LAI)dataset,we use boosted regression tree and multiple linear regression model to analyze the CCV during 2001-2020 and 2021-2030 and explore the contribution of environmental factors.We find that there are three typical regions with lower CCV located in the Loess Plateau and the southern region of the Inner Mongolia Plateau,the Hengduan Mountain region,and the Tianshan Mountains.More importantly,the vegetation in the regions near the dry-wet climate transition zone show excess local carrying capacity for vegetation over the past two decades and they are more susceptible to potential climatic stress.In comparison,in the Greater Khingan Mountains and Hengduan Mountains,there is high potential to improve the forest growth.Temperature,precipitation and soil affects the CCV by shaping the vegetation in the optimal range.This indicates that more consideration should be given to restrictions of regional environmental constraints when planning afforestation and forest management.This study has important implications for guiding future forest scheme in China.展开更多
Tourism is a popular activity that allows individuals to escape their daily routines and explore new destinations for various reasons,including leisure,pleasure,or business.A recent study has proposed a unique mathema...Tourism is a popular activity that allows individuals to escape their daily routines and explore new destinations for various reasons,including leisure,pleasure,or business.A recent study has proposed a unique mathematical concept called a q−Rung orthopair fuzzy hypersoft set(q−ROFHS)to enhance the formal representation of human thought processes and evaluate tourism carrying capacity.This approach can capture the imprecision and ambiguity often present in human perception.With the advanced mathematical tools in this field,the study has also incorporated the Einstein aggregation operator and score function into the q−ROFHS values to supportmultiattribute decision-making algorithms.By implementing this technique,effective plans can be developed for social and economic development while avoiding detrimental effects such as overcrowding or environmental damage caused by tourism.A case study of selected tourism carrying capacity will demonstrate the proposed methodology.展开更多
Under the background of new infrastructure,the Yellow River Basin’s superior growth cannot be separated originating with the synergistic effect of scientific and technological inventiveness and ecological civilizatio...Under the background of new infrastructure,the Yellow River Basin’s superior growth cannot be separated originating with the synergistic effect of scientific and technological inventiveness and ecological civilization construction.In light of the coupling coordination analysis of the coordination effect of provincial high-tech industry agglomeration and resource carrying capacity in the Yellow River Basin from 2009 to 2021,The evolution of the geographical and temporal pattern of development was investigated using the Moran index and kernel density estimation.The results show that the agglomeration of high-tech industries in the Yellow River Basin presents a development trend of seek improvement in stability,and there is a good coupling and coordination throughout the progression of scientific and technological innovation and the loading capacity of the resource,from the viewpoint of a time series.From the perspective of spatial pattern distribution,the whole basin aims at the lower reaches,accelerates the optimization of digital industry and promotes Yellow River Basin development of superior quality through innovation support and increase of input,and based on policy guidance.展开更多
Research on carrying capacity, aiming at maintaining the limited ability of the Earth's life supporting system to sustain human development, requires a comprehensive and ecosystem-based approach to monitor and assess...Research on carrying capacity, aiming at maintaining the limited ability of the Earth's life supporting system to sustain human development, requires a comprehensive and ecosystem-based approach to monitor and assess the localized sustainability of coupled social and ecological systems. A definition termed the ecosystem-based carrying capacity of island(EBCCI) was developed in this paper of which the indices of fundamental and realized carrying capacities of island(FCCI and RCCI) were highlighted to emphasize the inter-dependencies between social systems and ecological systems. In order to avoid the difficulties and uncertainties of direct assessment, the related assessment model was established on the basis of synthetic evaluation of inherent and external factors affecting the EBCCI. The southern Miaodao Archipelago(SMA) located in the intersection of the Bohai Sea and the Yellow Sea, China, was taken as a typical example to acquire integrated recognition of the island ecosystem and its carrying capacity so as to discuss its sustainable development. The index scores of FCCI and RCCI in the SMA were 0.818 5 and 0.712 9 out of 1.0, respectively, with acceptable uncertainties. The results showed a relatively well capacity to sustain progress and relatively well realization of the carrying capacity of island ecosystem, owing to a well capacity of ecologically regulating, general performance of both ecologically supporting and resource provisioning, and a relatively high level of social supporting system. The study implied that it was critical to optimize the inter-dependencies and to sustain the relative balance between social systems and ecological systems so as to improve the RCCI and further facilitate the sustainability of SMA. The approach proposed in this paper provides a powerful tool which is well applicative to the regional level of an oceanic island or archipelago to study the sustainable development and can be further popularized to the coastal zone.展开更多
