The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km2 in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional ...The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km2 in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain.Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas.After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert,we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water.The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition.The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession.The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.展开更多
A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependenci...A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China＇s ecological balance between supply and demand has become a global concern and is widely debated.In this study the ＇Ecological Footprint＇ method was used to analyze the supply-demand balance of China＇s ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index （ECCI） was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.展开更多
The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key fri...The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump.展开更多
As a concept to describe development restrictions,resources and environment carrying capacity（RECC）research has developed over more than 100 years since it was first proposed at the beginning of the 20th century.It ...As a concept to describe development restrictions,resources and environment carrying capacity（RECC）research has developed over more than 100 years since it was first proposed at the beginning of the 20th century.It is now regarded as a significant factor in evaluating the level of cooperation between regional population,resources,and environment;and it is currently used as an effective and operational tool to guide regional sustainable development.This article first reviews the origin of RECC and its early headway.It then reviews the historical development of RECC from single factors,such as land resources carrying capacity,water resources carrying capacity and environmental carrying capacity（environmental capacity）,to more comprehensive research,such as comprehensive evaluation,emergy analysis,and ecological footprint analysis.In general,it appears that comprehensive research will become increasingly important in RECC research.However,there are several deficiencies in the current state of comprehensive research.Firstly,comprehensive RECC research lacks a common measurement standard,though some scholars have attempted to create one.Secondly,the RECC evaluation of open systems and dynamic studies should be strengthened.Thirdly,more attention should be paid to standardization,digitalization,and systematization to promote the applicability of RECC research to national practical demands.展开更多
Land use intensity quantifies the impacts of human activities on natural ecosystems, which have become the major driver of global environmental change, and thus it serves as an essential measurement for assessing land...Land use intensity quantifies the impacts of human activities on natural ecosystems, which have become the major driver of global environmental change, and thus it serves as an essential measurement for assessing land use sustainability. To date, land-change studies have mainly focused on changes in land cover and their effects on ecological processes, whereas land use intensity has not yet received the attention it deserves and for which spa- tially-explicit representation studies have only just begun. In this paper, according to the de- gree and reversibility of surface disturbance by human activities, there are four main classes of land use intensity： artificial land, semi-artificial land, semi-natural land, and natural land. These were further divided into 22 subclasses based on key indicators, such as human pop- ulation density and the cropping intensity. Land use intensity map of China at a 1-km spatial resolution was obtained based on satellite images and statistical data. The area proportions of artificial land, semi-artificial land, semi-natural land, and natural land were 0.71%, 19.36%, 58.93%, and 21%, respectively. Human and economic carrying capacity increased with the increase of land use intensity. Artificial land supports 24.58% and 35.62% of the total population and GDP, using only 0.71% of the total land, while semi-artificial land supported 58.24% and 49.61% of human population and GDP with 19.36% of China＇s total land area.展开更多
Experimental researches were conducted on flood carrying capacity of compound open channels with wide and narrow floodplains as well as hydrodynamic behavior of overbank flow across vegetated floodplains. Results show...Experimental researches were conducted on flood carrying capacity of compound open channels with wide and narrow floodplains as well as hydrodynamic behavior of overbank flow across vegetated floodplains. Results show that hydrodynamic behavior of compound channels with narrow floodplains is different from that of the wide floodplains. In such compound channels with narrow vegetated floodplains as in the Pearl River delta nework, it has been found that vegetated domains become really impenetra ble when the length of vegetated domain is larger than Lm, the length of f low in floodplain coming into the main channel, and that the influence of vegeta ted floodplains upon flood stages of a channel is not very significant.展开更多
With the intensive research into global coupling relationships,ecological carrying capacity（ECC）,seen as the crucial link between natural ecosystems and human systems,has gradually become an important tool for inter...With the intensive research into global coupling relationships,ecological carrying capacity（ECC）,seen as the crucial link between natural ecosystems and human systems,has gradually become an important tool for interdisciplinary research in ecology,resources science and environmental science,as well as for research on regional sustainable development.However,ECC research remains immature and lacks a complete theoretical system,as a result of many limiting factors and different space-time conditions.At present,Chinese and foreign studies focus on methods to evaluate ECC while neglecting to identify the internal driving mechanisms of ECC.In this article,based on the development and conceptualization of ECC,we introduce three evaluation methods for ECC：ecological footprint（EF）,human appropriation of net primary production（HANPP）and ecosystem services consumption（ESC）.Furthermore,we illuminate research focuses and developmental directions for ECC with respect to driving mechanisms,threshold,comprehensive evaluation systems and coupling dynamic model of multi ecological factors,in order to provide a reference for future ECC research.展开更多
