The calculation of ecological compensation and boundary identification of stakeholders represent the key challenges for Beijing-Tianjin-Hebei Region in its implementation of the trans-regional ecological compensation ...The calculation of ecological compensation and boundary identification of stakeholders represent the key challenges for Beijing-Tianjin-Hebei Region in its implementation of the trans-regional ecological compensation mechanism.Breaking administrative boundaries and spatially coordinating ecological resources helps to restructure an ecological compensation mechanism of the region based on the coordinated development of Beijing,Tianjin and Hebei.According to the estimated ecological assets in the counties of the region in 2000,2005,2010 and 2015,a quantitative model for total ecological compensation was built based on ecological assets and county-level economic development.Then,the spatiotemporal distribution characteristics of the total ecological compensation in the region were defined,and the boundaries of ecological surplus and deficit areas were identified.Results indicate:(1)The region’s annual average ecological assets amounted to￥1379.47 billion;in terms of annual total ecological assets,Hebei ranked first(￥1123.80 billion),followed by Beijing(￥157.46 billion)and Tianjin(￥98.21 billion);and in terms of ecological assets per unit area,Beijing ranked first,Tianjin second and Hebei last.(2)Among ecosystem services,hydrological regulation and climate regulation had the highest annual average value and contributed most to the increase in ecological assets.In 2015,the contribution of water and soil conservation to the total ecological assets decreased to-15.66%,showing the degradation of the function played by different ecosystems.(3)The ecological surplus of the region in four periods of 2000,2005,2010 and 2015 were￥398.98 billion,￥870.37 billion,￥1254.93 billion and￥2693.94 billion respectively,basically offsetting the ecological deficit of each corresponding period,but the urgency for ecological compensation was increased.(4)The ecological surplus and deficit areas showed a great fluctuation in different time periods.Larger time span means more noticeable convergence of deficit areas towards central and eastern areas.Public resources such as education,transportation and medical care in central urban areas should be decentralized to encourage population dispersal,weaken the agglomeration effect of deficit areas and finally achieve the ecological synergy of the region.展开更多
Construction of the ecological compensation mechanism is an important approach to put the“Beijing-Tianjin-Hebei Coordinated Development Plan”into practice and improve the ecological environment of the Beijing-Tianji...Construction of the ecological compensation mechanism is an important approach to put the“Beijing-Tianjin-Hebei Coordinated Development Plan”into practice and improve the ecological environment of the Beijing-Tianjin-Hebei region.This paper constructs an ecological compensation mechanism for the Beijing-Tianjin-Hebei region based on the footprint balance and footprint deficit after clarifying ecological governance objectives.First,this paper proposes to establish a uniform,hierarchical and classified supply mechanism of ecosystem services according to the classification of land resources,water resources and forest resources for the Beijing-Tianjin-Hebei region.Then,the“Authority with Corresponding Responsibility”for the supply of ecosystem services in the Beijing-Tianjin-Hebei region can be realized through a footprint balance and footprint deficit indicator circulation mechanism.Finally,the scientific and rational ecological compensation standard can be guaranteed through establishing the integrated governance mechanism for ecological compensation in the Beijing-Tianjin-Hebei region and improving the“ecological compensation standard”.The results of this paper can provide sound theoretical support for effectively promoting the improvement of ecosystem services and human well-being in the Beijing-Tianjin-Hebei region.展开更多
Ecological footprint is a new method to assess sustainable development quantitatively. It translates production into biologically productive areas offering material flows to measure the utilized degree of nature by hu...Ecological footprint is a new method to assess sustainable development quantitatively. It translates production into biologically productive areas offering material flows to measure the utilized degree of nature by humankind. At present, China runs ecological deficits because footprints required for consumption are larger than available ones. In the paper, the ecological footprint model is applied to calculate the deficits by resource, environment and import-export accounting. It is clear that the deficits have caused enormous pressure to resource and environment, which would become bigger with more factors of resource and environment being accounted. In the primary production and energy trade, import footprint turned from deficit to surplus after 1996, which benefited the conservation of national resource. But compared with the huge depletion caused by resource and environment, they had small effects on deficits.展开更多