The water resource carrying capacity(WRCC)in river basin changes dynamically under climate change,economic development,and technological advancement.Climate change affects hydrological processes and spatial/temporal d...The water resource carrying capacity(WRCC)in river basin changes dynamically under climate change,economic development,and technological advancement.Climate change affects hydrological processes and spatial/temporal distribution of water resources;while economic develo-ment and technological advancement can also affect the balance of water resources systems.Under climate change,economic development,and technological advancement,itis of great significance to explore the dynamic behavior of WRCC in river basins.This will help to alleviate water resources security issues and build a sustainable water resources system.This study was carried out to evaluate the dynamic WRCC using the"climate,economics,and technology-control objective inversion mode",which used total water consumption,water-use efficiency,and restrained total pollutant control in the water functional area as boundary conditions.This study was conducted on the Keriya River Basin,a sub-catchment located in southem margin of the Taklimakan Desert.The WRCC in the Keriya River Basin in 2015 was calculated,and the trends in the short term(2020),middle tem(2030),and long term(2050)were predicted.The results revealed that climate change factors have a positive effect on WRCC in the Keriya River Basin,which leads to an increase in total water resources.Economic and technological development exhibits an overall positive effect,while increasing in water consumption and sewage discharge exhibit a negative effect.展开更多
Assessing rangeland productivity is critical to reduce ecological degradation and promote sustainable livestock management.Here,we estimated biomass productivity and carrying capacity dynamics in the Borana rangeland ...Assessing rangeland productivity is critical to reduce ecological degradation and promote sustainable livestock management.Here,we estimated biomass productivity and carrying capacity dynamics in the Borana rangeland of southern Ethiopia by using field-based data and remote sensing data(i.e.,normalized difference vegetation index(NDVI)).Data was collected from both rainy and dry seasons when biomass production was high and low respectively.Results of linear regression showed that both biomass production(R^(2)_(adj)=0.672)and NDVI value(R^(2)_(adj)=0.471)were significantly decreased from 1990 to 2019.Field data and NDVI values for mean annual biomass showed a significant linear relationship.The model accuracy in the annual relationship between the observed and predicted biomass values was strong(R^(2)_(adj)=0.986)but with high standard error,indicating that the observed biomass production in the rangeland area was not in good condition as compared with the predicted one.This study suggests that,using NDVI data and field-based data in combined way has high potential to estimate rangeland biomass and carrying capacity dynamics at extensively grazed arid and semi-arid rangelands.And to use for estimating stoking rates and predicting future management techniques for decision making.展开更多
The topic of "China’s foreign policy under new circumstances" for discussion raised by Experts Forum of Contemporary International Relations is very important, because situation determines tasks, tasks prod...The topic of "China’s foreign policy under new circumstances" for discussion raised by Experts Forum of Contemporary International Relations is very important, because situation determines tasks, tasks produce policies and foreign policy is the continuation of domestic policy.展开更多
As Mianyang has neglected the coordination relationship with the ecological environment in the course of rapid urbanization,its ecological environment is getting worse.To this end,this study used the ecological footpr...As Mianyang has neglected the coordination relationship with the ecological environment in the course of rapid urbanization,its ecological environment is getting worse.To this end,this study used the ecological footprint method to explore the ecological carrying capacity of Mianyang from 2007 to 2014 under the background of rapid urbanization,which has important guiding significance for the future development of Mianyang.The results showed that in 2007–2014,the ecological footprint of Mianyang was greater than its ecological carrying capacity,indicating that Mianyang is in an ecological deficit.Specifically,the per capita ecological footprint showed a downtrend,and the per capita ecological carrying capacity showed a trend of smooth decline.In addition,the per capita ecological deficit was generally decreasing.In summary,Mianyang was generally in an ecological deficit in 2007–2014.Thus,the ecological environment of the region should be protected,in order to promote the sustainable development of the ecosystem in the region.展开更多