Quantitative assessment of development sustainability could be a challenge to regional management and planning, especially for areas facing great risks of water shortage. Surface-water decline and groundwater over-pum...Quantitative assessment of development sustainability could be a challenge to regional management and planning, especially for areas facing great risks of water shortage. Surface-water decline and groundwater over-pumping have caused serious environmental problems and limited economic development in many regions all around the world. In this paper, a framework for quantitatively evaluating development sustainability was established with water-related eco-environmental carrying capacity （EECC） as the core measure. As a case study, the developed approach was applied to data of the Haihe River Basin, China, during 1998 through 2007. The overall sustainable development degree （SDD） is determined to be 0.39, suggesting that this rate of development is not sustainable. Results of scenario analysis revealed that overshoot, or resource over- exploitation, of the Basin＇s EECC is about 20% for both population and economy. Based on conditions in the study area in 2007, in order to achieve sustainable development, i.e., SDD〉0.70 in this study, the EECC could support a population of 108 million and gross domestic product （GDP） of 2.72 trillion CNY. The newly developed approach in quantifying ecoenvironmental carrying capacity is anticipated to facilitate sustainable development oriented resource management in waterdeficient areas.展开更多
Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use control.Resource allocations and environmental capacity are the basic conditions that restrict devel...Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use control.Resource allocations and environmental capacity are the basic conditions that restrict development in a region.In this paper,based on a systematic review of China's geological environment,groundwater resources,mineral resources,other geological resources and the environmental carrying capacity research status,the relationship between the natural resource environmental system and the socio-economic system is studied.Then a "coordination theory of resources and environmental carrying"is proposed.Next,on the basis of an evaluation experiment performed at different scales and for different types of regions,the technical methods for an evaluation of the geological resources and environmental carrying capacity at the regional (inter-provincial)and provincial scales in China are established for the first time.This paper presents a standardized method based on technical ideas, evaluation methods,and index systems for geological resource and environmental carrying capacity evaluation.Finally,an evaluation of the groundwater resource carrying capacity in China is used as an example for the demonstration of the groundwater resource background and use of state evaluation methods.展开更多
Forests play an important role in acting as a carbon sink of terrestrial ecosystem.Although global forests have huge carbon carrying capacity(CCC)and carbon sequestration potential(CSP),there were few quantification r...Forests play an important role in acting as a carbon sink of terrestrial ecosystem.Although global forests have huge carbon carrying capacity(CCC)and carbon sequestration potential(CSP),there were few quantification reports on Chinese forests.We collected and compiled a forest biomass dataset of China,a total of 5841 sites,based on forest inventory and literature search results.From the dataset we extracted 338 sites with forests aged over 80 years,a threshold for defining mature forest,to establish the mature forest biomass dataset.After analyzing the spatial pattern of the carbon density of Chinese mature forests and its controlling factors,we used carbon density of mature forests as the reference level,and conservatively estimated the CCC of the forests in China by interpolation methods of Regression Kriging,Inverse Distance Weighted and Partial Thin Plate Smoothing Spline.Combining with the sixth National Forest Resources Inventory,we also estimated the forest CSP.The results revealed positive relationships between carbon density of mature forests and temperature,precipitation and stand age,and the horizontal and elevational patterns of carbon density of mature forests can be well predicted by temperature and precipitation.The total CCC and CSP of the existing forests are 19.87 and 13.86 Pg C,respectively.Subtropical forests would have more CCC and CSP than other biomes.Consequently,relying on forests to uptake carbon by decreasing disturbance on forests would be an alternative approach for mitigating greenhouse gas concentration effects besides afforestation and reforestation.展开更多
As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resour...As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resources. Beijing, the second-largest city in China, faces a critical water shortage that will limit the city’s future development. We developed a method to quantify the carrying capacity of Beijing’s water resources by considering water-use structures based on the proportions of water used for agricultural, industrial, and domestic purposes. We defined a reference structure as 45：22：33 （% of total, respectively）, an optimized structure as 40：20：40, and an ideal structure as 50：15：35. We also considered four domestic water quotas： 55, 75, 95, and 115 m 3 /（person·yr）. The urban carrying capacity of 10–12 million was closest to Beijing’s actual 2003 population for all three water-use structures with urban domestic water use of 75 m 3 /（person·yr）. However, after accounting for our underlying assumptions, the adjusted carrying capacity is closer to 5–6 million. Thus, Beijing’s population in 2003 was almost twice the adjusted carrying capacity. Based on this result, we discussed the ecological and environmental problems created by Beijing’s excessive population and propose measures to mitigate these problems.展开更多
