Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of...Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of resource-exhausted cities.Using 23 indicators,this study evaluated the ecological security status and development trends of 21 resource-exhausted cities in China from 2011 to 2017.The results showed that from 2011 to 2015,the overall ecological security of this type of city was low,with over 60%of the cities at an unsafe level.However,ecological security improved rapidly after 2016,and by 2017,all of the cities had reached the critical safety level.The top 10 indicators of ecological security included industrial sulfur dioxide emissions,water supply,agricultural fertilizer application,and forest coverage.These 10 indicators’cumulative contribution to ecological security was 48.3%;among them,reducing industrial sulfur dioxide emissions contributed the most at 5.7%.These findings can help governments better understand the ecological security status of resource-exhausted cities,and it can provide a reference for the allocation of funds and other resources to improve the ecological safety of these cities.展开更多
Analyzing agricultural sustainability is essential for designing and assessing rural development initiatives.However,accurately measuring agricultural sustainability is complicated since it involves so many different ...Analyzing agricultural sustainability is essential for designing and assessing rural development initiatives.However,accurately measuring agricultural sustainability is complicated since it involves so many different factors.This study provides a new suite of quantitative indicators for assessing agricultural sustainability at regional and district levels,involving environmental sustainability,social security,and economic security.Combining the PressureState-Response(PSR)model and indicator approach,this study creates a composite agricultural sustainability index for the 14 mainstream agro-climatic regions of India.The results of this study show that the Trans-Gengatic Plain Region(TGPR)ranks first in agricultural sustainability among India's 14 mainstream agro-climatic regions,while the Eastern Himalayan Region(EHR)ranks last.Higher livestock ownership,cropping intensity,per capita income,irrigation intensity,share of institutional credit,food grain productivity,crop diversification,awareness of minimum support price,knowledge sharing with fellow farmers,and young and working population,as well as better transportation facilities and membership of agricultural credit societies are influencing indicators responsible for higher agricultural sustainability in TGPR compared with EHR.Although,the scores of environmental sustainability indicators of EHR are quite good,its scores of social and economic security indicators are fairly low,putting it at the bottom of the rank of agricultural sustainability index among the 14 mainstream agroclimatic regions in India.This demonstrates the need of understanding agricultural sustainability in relation to social and economic dimensions.In a nation as diverse and complicated as India,it is the social structure that determines the health of the economy and environment.Last but not least,the sustainability assessment methodology may be used in a variety of India's agro-climatic regions.展开更多
Copper metal is one important raw material of national economy, and its security is tightly linked with industrialization process. A comprehensive security evaluation index system, including three first class indicato...Copper metal is one important raw material of national economy, and its security is tightly linked with industrialization process. A comprehensive security evaluation index system, including three first class indicators, nine second class indicators and fourteen third class indicators, was constructed based on the pressure-state-response (PSR) model. And efficacy coeff^cient method was adopted in dimensionless treatment and entropy method was used to obtain the weight. Then, the data of China's copper from 1992 to 2011 were studied and collected. By processing these data, a comprehensive safety index of China's copper was got. The results showed that the comprehensive safety index of China's copper rose from its low point. The safety pressure state of China's copper was improved. The safety state of China's copper continued to be tight. The response state continued to rise. The overall situation of China's copper safety was improving, but still not optimistic.展开更多
In order to study the indentation size effect(ISE)of germanium single crystals,nano-indentation experiments were carried out on the(100),(110)and(111)plane-orientated germanium single crystals.The true hardness of eac...In order to study the indentation size effect(ISE)of germanium single crystals,nano-indentation experiments were carried out on the(100),(110)and(111)plane-orientated germanium single crystals.The true hardness of each crystal plane of germanium single crystals was calculated based on the Meyer equation,proportional sample resistance(PSR)model and Nix-Gao model,and the indentation size effect(ISE)factor of each crystal plane was calculated.Results show that,the germanium single crystals experience elastic deformation,plastic deformation and brittle fracture during the loading process,and the three crystal planes all show obvious ISE phenomenon.All three models can effectively describe the ISE of germanium single crystals,and the calculated value of Nix-Gao model is the most accurate.Compared with the other two crystal planes,Ge(110)has the highest size effect factor m and the highest hardness,which indicates that Ge(110)has the worst plasticity.展开更多