Based on the actual situation of Pai-Medog hiking route, the tourism environmental carrying capacity of this route was calculated in this study. According to the analysis and calculation results and referring to the c...Based on the actual situation of Pai-Medog hiking route, the tourism environmental carrying capacity of this route was calculated in this study. According to the analysis and calculation results and referring to the common control measures of tourism environmental carrying capacity, corresponding control measures were put forward for the Pai-Medog hiking route.展开更多
Voices are growing louder and louder,calling for vigorously carryingout the foreign trade agency system in China’s foreign economic andtrade field.Vice Premier Li Lanqing in charge of foreign trade andeconomic cooper...Voices are growing louder and louder,calling for vigorously carryingout the foreign trade agency system in China’s foreign economic andtrade field.Vice Premier Li Lanqing in charge of foreign trade andeconomic cooperation has pointed out many times recently that theoperational mode of foreign trade should be transferred from thetraditional purchase system to service-type agency system.This isimportant to deepening the reform of the foreign trade system.展开更多
The export enterprises of China have made outstanding achievements in carrying out the ISO 9000, according to the State Commodity Inspection Bureau. By the end of May 1995, 130 export enterprises had been issued with ...The export enterprises of China have made outstanding achievements in carrying out the ISO 9000, according to the State Commodity Inspection Bureau. By the end of May 1995, 130 export enterprises had been issued with the certificate of appraised quality after passing the assessment of the CCQSEM of ISO 9000. These enterprises have shown great superiority in signing contracts with foreign undertakings in bidding, export expansion, the rise of sales prices and the reduction of the rate of sub-standard goods.展开更多
Institute of Oceanology of the CAS (IOCAS) isamong the first batch of the Pilot institutes forimplementing reforms as a research base designatedby the CAS in 1997. In the light of the guidingprinciple of the CAS in st...Institute of Oceanology of the CAS (IOCAS) isamong the first batch of the Pilot institutes forimplementing reforms as a research base designatedby the CAS in 1997. In the light of the guidingprinciple of the CAS in structure readjustment andits planning for pilot project of knowledge innova-tion program, the IOCAS has reexamined its orien-tation, disciplinary layout, research structure andoperating mechanism, further clarified its innova-展开更多
Water risk early warning systems based on the water environmental carrying capacity(WECC)are powerful and effective tools to guarantee the sustainability of rivers.Existing work on the early warning of WECC has mainly...Water risk early warning systems based on the water environmental carrying capacity(WECC)are powerful and effective tools to guarantee the sustainability of rivers.Existing work on the early warning of WECC has mainly concerned the comprehensive evaluation of the status quo and lacked a quantitative prejudgement and warning of future overload.In addition,existing quantitative methods for short-term early warning have rarely focused on the integrated change trends of the early warning indicators.Given the periodicity of the socioeconomic system,however,the water environmental system also follows a trend of cyclical fluctuations.Thus,it is meaningful to monitor and use this periodicity for the early warning of the WECC.In this study,we first adopted and improved the prosperity index method to develop an integrated water risk early warning framework.We also constructed a forecast model to qualitatively and quantitatively prejudge and warn about the development trends of the water environmental system.We selected the North Canal Basin(an essential connection among the Beijing-Tianjin-Hebei region)in China as a case study and predicted the WECC in 25 water environmental management units of the basin in 2018–2023.We found that the analysis of the prosperity index was helpful in predicting the WECC,to some extent.The result demonstrated that the early warning system provided reliable prediction(root mean square error of 0.0651 and mean absolute error of 0.1418),and the calculation results of the comprehensive early warning index(CEWI)conformed to the actual situation and related research in the river basin.From 2008 to 2023,the WECC of most water environmental management units in the basin had improved but with some spatial differences:the CEWI was generally poor in areas with many human disturbances,while it was relatively good in the upstream regions with higher forest and grass covers as well as in the downstream areas with larger water volume.Finally,through a sensitivity analysis of the indicators,we proposed specific management measures for the sustainability of the water environmental system in the North Canal Basin.Overall,the integrated water risk early warning framework could provide an appropriate method for the water environmental administration department to predict the WECC of the basin in the future.This framework could also assist in implementing corresponding management measures in advance,especially for the performance evaluation and the arrangement of key short-term tasks in the River Chief System in China.展开更多