A model of Suzhou water resources carrying capacity （WRCC） was set up using the method of system dynamics （SD）. In the model, three different water resources utilization programs were adopted： （1） continuity of...A model of Suzhou water resources carrying capacity （WRCC） was set up using the method of system dynamics （SD）. In the model, three different water resources utilization programs were adopted： （1） continuity of existing water utilization, （2） water conservation/saving, and （3） water exploitation. The dynamic variation of the Suzhou WRCC was simulated with the supply-decided principle for the time period of 2001 to 2030, and the results were characterized based on socio-economic factors. The corresponding Suzhou WRCC values for several target years were calculated by the model. Based on these results, proper ways to improve the Suzhou WRCC are proposed. The model also produced an optimized plan, which can provide a scientific basis for the sustainable utilization of Suzhou water resources and for the coordinated development of the society, economy, and water resources.展开更多
Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereaf...Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereafter referred to as the Technical Outline),this paper elaborates on the collection and sorting of the basic data of water resources conditions,water resources development and utilization status,social and economic development in basins,analysis and examination of integrity,consistency,normativeness,and rationality of the basic data,and the necessity of WRCC evaluation.This paper also describes the technique of evaluating the WRCC in prefecture-level cities and city-level administrative divisions in the District of the Taihu Lake Basin,which is composed of the Taihu Lake Basin and the Southeastern River Basin.The evaluation process combines the binary index evaluation method and reduction index evaluation method.The former,recommended by the Technical Outline,uses the total water use and the amount of exploited groundwater as evaluation indices,showing stronger operability,while the latter is developed by simplifying and optimizing the comprehensive index system with greater systematicness and completeness.The mutual validation and adjustment of the results of the above-mentioned two evaluation methods indicate that the WRCC of the District of the Taihu Lake Basin is overloaded in general because some prefecture-level cities and city-level administrative divisions in the Taihu Lake Basin and the Southeastern River Basin are in a severely overloaded state.In order to explain this conclusion,this paper analyzes the causes of WRCC overloading from the aspects of basin water environment,water resources development and utilization,water resources regulation and control ability,water resources utilization efficiency,and water resources management.展开更多
As an important part of resource and environment carrying capacity（RECC）,land resource carrying capacity（LRCC） has focused on the limiting factors on regional development from the scale of land resources for more ...As an important part of resource and environment carrying capacity（RECC）,land resource carrying capacity（LRCC） has focused on the limiting factors on regional development from the scale of land resources for more than two hundred years.After a brief review of the origin and early development of LRCC,the progress of LRCC is summarized as a progression from land resource population carrying capacity（LPCC） to land resource comprehensive carrying capacity（LCCC）,and the hot issues of LRCC have changed from the simple human–grain relationship to more complex social and economic activities–land resources relationships.The corresponding research methods also evolved,from static research to dynamic research,and the assessment factor have evolved from a single factor to a comprehensive index system.Agro-ecological zoning（AEZ）,system dynamics（SD）,ecological footprint（EF）,and comprehensive evaluation methods have come to be viewed as the most representative methods of LRCC in recent years.As a focus of conventional LRCC research,the human–grain relationship still plays a significant role in LRCC evaluation because grain remains the top limiting factor of land resources and is the most significant criterion in the balance between regional population and land resources,especially for very populous countries.More attention should be paid to the accurate calculation of arable land and average food consumption levels to improve the scientific basis of LRCC evaluation.The development of science and technology and the variation of lifestyle are also important factors that influence regional LRCC.As a new topic of LRCC,LCCC has expanded the research field of LRCC in an attempt to reveal the limiting effects of land resource under open systems,but some issues such as carrying mechanism research and the combination of theoretical and applied research are needed in future studies to promote the further development of LCCC.展开更多
基金supported by the National Basic Research Program of China(2013CB429906)
文摘The main prevention and control area for wind-blown sand hazards in northern China is about 320000 km2 in size and includes sandlands to the east of the Helan Mountain and sandy deserts and desert-steppe transitional regions to the west of the Helan Mountain.Vegetation recovery and restoration is an important and effective approach for constraining wind-blown sand hazards in these areas.After more than 50 years of long-term ecological studies in the Shapotou region of the Tengger Desert,we found that revegetation changed the hydrological processes of the original sand dune system through the utilization and space-time redistribution of soil water.The spatiotemporal dynamics of soil water was significantly related to the dynamics of the replanted vegetation for a given regional precipitation condition.The long-term changes in hydrological processes in desert areas also drive replanted vegetation succession.The soil water carrying capacity of vegetation and the model for sand fixation by revegetation in aeolian desert areas where precipitation levels are less than 200 mm are also discussed.