Land use change has significant influence on the operation of the PopulationResources-Environment-De-velopment (PRED) System. Moderate land use is the key factor to ensure the coordinative and sustainable development ...Land use change has significant influence on the operation of the PopulationResources-Environment-De-velopment (PRED) System. Moderate land use is the key factor to ensure the coordinative and sustainable development between land use and PRED system. Based on the internal relationship between land use and PRED system, a PRED evaluation index system and a Press-Status-Response (PSR) model were established in this study. According to the expounding on the mechanism of the PSR model, we investigated the coordinative development between the changes of regional land use and PRED system taking Jiangsu Province as an example. The results showed that the orders of the Synthetic Index of Land Use (SILU) and the Variation of PRED Index (VPI) in Jiangsu are both the southern Jiangsu>the central Jiangsu>the northern Jiangsu. A cubic curve model was used to fit the relationship between the VPI and SILU. The inflection point of VPI was situated in 5.0 of SILU. When SILU was below 5.0, VPI increased with SILU, which will be helpful to the coordinative development between land use and PRED system. Based on those results, it is suggested that the land use degree of the southern Jiangsu, especially that of Nanjing City, should be moderately controlled at present, while land resources of the central Jiangsu and the northern Jiangsu should be further exploited.展开更多
By analyzing current situation of the Caihai Wetland, combining with "3S" technology, theory of ecosystem health, landscape ecology theory, applying the model of Pressure–State–Response, this paper assesse...By analyzing current situation of the Caihai Wetland, combining with "3S" technology, theory of ecosystem health, landscape ecology theory, applying the model of Pressure–State–Response, this paper assessed dynamic changes of ecological frangibility of the Caohai Wetland in Guizhou in 1992, 2000 and 2013. The results showed that the wetland ecosystem had sound principal functions, but also witnessed different degrees of degradation. The ratio of basic complete ecosystem landscape area in the Caohai Wetland reduced from 70.56% in 1992 to 66.26% in 2013, and the ratio of destructed landscape area increased from 12.11% in 1992 to 13.38% in 2013.展开更多
In this paper, the major objective is to build a global dynamic network model to assess the global health condition .First use the PSR model and Analytic hierarchy process (AHP) to calculate the internal health stat...In this paper, the major objective is to build a global dynamic network model to assess the global health condition .First use the PSR model and Analytic hierarchy process (AHP) to calculate the internal health status of some regions, and then establish a global network model which links each region together to figure out the global health status. Finally, taking the human influence into consideration, the degree of the earth's health can be figured out in a more accurate way.展开更多
Along with the rapid development of port building, the negative impacts of port's construction and operation on the coastline ecosystem are also increasingly strong. Therefore, it's urgent to establish a scientific ...Along with the rapid development of port building, the negative impacts of port's construction and operation on the coastline ecosystem are also increasingly strong. Therefore, it's urgent to establish a scientific and complete system of port ecological suitability evaluation. This paper pointed out the characteristics of port ecological effects and the principles of selecting evaluation index, and used the "pressure-state-response (PSR)" model to analysis the various pressures on the environment caused by port construction and operation, and the system's response. On this basis, we constructed the port ecological suitability evaluation index. This model used the combination of qualitative and quantitative analytic hierarchy process, to meet the multi-level, multi-objective characteristics of evaluation index system. The evaluation index system and evaluation model can be used to analysis the ecological suitability of port projects comprehensively and have some guiding significance to the port ecological suitability evaluation.展开更多
Africa,the second largest continent in the world,has achieved remarkable economic and political results through exploration and positive development.Ecological security comprehensively reflects the health and integrit...Africa,the second largest continent in the world,has achieved remarkable economic and political results through exploration and positive development.Ecological security comprehensively reflects the health and integrity of an ecosystem,and it is broadly defined as the security state of a complex artificial ecosystem composed of natural,economic and social factors.Ecological security determines the potential for sustainable development in Africa,especially with its rapidly developing economies.However,there is a lack of information on the ecological security state of the continent as a whole.In this study,we constructed an evaluation system based on a pressure-state-response model and evaluated the ecological security state of all 54 African countries.The results showed that,at the national level,the ecological security state of the countries in Africa differed,as did their spatial and temporal variations from 1995 to 2016.In general,African countries showed relatively good ecological security.The years 2007 and 2001 were the worst and best years,respectively,in terms of ecological security during the study period.At the regional level,North Africa andWest Africa had the best and worst ecological security,respectively.展开更多
基金This work was supported by the Technology R&D Program of Changsha City(nos.kc1702045 and kq1901145)the Key Technology R&D Program of Hunan Province(nos.2016TP2007,2017TP2006,and 2016TP1014).