From the concept of carrying capacity proposed in the early 20th century to as an important tool for describing development constraints in the 21st century,many scholars have conducted extensive and detailed research ...From the concept of carrying capacity proposed in the early 20th century to as an important tool for describing development constraints in the 21st century,many scholars have conducted extensive and detailed research on carrying capacity at different levels,but the carrying capacity system has not yet formed a unified theoretical and methodological system.By summarizing and analyzing the existing literature,based on the viewpoints of Mr.Gao Jixi and Mr.Zeng Weihua,the relationship between different mainstream carrying capacities is analyzed,and finally a system for summarizing the elements of different carrying capacities is provided,which to some extent serves as a reference for scholars who have just come into contact with the concept of carrying capacity.It is thought that:①the research on ecological carrying capacity covers the scope of cities,and the research at the urban level complements the neglected and insufficient areas of ecological research.②The main difference among ecological carrying capacity,urban comprehensive carrying capacity and resource environment carrying capacity lies in the different research scopes.In the mainstream view,environmental carrying capacity and resource carrying capacity are summarized under the framework of different research scopes.Water environment carrying capacity,land resource carrying capacity and other single factor carrying capacity are special in-depth studies of environment and resource carrying capacity.③Ecological carrying capacity at the ecological level includes environmental carrying capacity and resource carrying capacity.At the urban level,urban ecology is equivalent to urban environment to a certain extent,and resources can be classified into urban environmental carrying capacity as an environmental element.展开更多
River Tapi is the prime water body for Surat city, Gujarat, India. On a long stretch of 22.39 km in Surat city (Kamrej to Causeway) of the Tapi river, there are many identified and non-identified discharge points avai...River Tapi is the prime water body for Surat city, Gujarat, India. On a long stretch of 22.39 km in Surat city (Kamrej to Causeway) of the Tapi river, there are many identified and non-identified discharge points available. Excessive discharge from these points restricts the efficiency of the self-purification process which ultimately degrades the river water quality. In this paper, an attempt has been made to estimate the pollutant load-carrying capacity at different segments of the river Tapi using the QUAL2Kw tool. The study has been undertaken with different scenarios: First, the QUAL2Kw model was trained with available river water quality and hydraulic data of the Tapi river in which the complete river segment was divided into 21 reaches. The model was calibrated and validated with the actual concentrations of the pollutants entering. In the second phase, all the point source, non-point source, and headwater characteristics were considered and the pollutant load-carrying capacity of the river in terms of BOD, ISS, and N-nitrate was found. In the third phase, all the sources of pollutants entering the river have been removed and only headwater characteristics were considered for the study. The results indicate that reach no. 21 (21.23ºN, 72.82ºE) has the maximum load-carrying capacity of Biochemical Oxygen Demand (BOD) up to 2057.7 kg/day, Inorganic Suspended Solids (ISS) up to 85633.8 kg/day, and Nitrate (NO<sub>3</sub>) up to 31688.8 kg/day. However, reach no. 4 has the minimum load carrying capacity of BOD up to 1088.1 kg/day, reach 8 carries a minimum of ISS 205341.6 kg/day and NO3 10215.57 kg/day.展开更多
基金Under the auspices of the National Natural Science Foundation of China(No.42271279,41931293,41801175)。
文摘Quantitatively assessing the carrying capacity of water and land resources systems in arid and semi-arid areas is crucial for achieving the 2030 Sustainable Development Goals.In this work,taking Yulin City in China as a case study and employing the Criteria Importance Through Intercriteria Correlation(CRITIC)method,a modified model of coupling degree was developed to evaluate the car-rying capacity of water and land resources systems endowment and utilization,as well as their coupling coordination degree from 2013 to 2020.Our findings indicate that the water and land resources of Yulin are diminishing due to declines in agriculture,higher industrial water use,and wetland shrinkage.However,reallocating domestic water for ecological sustainability and reducing sloping farmland can mitigate this trend of decline.Temporally,as the coupling coordination between water and land resources system endowment in Yulin continuously improved,the coupling coordination between water and land resources system utilization first decreased and then in-creased with 2016 as the turning point.Spatially,the carrying capacity of water and land resources systems,the coupling coordination degree between water and land resources system endowment,and the coupling coordination degree between water and land resources system utilization in Yulin exhibited the same pattern of being higher in the six northern counties than in the six southern counties.Improving the water resources endowment is vital for the highly efficient use of water and land resources.