The Jiangxi province was divided into seven parts according to the concept of watershed,namely Poyang lake area,Fuhe,Xinjiang,Ganjiang,Xiuhe,Raohe and other river watersheds.The ecological supply and demands status of...The Jiangxi province was divided into seven parts according to the concept of watershed,namely Poyang lake area,Fuhe,Xinjiang,Ganjiang,Xiuhe,Raohe and other river watersheds.The ecological supply and demands status of the former six parts from 2000 to 2006 was computed based on the ecological footprint model and a spatiotemporal comparative analysis to them was conducted.The result showed that:①all the studied areas had an increasing ecological deficit and they were in the status of unsustainable development;② the arable land footprint's demand were about 80% of their total footprint's demand respectively,so it was of great significance to protect and exploit arable land resources scientifically;③ the ecological deficit of grassland and forest resources can not be ignored.展开更多
The environmental impact caused by local people （ecological footprint of consumption, EFc） and the actual environmental impact that the ecosystem burdens （ecological footprint of production, EFp） in West Jilin Pro...The environmental impact caused by local people （ecological footprint of consumption, EFc） and the actual environmental impact that the ecosystem burdens （ecological footprint of production, EFp） in West Jilin Province, Northeast China from 1986 to 2006 were evaluated by using ecological footprint （EF） method. And the major driving forces of EFc and EFp were analyzed by STIRPAT model. Both EFc and EFp showed increasing trends in 1986-2006, accompanied by decreasing ecological deficits but expanding ecological overshoots. Population （P）, GDP per capita （A1）, quadratic term of GDP per capita （A2）, urbanization （Tα1）, and quadratic term of urbanization （Ta2） were important influencing factors of EFc, among which Tα2 and Tα1 were the most dominate driving forces of EFc. A1, A2 and Tα2 were important influencing factors of EFp, among which A2 and A1 were the most dominate driving forces of EFp. In 1986-2006, the classical Environmental Kuznets Curve hypothesis did not exist between A2 and EF （both EFc and EFp）, but did between Tα2 and EF. The results indicate that enhancing the urbanization process and diversifying economic sources is one of the most effective ways to reduce the environmental impact of West Jilin Province. Moreover, importance should be attached to improve the eco-efficiency of resource exploitation and consumption.展开更多
This paper researches the ecological sustainability of Zhangjiakou City, Hebei Province, China, using the ecological footprint model. According to the study we find that Zhangjiakou City was in the situation of ecolog...This paper researches the ecological sustainability of Zhangjiakou City, Hebei Province, China, using the ecological footprint model. According to the study we find that Zhangjiakou City was in the situation of ecological deficit from 1990 to 2000 and the deficit had the enlarging tendency. In 1990 the per capita ecological footprint was 0.964 and the per capita ecological capacity was 0.5 l 8, thus it can be calculated that the per capita ecological deficit was 4）.446. However in 2000, the per capita ecological footprint increased to 1.068, at the same time the per capita eco- logical capacity decreased to 0.471, then the per capita ecological deficit in 2000 was 4）.597. Furthermore, this paper studies the ecological sustainability of the city from the changes of the ecological footprint of per 10,000 yuan GDP and the productivity of ecological system. Finally the authors point out the shortage of the model and the way to improve it.展开更多
A fundamental element of sustainable development is that humans live within nature's biological capacity. Quantifying this, however, remains a significant challenge for which there are many emerging tools. The con...A fundamental element of sustainable development is that humans live within nature's biological capacity. Quantifying this, however, remains a significant challenge for which there are many emerging tools. The concept of the Ecological Footprint is one such accounting tool for comprehensive assessment of the status of sustainable development, based on integration of resource consumption and land capacity, reflecting the human impact on the environment. A region's development is defined as unsustainable when the Ecological Footprint surpasses the biological capacity. In this paper, the Ecological Footprint concept was applied in assessing the development of Yunnan Province, China in a period between 1988 and 2006. The results showed that the Ecological Footprint per capita in Yunnan rose from 0.854 gha in 1988 to 2.11 gha in 2006. Ecological deficit, defined as when the human demand on the land surpasses the regions biological productive capacity, emerged in 1991 and quickly increased from 0.02 gha in 1991 to 1.05 gha in 2006. The increase in the ecological deficit is primarily a result of the rapid increase in population and consumption level. To achieve sustainable development in Yunnan, production and consumption rates need to be modified.展开更多
Ecological footprint is a method of measuring how much we use the natural resources and how much the nature provides services for human beings. This paper summarized the application of ecological footprint at differen...Ecological footprint is a method of measuring how much we use the natural resources and how much the nature provides services for human beings. This paper summarized the application of ecological footprint at different scales and in different fields and different ecological types at home and abroad,analyzed the advantages and disadvantages of ecological footprint method,and made a prediction of the application of ecological footprint.展开更多