基金National Natural Science Foundation of China, No.40801223 Research Project by Department ot Servlces and Management for Floating Population, Ministry of National Population and Family Planning Commission ofP. R. China （2010-11）
文摘A balanced ecological carrying capacity and its understanding are important to achieve sustainable development for human kind.Here,the concept of ecological carrying capacity has been used for measuring the dependencies between human and nature.China＇s ecological balance between supply and demand has become a global concern and is widely debated.In this study the ＇Ecological Footprint＇ method was used to analyze the supply-demand balance of China＇s ecological carrying capacity.Firstly,the ecological supply and demand balance was calculated and evaluated,and secondly,the ecological carrying capacity index （ECCI） was derived for each county of China in 2007,and finally this paper systematically evaluated the ecological carrying capacity supply-demand balance of China.The results showed that ecological deficit appeared to be the main characteristic of ecological carrying capacity supply-demand balance in 2007 of China at county scale.In general,more than four-fifths of the Chinese population was concentrated in less than one-third of the land area and more than two-thirds of the land area was inhabited by less than one-fifth of the population.The spatial distribution of the ecological carrying capacity demand-supply was unbalanced ranging from significant overloading to affluence from southeastern to northwestern part of China.It appeared to be more dominant in regions located at coastal areas which are attracted by migrants and had a generally higher population density.Along with the rapid development and urbanization trends in China,ecological deficits in these regions will become more severe.
基金supported by National Natural Science Foundation of China(Grant No. 51075360)Doctoral Foundation of Ministry of Education of China(Grant No. 20090101110041)National Key Technology R&D Program of the Twelfth Five-year Plan of China(Grant No. 2011BAF09B03)
文摘The limit working parameters and service life of axial piston pump are determined by the carrying ability and lubrication characteristic of its key friction pairs. Therefore, the design and optimization of the key friction pairs are always a key and difficult problem in the research on axial piston pump. In the traditional research on piston/cylinder pair, the assembly relationship of piston and cylinder bore is simplified into ideal cylindrical pair, which can not be used to analyze the influences of radial micro-motion of piston on the distribution characteristics of oil-film thickness and pressure in details. In this paper, based on the lubrication theory of the oil film, a numerical simulation model is built, taking the influences of roughness, elastic deformation of piston and pressure-viscosity effect into consideration. With the simulation model, the dynamic characteristics of the radial micro-motion and pressure distribution are analyzed, and the relationships between radial micro-motion and carrying ability, lubrication condition, and abrasion are discussed. Furthermore, a model pump for pressure distribution measurement of oil film between piston and cylinder bore is designed. The comparison of simulation and experimental results of pressure distribution shows that the simulation model has high accuracy. The experiment and simulation results demonstrate that the pressure distribution has peak values that are much higher than the boundary pressure in the piston chamber due to the radial micro-motion, and the abrasion of piston takes place mainly on the hand close to piston ball. In addition, improvement of manufacturing roundness and straightness of piston and cylinder bore is helpful to improve the carrying ability of piston/cylinder pair. The proposed research provides references for designing piston/cylinder pair, and helps to prolong the service life of axial piston pump.