基金supported by the Joint CAS-MPG Research Project(Grant No.HZXM20225001MI)the National Natural Science Founda-tion of China(NSFC)(Grant No.41991234)the National Science Foundation(Grant No.1903722).
文摘Ecological restoration projects implemented over the past 20 years have substantially increased forest coverage in China,but the high tree mortality of new afforestation forest remains a challenging but unsolved problem.It is still not clear how much vegetation can be sustained by the forest lands with given water,energy and soil conditions,i.e.,the carrying capacity for vegetation(CCV)of forest lands,which is the prerequisite for planning and implementing forest restoration projects.Here,we used a simplified method to evaluate the CCV across forest lands nationwide.Specifically,based on leaf area index(LAI)dataset,we use boosted regression tree and multiple linear regression model to analyze the CCV during 2001-2020 and 2021-2030 and explore the contribution of environmental factors.We find that there are three typical regions with lower CCV located in the Loess Plateau and the southern region of the Inner Mongolia Plateau,the Hengduan Mountain region,and the Tianshan Mountains.More importantly,the vegetation in the regions near the dry-wet climate transition zone show excess local carrying capacity for vegetation over the past two decades and they are more susceptible to potential climatic stress.In comparison,in the Greater Khingan Mountains and Hengduan Mountains,there is high potential to improve the forest growth.Temperature,precipitation and soil affects the CCV by shaping the vegetation in the optimal range.This indicates that more consideration should be given to restrictions of regional environmental constraints when planning afforestation and forest management.This study has important implications for guiding future forest scheme in China.
基金the National Research Foundation of Korea(NRF)grant funded by the Korea government(MSIT)(No.2021R1A4A1031509).
文摘Tourism is a popular activity that allows individuals to escape their daily routines and explore new destinations for various reasons,including leisure,pleasure,or business.A recent study has proposed a unique mathematical concept called a q−Rung orthopair fuzzy hypersoft set(q−ROFHS)to enhance the formal representation of human thought processes and evaluate tourism carrying capacity.This approach can capture the imprecision and ambiguity often present in human perception.With the advanced mathematical tools in this field,the study has also incorporated the Einstein aggregation operator and score function into the q−ROFHS values to supportmultiattribute decision-making algorithms.By implementing this technique,effective plans can be developed for social and economic development while avoiding detrimental effects such as overcrowding or environmental damage caused by tourism.A case study of selected tourism carrying capacity will demonstrate the proposed methodology.
基金supported by the 2021 Research and Practice Project of Higher Education Teaching Reform in Henan Province(Grant No.2021SJGLX072Y).
文摘Under the background of new infrastructure,the Yellow River Basin’s superior growth cannot be separated originating with the synergistic effect of scientific and technological inventiveness and ecological civilization construction.In light of the coupling coordination analysis of the coordination effect of provincial high-tech industry agglomeration and resource carrying capacity in the Yellow River Basin from 2009 to 2021,The evolution of the geographical and temporal pattern of development was investigated using the Moran index and kernel density estimation.The results show that the agglomeration of high-tech industries in the Yellow River Basin presents a development trend of seek improvement in stability,and there is a good coupling and coordination throughout the progression of scientific and technological innovation and the loading capacity of the resource,from the viewpoint of a time series.From the perspective of spatial pattern distribution,the whole basin aims at the lower reaches,accelerates the optimization of digital industry and promotes Yellow River Basin development of superior quality through innovation support and increase of input,and based on policy guidance.