The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data i...The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data in 1950-1980, mean field water surplus or deficit on climatic, crop and cropland basis in dryland of northern China was calculated, and the pattern of field water surplus or deficit was analyzed and discussed in this paper.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
This paper,based on the ecological footprint component method,calculated the touristic ecological footprint of Jiufeng National Forest Park in Beijing.The results showed that in 2013,in Jiufeng National Forest Park,th...This paper,based on the ecological footprint component method,calculated the touristic ecological footprint of Jiufeng National Forest Park in Beijing.The results showed that in 2013,in Jiufeng National Forest Park,the total touristic ecological footprint was 183.08 hm2,the total ecological capacity was 225.16 hm2,the total touristic ecological surplus was 42.07 hm2,and the average touristic ecological surplus was 0.000 4 hm2 per capita,indicating that tourism in Jiufeng National Forest Park was in ecological surplus and ecological security.However,forest parks in Beijing at large were in ecological deficit.This paper suggested that the tourist flow volume of forest parks with a big ecological deficit should be moved to forest parks with an ecological surplus.Besides,forest parks are expected to strengthen the development and management,improve the availability of forest recreation resource,and promote the environmental protection awareness of tourists,so as to boost the sustainable development of forest park tourism.展开更多
Virtual water trade(VWT)provides a new perspective for alleviating water crisis and has thus attracted widespread attention.However,the heterogeneity of virtual water trade inside and outside the river basin and its i...Virtual water trade(VWT)provides a new perspective for alleviating water crisis and has thus attracted widespread attention.However,the heterogeneity of virtual water trade inside and outside the river basin and its influencing factors remains further study.In this study,for better investigating the pattern and heterogeneity of virtual water trade inside and outside provincial regions along the Yellow River Basin in 2015 using the input-output model(MRIO),we proposed two new concepts,i.e.,virtual water surplus and virtual water deficit,and then used the Logarithmic Mean Divisia Index(LMDI)model to identify the inherent mechanism of the imbalance of virtual water trade between provincial regions along the Yellow River Basin and the other four regions in China.The results show that:1)in provincial regions along the Yellow River Basin,the less developed the economy was,the larger the contribution of the agricultural sector in virtual water trade,while the smaller the contribution of the industrial sector.2)Due to the large output of agricultural products,the upstream and midstream provincial regions of the Yellow River Basin had a virtual water surplus,with a net outflow of virtual water of 2.7×10^(8) m^(3) and 0.9×10^(8) m^(3),respectively.3)provincial regions along the Yellow River Basin were in a virtual water deficit with the rest of China,and the decisive factor was the active degree of trade with the outside.This study would be beneficial to illuminate the trade-related water use issues in provincial regions along the Yellow River Basin,which has farreaching practical signific-ance for alleviating water scarcity.展开更多
We consider a continuous time risk model based on a two state Markov process, in which after an exponentially distributed time, the claim frequency changes to a different level and can change back again in the same wa...We consider a continuous time risk model based on a two state Markov process, in which after an exponentially distributed time, the claim frequency changes to a different level and can change back again in the same way. We derive the Laplace transform for the first passage time to surplus zero from a given negative surplus and for the duration of negative surplus. Closed-form expressions are given in the case of exponential individual claim. Finally, numerical results are provided to show how to estimate the moments of duration of negative surplus.展开更多
In this paper, we study the risk model with Markovian arrivals where we allow the surplus process to continue if the surplus falls below zero. We first derive expressions for the severity of ruin. Then by using the st...In this paper, we study the risk model with Markovian arrivals where we allow the surplus process to continue if the surplus falls below zero. We first derive expressions for the severity of ruin. Then by using the strong Markovian property of a two-dimensional Markov process and the expression for the severity of ruin, we obtain the Laplace transform of the total duration of negative surplus.展开更多