基金The National Key Research and Development Program of China(2016YFC0503500)National Science and Technology Major Project(Z2016C01G01)
文摘As a concept to describe development restrictions,resources and environment carrying capacity（RECC）research has developed over more than 100 years since it was first proposed at the beginning of the 20th century.It is now regarded as a significant factor in evaluating the level of cooperation between regional population,resources,and environment;and it is currently used as an effective and operational tool to guide regional sustainable development.This article first reviews the origin of RECC and its early headway.It then reviews the historical development of RECC from single factors,such as land resources carrying capacity,water resources carrying capacity and environmental carrying capacity（environmental capacity）,to more comprehensive research,such as comprehensive evaluation,emergy analysis,and ecological footprint analysis.In general,it appears that comprehensive research will become increasingly important in RECC research.However,there are several deficiencies in the current state of comprehensive research.Firstly,comprehensive RECC research lacks a common measurement standard,though some scholars have attempted to create one.Secondly,the RECC evaluation of open systems and dynamic studies should be strengthened.Thirdly,more attention should be paid to standardization,digitalization,and systematization to promote the applicability of RECC research to national practical demands.
基金National Key Research and Development Program of China,No.2016YFC0503500,No.2016YFC0503700
文摘Land use intensity quantifies the impacts of human activities on natural ecosystems, which have become the major driver of global environmental change, and thus it serves as an essential measurement for assessing land use sustainability. To date, land-change studies have mainly focused on changes in land cover and their effects on ecological processes, whereas land use intensity has not yet received the attention it deserves and for which spa- tially-explicit representation studies have only just begun. In this paper, according to the de- gree and reversibility of surface disturbance by human activities, there are four main classes of land use intensity： artificial land, semi-artificial land, semi-natural land, and natural land. These were further divided into 22 subclasses based on key indicators, such as human pop- ulation density and the cropping intensity. Land use intensity map of China at a 1-km spatial resolution was obtained based on satellite images and statistical data. The area proportions of artificial land, semi-artificial land, semi-natural land, and natural land were 0.71%, 19.36%, 58.93%, and 21%, respectively. Human and economic carrying capacity increased with the increase of land use intensity. Artificial land supports 24.58% and 35.62% of the total population and GDP, using only 0.71% of the total land, while semi-artificial land supported 58.24% and 49.61% of human population and GDP with 19.36% of China＇s total land area.
文摘Experimental researches were conducted on flood carrying capacity of compound open channels with wide and narrow floodplains as well as hydrodynamic behavior of overbank flow across vegetated floodplains. Results show that hydrodynamic behavior of compound channels with narrow floodplains is different from that of the wide floodplains. In such compound channels with narrow vegetated floodplains as in the Pearl River delta nework, it has been found that vegetated domains become really impenetra ble when the length of vegetated domain is larger than Lm, the length of f low in floodplain coming into the main channel, and that the influence of vegeta ted floodplains upon flood stages of a channel is not very significant.
基金The National Key Research and Development Program of China(2016YFC0503500)National Science and Technology Major Project(Z2016C01G01)
文摘With the intensive research into global coupling relationships,ecological carrying capacity（ECC）,seen as the crucial link between natural ecosystems and human systems,has gradually become an important tool for interdisciplinary research in ecology,resources science and environmental science,as well as for research on regional sustainable development.However,ECC research remains immature and lacks a complete theoretical system,as a result of many limiting factors and different space-time conditions.At present,Chinese and foreign studies focus on methods to evaluate ECC while neglecting to identify the internal driving mechanisms of ECC.In this article,based on the development and conceptualization of ECC,we introduce three evaluation methods for ECC：ecological footprint（EF）,human appropriation of net primary production（HANPP）and ecosystem services consumption（ESC）.Furthermore,we illuminate research focuses and developmental directions for ECC with respect to driving mechanisms,threshold,comprehensive evaluation systems and coupling dynamic model of multi ecological factors,in order to provide a reference for future ECC research.