基金The Special Project of Science and Technology Fundamental Work from the Ministry of Science and Technology of China under contract No.2012FY112500the National Natural Science Foundation of China under contract No.41206111
文摘Research on carrying capacity, aiming at maintaining the limited ability of the Earth's life supporting system to sustain human development, requires a comprehensive and ecosystem-based approach to monitor and assess the localized sustainability of coupled social and ecological systems. A definition termed the ecosystem-based carrying capacity of island(EBCCI) was developed in this paper of which the indices of fundamental and realized carrying capacities of island(FCCI and RCCI) were highlighted to emphasize the inter-dependencies between social systems and ecological systems. In order to avoid the difficulties and uncertainties of direct assessment, the related assessment model was established on the basis of synthetic evaluation of inherent and external factors affecting the EBCCI. The southern Miaodao Archipelago(SMA) located in the intersection of the Bohai Sea and the Yellow Sea, China, was taken as a typical example to acquire integrated recognition of the island ecosystem and its carrying capacity so as to discuss its sustainable development. The index scores of FCCI and RCCI in the SMA were 0.818 5 and 0.712 9 out of 1.0, respectively, with acceptable uncertainties. The results showed a relatively well capacity to sustain progress and relatively well realization of the carrying capacity of island ecosystem, owing to a well capacity of ecologically regulating, general performance of both ecologically supporting and resource provisioning, and a relatively high level of social supporting system. The study implied that it was critical to optimize the inter-dependencies and to sustain the relative balance between social systems and ecological systems so as to improve the RCCI and further facilitate the sustainability of SMA. The approach proposed in this paper provides a powerful tool which is well applicative to the regional level of an oceanic island or archipelago to study the sustainable development and can be further popularized to the coastal zone.
文摘The water resource carrying capacity(WRCC)in river basin changes dynamically under climate change,economic development,and technological advancement.Climate change affects hydrological processes and spatial/temporal distribution of water resources;while economic develo-ment and technological advancement can also affect the balance of water resources systems.Under climate change,economic development,and technological advancement,itis of great significance to explore the dynamic behavior of WRCC in river basins.This will help to alleviate water resources security issues and build a sustainable water resources system.This study was carried out to evaluate the dynamic WRCC using the"climate,economics,and technology-control objective inversion mode",which used total water consumption,water-use efficiency,and restrained total pollutant control in the water functional area as boundary conditions.This study was conducted on the Keriya River Basin,a sub-catchment located in southem margin of the Taklimakan Desert.The WRCC in the Keriya River Basin in 2015 was calculated,and the trends in the short term(2020),middle tem(2030),and long term(2050)were predicted.The results revealed that climate change factors have a positive effect on WRCC in the Keriya River Basin,which leads to an increase in total water resources.Economic and technological development exhibits an overall positive effect,while increasing in water consumption and sewage discharge exhibit a negative effect.
基金the University of Chinese Academy of Science (UCAS) and CAS-TWAS fellowship program that provide funding and the PhD Scholarship for the first authorthe African Great Green Wall Adaptation Technical Cooperation Research and Demonstration (2018YFE0106000)+5 种基金Science and Technology Partnership Program,Ministry of Science and Technology of China (Grant No.KY201702010)Integration and application of appropriate technologies for desertification control in Africa (Grant No.SAJC202108)International cooperation and Exchanges NSFC (Grant No.41861144020) financial support to do this paperthe CAS Key Technology Talent Program supportthe support of the "Tianchi doctor program" of Xinjiang Uygur Autonomous Region in 2020the ESA CCI Land Cover project
文摘Assessing rangeland productivity is critical to reduce ecological degradation and promote sustainable livestock management.Here,we estimated biomass productivity and carrying capacity dynamics in the Borana rangeland of southern Ethiopia by using field-based data and remote sensing data(i.e.,normalized difference vegetation index(NDVI)).Data was collected from both rainy and dry seasons when biomass production was high and low respectively.Results of linear regression showed that both biomass production(R^(2)_(adj)=0.672)and NDVI value(R^(2)_(adj)=0.471)were significantly decreased from 1990 to 2019.Field data and NDVI values for mean annual biomass showed a significant linear relationship.The model accuracy in the annual relationship between the observed and predicted biomass values was strong(R^(2)_(adj)=0.986)but with high standard error,indicating that the observed biomass production in the rangeland area was not in good condition as compared with the predicted one.This study suggests that,using NDVI data and field-based data in combined way has high potential to estimate rangeland biomass and carrying capacity dynamics at extensively grazed arid and semi-arid rangelands.And to use for estimating stoking rates and predicting future management techniques for decision making.