This paper explains the root cause of China＇s trade surplus and argues that it is rooted in structural factors. China＇s dual economic structure and the relatively slow growth in wages due to the abundant supply of l...This paper explains the root cause of China＇s trade surplus and argues that it is rooted in structural factors. China＇s dual economic structure and the relatively slow growth in wages due to the abundant supply of labor have led to a large supply glut between China＇s domestic demand and output, which has been balanced by export. This is a structural problem that cannot be solved by currency appreciation or the readjustment of capital account deficits. A potentially viable option is to adjust the current account by developing a new opening-up system featuring more freedom and compliance.展开更多
基金National Social Science Foundation of China,No.18BGL173,No.16CJY044Beijing Social Science Fund Project,China,No.16LJC009
文摘The calculation of ecological compensation and boundary identification of stakeholders represent the key challenges for Beijing-Tianjin-Hebei Region in its implementation of the trans-regional ecological compensation mechanism.Breaking administrative boundaries and spatially coordinating ecological resources helps to restructure an ecological compensation mechanism of the region based on the coordinated development of Beijing,Tianjin and Hebei.According to the estimated ecological assets in the counties of the region in 2000,2005,2010 and 2015,a quantitative model for total ecological compensation was built based on ecological assets and county-level economic development.Then,the spatiotemporal distribution characteristics of the total ecological compensation in the region were defined,and the boundaries of ecological surplus and deficit areas were identified.Results indicate:(1)The region’s annual average ecological assets amounted to￥1379.47 billion;in terms of annual total ecological assets,Hebei ranked first(￥1123.80 billion),followed by Beijing(￥157.46 billion)and Tianjin(￥98.21 billion);and in terms of ecological assets per unit area,Beijing ranked first,Tianjin second and Hebei last.(2)Among ecosystem services,hydrological regulation and climate regulation had the highest annual average value and contributed most to the increase in ecological assets.In 2015,the contribution of water and soil conservation to the total ecological assets decreased to-15.66%,showing the degradation of the function played by different ecosystems.(3)The ecological surplus of the region in four periods of 2000,2005,2010 and 2015 were￥398.98 billion,￥870.37 billion,￥1254.93 billion and￥2693.94 billion respectively,basically offsetting the ecological deficit of each corresponding period,but the urgency for ecological compensation was increased.(4)The ecological surplus and deficit areas showed a great fluctuation in different time periods.Larger time span means more noticeable convergence of deficit areas towards central and eastern areas.Public resources such as education,transportation and medical care in central urban areas should be decentralized to encourage population dispersal,weaken the agglomeration effect of deficit areas and finally achieve the ecological synergy of the region.
基金This research is supporteded by the Major Project of Humanities and Social Science Research of the Hebei Education Department(Grant No.ZD201907)the Young Scientists Fund of the Hebei College Science and Technology Research Program(Grant No.QN2018252)the Young Scientists Fund of the National Natural Science Foundation of China(Grant Nos..51909052,41807169).
文摘Construction of the ecological compensation mechanism is an important approach to put the“Beijing-Tianjin-Hebei Coordinated Development Plan”into practice and improve the ecological environment of the Beijing-Tianjin-Hebei region.This paper constructs an ecological compensation mechanism for the Beijing-Tianjin-Hebei region based on the footprint balance and footprint deficit after clarifying ecological governance objectives.First,this paper proposes to establish a uniform,hierarchical and classified supply mechanism of ecosystem services according to the classification of land resources,water resources and forest resources for the Beijing-Tianjin-Hebei region.Then,the“Authority with Corresponding Responsibility”for the supply of ecosystem services in the Beijing-Tianjin-Hebei region can be realized through a footprint balance and footprint deficit indicator circulation mechanism.Finally,the scientific and rational ecological compensation standard can be guaranteed through establishing the integrated governance mechanism for ecological compensation in the Beijing-Tianjin-Hebei region and improving the“ecological compensation standard”.The results of this paper can provide sound theoretical support for effectively promoting the improvement of ecosystem services and human well-being in the Beijing-Tianjin-Hebei region.
文摘Ecological footprint is a new method to assess sustainable development quantitatively. It translates production into biologically productive areas offering material flows to measure the utilized degree of nature by humankind. At present, China runs ecological deficits because footprints required for consumption are larger than available ones. In the paper, the ecological footprint model is applied to calculate the deficits by resource, environment and import-export accounting. It is clear that the deficits have caused enormous pressure to resource and environment, which would become bigger with more factors of resource and environment being accounted. In the primary production and energy trade, import footprint turned from deficit to surplus after 1996, which benefited the conservation of national resource. But compared with the huge depletion caused by resource and environment, they had small effects on deficits.