基金funding support from the Key Knowledge Innovation Project of the Chinese Academy of Sciences(Kzcx2-yw-126)the Key Technology R&D Program of China(2006BAB14B07)the National Natural Sciences Foundation of China(40730632,40701027)
文摘Quantitative assessment of development sustainability could be a challenge to regional management and planning, especially for areas facing great risks of water shortage. Surface-water decline and groundwater over-pumping have caused serious environmental problems and limited economic development in many regions all around the world. In this paper, a framework for quantitatively evaluating development sustainability was established with water-related eco-environmental carrying capacity （EECC） as the core measure. As a case study, the developed approach was applied to data of the Haihe River Basin, China, during 1998 through 2007. The overall sustainable development degree （SDD） is determined to be 0.39, suggesting that this rate of development is not sustainable. Results of scenario analysis revealed that overshoot, or resource over- exploitation, of the Basin＇s EECC is about 20% for both population and economy. Based on conditions in the study area in 2007, in order to achieve sustainable development, i.e., SDD〉0.70 in this study, the EECC could support a population of 108 million and gross domestic product （GDP） of 2.72 trillion CNY. The newly developed approach in quantifying ecoenvironmental carrying capacity is anticipated to facilitate sustainable development oriented resource management in waterdeficient areas.
基金the Program of the Geological Survey of China (DD20160328)the National Science Foundation of China (41702386).
文摘Evaluations of resources and environmental carrying capacities (GRECC)are the premise of land space planning and use control.Resource allocations and environmental capacity are the basic conditions that restrict development in a region.In this paper,based on a systematic review of China's geological environment,groundwater resources,mineral resources,other geological resources and the environmental carrying capacity research status,the relationship between the natural resource environmental system and the socio-economic system is studied.Then a "coordination theory of resources and environmental carrying"is proposed.Next,on the basis of an evaluation experiment performed at different scales and for different types of regions,the technical methods for an evaluation of the geological resources and environmental carrying capacity at the regional (inter-provincial)and provincial scales in China are established for the first time.This paper presents a standardized method based on technical ideas, evaluation methods,and index systems for geological resource and environmental carrying capacity evaluation.Finally,an evaluation of the groundwater resource carrying capacity in China is used as an example for the demonstration of the groundwater resource background and use of state evaluation methods.
基金supported by the National Basic Research Program of China(2010CB833504)the CAS Strategic Priority Research Program(XDA05050702)the National Natural Science Foundation of China(31290221)
文摘Forests play an important role in acting as a carbon sink of terrestrial ecosystem.Although global forests have huge carbon carrying capacity(CCC)and carbon sequestration potential(CSP),there were few quantification reports on Chinese forests.We collected and compiled a forest biomass dataset of China,a total of 5841 sites,based on forest inventory and literature search results.From the dataset we extracted 338 sites with forests aged over 80 years,a threshold for defining mature forest,to establish the mature forest biomass dataset.After analyzing the spatial pattern of the carbon density of Chinese mature forests and its controlling factors,we used carbon density of mature forests as the reference level,and conservatively estimated the CCC of the forests in China by interpolation methods of Regression Kriging,Inverse Distance Weighted and Partial Thin Plate Smoothing Spline.Combining with the sixth National Forest Resources Inventory,we also estimated the forest CSP.The results revealed positive relationships between carbon density of mature forests and temperature,precipitation and stand age,and the horizontal and elevational patterns of carbon density of mature forests can be well predicted by temperature and precipitation.The total CCC and CSP of the existing forests are 19.87 and 13.86 Pg C,respectively.Subtropical forests would have more CCC and CSP than other biomes.Consequently,relying on forests to uptake carbon by decreasing disturbance on forests would be an alternative approach for mitigating greenhouse gas concentration effects besides afforestation and reforestation.
基金supported by the Knowledge InnovationProject of the Chinese Academy of Sciences (No. KZCX2-YW-422)
文摘As the demands on limited water resources intensify, concerns are being raised about the human carrying capacity of these resources. However, few researchers have studied the carrying capacity of regional water resources. Beijing, the second-largest city in China, faces a critical water shortage that will limit the city’s future development. We developed a method to quantify the carrying capacity of Beijing’s water resources by considering water-use structures based on the proportions of water used for agricultural, industrial, and domestic purposes. We defined a reference structure as 45：22：33 （% of total, respectively）, an optimized structure as 40：20：40, and an ideal structure as 50：15：35. We also considered four domestic water quotas： 55, 75, 95, and 115 m 3 /（person·yr）. The urban carrying capacity of 10–12 million was closest to Beijing’s actual 2003 population for all three water-use structures with urban domestic water use of 75 m 3 /（person·yr）. However, after accounting for our underlying assumptions, the adjusted carrying capacity is closer to 5–6 million. Thus, Beijing’s population in 2003 was almost twice the adjusted carrying capacity. Based on this result, we discussed the ecological and environmental problems created by Beijing’s excessive population and propose measures to mitigate these problems.