文摘The topic of "China’s foreign policy under new circumstances" for discussion raised by Experts Forum of Contemporary International Relations is very important, because situation determines tasks, tasks produce policies and foreign policy is the continuation of domestic policy.
文摘As Mianyang has neglected the coordination relationship with the ecological environment in the course of rapid urbanization,its ecological environment is getting worse.To this end,this study used the ecological footprint method to explore the ecological carrying capacity of Mianyang from 2007 to 2014 under the background of rapid urbanization,which has important guiding significance for the future development of Mianyang.The results showed that in 2007–2014,the ecological footprint of Mianyang was greater than its ecological carrying capacity,indicating that Mianyang is in an ecological deficit.Specifically,the per capita ecological footprint showed a downtrend,and the per capita ecological carrying capacity showed a trend of smooth decline.In addition,the per capita ecological deficit was generally decreasing.In summary,Mianyang was generally in an ecological deficit in 2007–2014.Thus,the ecological environment of the region should be protected,in order to promote the sustainable development of the ecosystem in the region.
基金Sponsored by Natural Science Foundation of Science and Technology Department of Tibet(2016ZR-NQ-10)
文摘Based on the actual situation of Pai-Medog hiking route, the tourism environmental carrying capacity of this route was calculated in this study. According to the analysis and calculation results and referring to the common control measures of tourism environmental carrying capacity, corresponding control measures were put forward for the Pai-Medog hiking route.
文摘Voices are growing louder and louder,calling for vigorously carryingout the foreign trade agency system in China’s foreign economic andtrade field.Vice Premier Li Lanqing in charge of foreign trade andeconomic cooperation has pointed out many times recently that theoperational mode of foreign trade should be transferred from thetraditional purchase system to service-type agency system.This isimportant to deepening the reform of the foreign trade system.
文摘The export enterprises of China have made outstanding achievements in carrying out the ISO 9000, according to the State Commodity Inspection Bureau. By the end of May 1995, 130 export enterprises had been issued with the certificate of appraised quality after passing the assessment of the CCQSEM of ISO 9000. These enterprises have shown great superiority in signing contracts with foreign undertakings in bidding, export expansion, the rise of sales prices and the reduction of the rate of sub-standard goods.
文摘Institute of Oceanology of the CAS (IOCAS) isamong the first batch of the Pilot institutes forimplementing reforms as a research base designatedby the CAS in 1997. In the light of the guidingprinciple of the CAS in structure readjustment andits planning for pilot project of knowledge innova-tion program, the IOCAS has reexamined its orien-tation, disciplinary layout, research structure andoperating mechanism, further clarified its innova-
基金supported by the National Key R&D Program of China(2021YFB3901104).