文摘The Jiangxi province was divided into seven parts according to the concept of watershed,namely Poyang lake area,Fuhe,Xinjiang,Ganjiang,Xiuhe,Raohe and other river watersheds.The ecological supply and demands status of the former six parts from 2000 to 2006 was computed based on the ecological footprint model and a spatiotemporal comparative analysis to them was conducted.The result showed that:①all the studied areas had an increasing ecological deficit and they were in the status of unsustainable development;② the arable land footprint's demand were about 80% of their total footprint's demand respectively,so it was of great significance to protect and exploit arable land resources scientifically;③ the ecological deficit of grassland and forest resources can not be ignored.
基金Under the auspices of Major State Basic Research Development Program of China(No.2004CB418507)
文摘The environmental impact caused by local people （ecological footprint of consumption, EFc） and the actual environmental impact that the ecosystem burdens （ecological footprint of production, EFp） in West Jilin Province, Northeast China from 1986 to 2006 were evaluated by using ecological footprint （EF） method. And the major driving forces of EFc and EFp were analyzed by STIRPAT model. Both EFc and EFp showed increasing trends in 1986-2006, accompanied by decreasing ecological deficits but expanding ecological overshoots. Population （P）, GDP per capita （A1）, quadratic term of GDP per capita （A2）, urbanization （Tα1）, and quadratic term of urbanization （Ta2） were important influencing factors of EFc, among which Tα2 and Tα1 were the most dominate driving forces of EFc. A1, A2 and Tα2 were important influencing factors of EFp, among which A2 and A1 were the most dominate driving forces of EFp. In 1986-2006, the classical Environmental Kuznets Curve hypothesis did not exist between A2 and EF （both EFc and EFp）, but did between Tα2 and EF. The results indicate that enhancing the urbanization process and diversifying economic sources is one of the most effective ways to reduce the environmental impact of West Jilin Province. Moreover, importance should be attached to improve the eco-efficiency of resource exploitation and consumption.
基金Under the auspices of the National Natural Science Foundation of China (No. 40171001)
文摘This paper researches the ecological sustainability of Zhangjiakou City, Hebei Province, China, using the ecological footprint model. According to the study we find that Zhangjiakou City was in the situation of ecological deficit from 1990 to 2000 and the deficit had the enlarging tendency. In 1990 the per capita ecological footprint was 0.964 and the per capita ecological capacity was 0.5 l 8, thus it can be calculated that the per capita ecological deficit was 4）.446. However in 2000, the per capita ecological footprint increased to 1.068, at the same time the per capita eco- logical capacity decreased to 0.471, then the per capita ecological deficit in 2000 was 4）.597. Furthermore, this paper studies the ecological sustainability of the city from the changes of the ecological footprint of per 10,000 yuan GDP and the productivity of ecological system. Finally the authors point out the shortage of the model and the way to improve it.
基金funded by the National Key Project for Basic Research of China (973), (Grant No.2003CB415100)
文摘A fundamental element of sustainable development is that humans live within nature's biological capacity. Quantifying this, however, remains a significant challenge for which there are many emerging tools. The concept of the Ecological Footprint is one such accounting tool for comprehensive assessment of the status of sustainable development, based on integration of resource consumption and land capacity, reflecting the human impact on the environment. A region's development is defined as unsustainable when the Ecological Footprint surpasses the biological capacity. In this paper, the Ecological Footprint concept was applied in assessing the development of Yunnan Province, China in a period between 1988 and 2006. The results showed that the Ecological Footprint per capita in Yunnan rose from 0.854 gha in 1988 to 2.11 gha in 2006. Ecological deficit, defined as when the human demand on the land surpasses the regions biological productive capacity, emerged in 1991 and quickly increased from 0.02 gha in 1991 to 1.05 gha in 2006. The increase in the ecological deficit is primarily a result of the rapid increase in population and consumption level. To achieve sustainable development in Yunnan, production and consumption rates need to be modified.
基金Supported by the Innovation Project for College Young Teachers in Tibet Autonomous Region"Ecological Economic System Assessment of Tibet Based on Ecological Footprint Theory"(QC2015-28)
文摘Ecological footprint is a method of measuring how much we use the natural resources and how much the nature provides services for human beings. This paper summarized the application of ecological footprint at different scales and in different fields and different ecological types at home and abroad,analyzed the advantages and disadvantages of ecological footprint method,and made a prediction of the application of ecological footprint.