基金supported by the National Natural Science Foundation of China (Grant No.50638020)
文摘A model of Suzhou water resources carrying capacity （WRCC） was set up using the method of system dynamics （SD）. In the model, three different water resources utilization programs were adopted： （1） continuity of existing water utilization, （2） water conservation/saving, and （3） water exploitation. The dynamic variation of the Suzhou WRCC was simulated with the supply-decided principle for the time period of 2001 to 2030, and the results were characterized based on socio-economic factors. The corresponding Suzhou WRCC values for several target years were calculated by the model. Based on these results, proper ways to improve the Suzhou WRCC are proposed. The model also produced an optimized plan, which can provide a scientific basis for the sustainable utilization of Suzhou water resources and for the coordinated development of the society, economy, and water resources.
基金supported by the National Natural Science Foundation of China(Grant No.51379181)Phase Ⅲ Project(2018-2021)of the Priority Academic Program Development of Jiangsu Higher Education Institutions
文摘Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereafter referred to as the Technical Outline),this paper elaborates on the collection and sorting of the basic data of water resources conditions,water resources development and utilization status,social and economic development in basins,analysis and examination of integrity,consistency,normativeness,and rationality of the basic data,and the necessity of WRCC evaluation.This paper also describes the technique of evaluating the WRCC in prefecture-level cities and city-level administrative divisions in the District of the Taihu Lake Basin,which is composed of the Taihu Lake Basin and the Southeastern River Basin.The evaluation process combines the binary index evaluation method and reduction index evaluation method.The former,recommended by the Technical Outline,uses the total water use and the amount of exploited groundwater as evaluation indices,showing stronger operability,while the latter is developed by simplifying and optimizing the comprehensive index system with greater systematicness and completeness.The mutual validation and adjustment of the results of the above-mentioned two evaluation methods indicate that the WRCC of the District of the Taihu Lake Basin is overloaded in general because some prefecture-level cities and city-level administrative divisions in the Taihu Lake Basin and the Southeastern River Basin are in a severely overloaded state.In order to explain this conclusion,this paper analyzes the causes of WRCC overloading from the aspects of basin water environment,water resources development and utilization,water resources regulation and control ability,water resources utilization efficiency,and water resources management.
基金National Key Research and Development Program of China(2016YFC0503500)National Science and Technology Major Project(Z2016C01G01)National Natural Science Foundation of China(41471453)
文摘As an important part of resource and environment carrying capacity（RECC）,land resource carrying capacity（LRCC） has focused on the limiting factors on regional development from the scale of land resources for more than two hundred years.After a brief review of the origin and early development of LRCC,the progress of LRCC is summarized as a progression from land resource population carrying capacity（LPCC） to land resource comprehensive carrying capacity（LCCC）,and the hot issues of LRCC have changed from the simple human–grain relationship to more complex social and economic activities–land resources relationships.The corresponding research methods also evolved,from static research to dynamic research,and the assessment factor have evolved from a single factor to a comprehensive index system.Agro-ecological zoning（AEZ）,system dynamics（SD）,ecological footprint（EF）,and comprehensive evaluation methods have come to be viewed as the most representative methods of LRCC in recent years.As a focus of conventional LRCC research,the human–grain relationship still plays a significant role in LRCC evaluation because grain remains the top limiting factor of land resources and is the most significant criterion in the balance between regional population and land resources,especially for very populous countries.More attention should be paid to the accurate calculation of arable land and average food consumption levels to improve the scientific basis of LRCC evaluation.The development of science and technology and the variation of lifestyle are also important factors that influence regional LRCC.As a new topic of LRCC,LCCC has expanded the research field of LRCC in an attempt to reveal the limiting effects of land resource under open systems,but some issues such as carrying mechanism research and the combination of theoretical and applied research are needed in future studies to promote the further development of LCCC.