文摘Water risk early warning systems based on the water environmental carrying capacity(WECC)are powerful and effective tools to guarantee the sustainability of rivers.Existing work on the early warning of WECC has mainly concerned the comprehensive evaluation of the status quo and lacked a quantitative prejudgement and warning of future overload.In addition,existing quantitative methods for short-term early warning have rarely focused on the integrated change trends of the early warning indicators.Given the periodicity of the socioeconomic system,however,the water environmental system also follows a trend of cyclical fluctuations.Thus,it is meaningful to monitor and use this periodicity for the early warning of the WECC.In this study,we first adopted and improved the prosperity index method to develop an integrated water risk early warning framework.We also constructed a forecast model to qualitatively and quantitatively prejudge and warn about the development trends of the water environmental system.We selected the North Canal Basin(an essential connection among the Beijing-Tianjin-Hebei region)in China as a case study and predicted the WECC in 25 water environmental management units of the basin in 2018–2023.We found that the analysis of the prosperity index was helpful in predicting the WECC,to some extent.The result demonstrated that the early warning system provided reliable prediction(root mean square error of 0.0651 and mean absolute error of 0.1418),and the calculation results of the comprehensive early warning index(CEWI)conformed to the actual situation and related research in the river basin.From 2008 to 2023,the WECC of most water environmental management units in the basin had improved but with some spatial differences:the CEWI was generally poor in areas with many human disturbances,while it was relatively good in the upstream regions with higher forest and grass covers as well as in the downstream areas with larger water volume.Finally,through a sensitivity analysis of the indicators,we proposed specific management measures for the sustainability of the water environmental system in the North Canal Basin.Overall,the integrated water risk early warning framework could provide an appropriate method for the water environmental administration department to predict the WECC of the basin in the future.This framework could also assist in implementing corresponding management measures in advance,especially for the performance evaluation and the arrangement of key short-term tasks in the River Chief System in China.
文摘From the concept of carrying capacity proposed in the early 20th century to as an important tool for describing development constraints in the 21st century,many scholars have conducted extensive and detailed research on carrying capacity at different levels,but the carrying capacity system has not yet formed a unified theoretical and methodological system.By summarizing and analyzing the existing literature,based on the viewpoints of Mr.Gao Jixi and Mr.Zeng Weihua,the relationship between different mainstream carrying capacities is analyzed,and finally a system for summarizing the elements of different carrying capacities is provided,which to some extent serves as a reference for scholars who have just come into contact with the concept of carrying capacity.It is thought that:①the research on ecological carrying capacity covers the scope of cities,and the research at the urban level complements the neglected and insufficient areas of ecological research.②The main difference among ecological carrying capacity,urban comprehensive carrying capacity and resource environment carrying capacity lies in the different research scopes.In the mainstream view,environmental carrying capacity and resource carrying capacity are summarized under the framework of different research scopes.Water environment carrying capacity,land resource carrying capacity and other single factor carrying capacity are special in-depth studies of environment and resource carrying capacity.③Ecological carrying capacity at the ecological level includes environmental carrying capacity and resource carrying capacity.At the urban level,urban ecology is equivalent to urban environment to a certain extent,and resources can be classified into urban environmental carrying capacity as an environmental element.
文摘River Tapi is the prime water body for Surat city, Gujarat, India. On a long stretch of 22.39 km in Surat city (Kamrej to Causeway) of the Tapi river, there are many identified and non-identified discharge points available. Excessive discharge from these points restricts the efficiency of the self-purification process which ultimately degrades the river water quality. In this paper, an attempt has been made to estimate the pollutant load-carrying capacity at different segments of the river Tapi using the QUAL2Kw tool. The study has been undertaken with different scenarios: First, the QUAL2Kw model was trained with available river water quality and hydraulic data of the Tapi river in which the complete river segment was divided into 21 reaches. The model was calibrated and validated with the actual concentrations of the pollutants entering. In the second phase, all the point source, non-point source, and headwater characteristics were considered and the pollutant load-carrying capacity of the river in terms of BOD, ISS, and N-nitrate was found. In the third phase, all the sources of pollutants entering the river have been removed and only headwater characteristics were considered for the study. The results indicate that reach no. 21 (21.23ºN, 72.82ºE) has the maximum load-carrying capacity of Biochemical Oxygen Demand (BOD) up to 2057.7 kg/day, Inorganic Suspended Solids (ISS) up to 85633.8 kg/day, and Nitrate (NO<sub>3</sub>) up to 31688.8 kg/day. However, reach no. 4 has the minimum load carrying capacity of BOD up to 1088.1 kg/day, reach 8 carries a minimum of ISS 205341.6 kg/day and NO3 10215.57 kg/day.