基金The national key research project: Field water balance and its regulation techniques, water potential productivity and its prope
文摘The definition and classification of field evapotranspiration was discussed, based on which the calculation model for field evapotranspiration was established. Based on crop, soil measurements and mean climatic data in 1950-1980, mean field water surplus or deficit on climatic, crop and cropland basis in dryland of northern China was calculated, and the pattern of field water surplus or deficit was analyzed and discussed in this paper.
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 Key Project of National Social Science Fund(11&ZD042)"Research on Environmental Asset Accounting International Experience for Reference"of Ministry of Environmental Protection of the People's Republic of China(HBXM141116)
文摘This paper,based on the ecological footprint component method,calculated the touristic ecological footprint of Jiufeng National Forest Park in Beijing.The results showed that in 2013,in Jiufeng National Forest Park,the total touristic ecological footprint was 183.08 hm2,the total ecological capacity was 225.16 hm2,the total touristic ecological surplus was 42.07 hm2,and the average touristic ecological surplus was 0.000 4 hm2 per capita,indicating that tourism in Jiufeng National Forest Park was in ecological surplus and ecological security.However,forest parks in Beijing at large were in ecological deficit.This paper suggested that the tourist flow volume of forest parks with a big ecological deficit should be moved to forest parks with an ecological surplus.Besides,forest parks are expected to strengthen the development and management,improve the availability of forest recreation resource,and promote the environmental protection awareness of tourists,so as to boost the sustainable development of forest park tourism.
基金Under the auspices of National Natural Science Foundation of China(No.42201302)‘Double First-Class’University Construction Project of Lanzhou University(No.561120213)。
文摘Virtual water trade(VWT)provides a new perspective for alleviating water crisis and has thus attracted widespread attention.However,the heterogeneity of virtual water trade inside and outside the river basin and its influencing factors remains further study.In this study,for better investigating the pattern and heterogeneity of virtual water trade inside and outside provincial regions along the Yellow River Basin in 2015 using the input-output model(MRIO),we proposed two new concepts,i.e.,virtual water surplus and virtual water deficit,and then used the Logarithmic Mean Divisia Index(LMDI)model to identify the inherent mechanism of the imbalance of virtual water trade between provincial regions along the Yellow River Basin and the other four regions in China.The results show that:1)in provincial regions along the Yellow River Basin,the less developed the economy was,the larger the contribution of the agricultural sector in virtual water trade,while the smaller the contribution of the industrial sector.2)Due to the large output of agricultural products,the upstream and midstream provincial regions of the Yellow River Basin had a virtual water surplus,with a net outflow of virtual water of 2.7×10^(8) m^(3) and 0.9×10^(8) m^(3),respectively.3)provincial regions along the Yellow River Basin were in a virtual water deficit with the rest of China,and the decisive factor was the active degree of trade with the outside.This study would be beneficial to illuminate the trade-related water use issues in provincial regions along the Yellow River Basin,which has farreaching practical signific-ance for alleviating water scarcity.
基金Supported in part by the National Natural Science Foundation of China and the Ministry of Education of China
文摘We consider a continuous time risk model based on a two state Markov process, in which after an exponentially distributed time, the claim frequency changes to a different level and can change back again in the same way. We derive the Laplace transform for the first passage time to surplus zero from a given negative surplus and for the duration of negative surplus. Closed-form expressions are given in the case of exponential individual claim. Finally, numerical results are provided to show how to estimate the moments of duration of negative surplus.
基金Supported by the National Natural Science Foundation of China(11571198)the Tianyuan Fund for Mathematics(11226251)+3 种基金the Natural Science Foundation of Shandong(ZR2014AM021)the Natural Science Foundation of Qufu Normal University(2012ZRB01473)the Research Fund of Qufu Normal University for Doctor(BSQD2012039)the postdoctoral Foundation of Qufu Normal University
文摘In this paper, we study the risk model with Markovian arrivals where we allow the surplus process to continue if the surplus falls below zero. We first derive expressions for the severity of ruin. Then by using the strong Markovian property of a two-dimensional Markov process and the expression for the severity of ruin, we obtain the Laplace transform of the total duration of negative surplus.
文摘This paper explains the root cause of China＇s trade surplus and argues that it is rooted in structural factors. China＇s dual economic structure and the relatively slow growth in wages due to the abundant supply of labor have led to a large supply glut between China＇s domestic demand and output, which has been balanced by export. This is a structural problem that cannot be solved by currency appreciation or the readjustment of capital account deficits. A potentially viable option is to adjust the current account by developing a new opening-up system featuring more freedom and compliance.