文摘Today,resource depletion threatens a number of resource-based cities in China.The ecological security problem caused by the long-term exploitation of natural resources is a key issue to be solved in the development of resource-exhausted cities.Using 23 indicators,this study evaluated the ecological security status and development trends of 21 resource-exhausted cities in China from 2011 to 2017.The results showed that from 2011 to 2015,the overall ecological security of this type of city was low,with over 60%of the cities at an unsafe level.However,ecological security improved rapidly after 2016,and by 2017,all of the cities had reached the critical safety level.The top 10 indicators of ecological security included industrial sulfur dioxide emissions,water supply,agricultural fertilizer application,and forest coverage.These 10 indicators’cumulative contribution to ecological security was 48.3%;among them,reducing industrial sulfur dioxide emissions contributed the most at 5.7%.These findings can help governments better understand the ecological security status of resource-exhausted cities,and it can provide a reference for the allocation of funds and other resources to improve the ecological safety of these cities.
文摘Analyzing agricultural sustainability is essential for designing and assessing rural development initiatives.However,accurately measuring agricultural sustainability is complicated since it involves so many different factors.This study provides a new suite of quantitative indicators for assessing agricultural sustainability at regional and district levels,involving environmental sustainability,social security,and economic security.Combining the PressureState-Response(PSR)model and indicator approach,this study creates a composite agricultural sustainability index for the 14 mainstream agro-climatic regions of India.The results of this study show that the Trans-Gengatic Plain Region(TGPR)ranks first in agricultural sustainability among India's 14 mainstream agro-climatic regions,while the Eastern Himalayan Region(EHR)ranks last.Higher livestock ownership,cropping intensity,per capita income,irrigation intensity,share of institutional credit,food grain productivity,crop diversification,awareness of minimum support price,knowledge sharing with fellow farmers,and young and working population,as well as better transportation facilities and membership of agricultural credit societies are influencing indicators responsible for higher agricultural sustainability in TGPR compared with EHR.Although,the scores of environmental sustainability indicators of EHR are quite good,its scores of social and economic security indicators are fairly low,putting it at the bottom of the rank of agricultural sustainability index among the 14 mainstream agroclimatic regions in India.This demonstrates the need of understanding agricultural sustainability in relation to social and economic dimensions.In a nation as diverse and complicated as India,it is the social structure that determines the health of the economy and environment.Last but not least,the sustainability assessment methodology may be used in a variety of India's agro-climatic regions.
基金Projects(13BGL105,13&ZD024) supported by the National Social Science Foundation of ChinaProject(2013ZK2003) supported by the Major Soft Program of Hunan Province,China
文摘Copper metal is one important raw material of national economy, and its security is tightly linked with industrialization process. A comprehensive security evaluation index system, including three first class indicators, nine second class indicators and fourteen third class indicators, was constructed based on the pressure-state-response (PSR) model. And efficacy coeff^cient method was adopted in dimensionless treatment and entropy method was used to obtain the weight. Then, the data of China's copper from 1992 to 2011 were studied and collected. By processing these data, a comprehensive safety index of China's copper was got. The results showed that the comprehensive safety index of China's copper rose from its low point. The safety pressure state of China's copper was improved. The safety state of China's copper continued to be tight. The response state continued to rise. The overall situation of China's copper safety was improving, but still not optimistic.
基金Project(51765027)supported by the National Natural Science Foundation of China.
文摘In order to study the indentation size effect(ISE)of germanium single crystals,nano-indentation experiments were carried out on the(100),(110)and(111)plane-orientated germanium single crystals.The true hardness of each crystal plane of germanium single crystals was calculated based on the Meyer equation,proportional sample resistance(PSR)model and Nix-Gao model,and the indentation size effect(ISE)factor of each crystal plane was calculated.Results show that,the germanium single crystals experience elastic deformation,plastic deformation and brittle fracture during the loading process,and the three crystal planes all show obvious ISE phenomenon.All three models can effectively describe the ISE of germanium single crystals,and the calculated value of Nix-Gao model is the most accurate.Compared with the other two crystal planes,Ge(110)has the highest size effect factor m and the highest hardness,which indicates that Ge(110)has the worst plasticity.
基金Under the auspices of National Natural Science Foundation of China (No. 70373029)Ministry of Education Plans to Support the New Century Talents (No. NCET-05-0451)
文摘Land use change has significant influence on the operation of the PopulationResources-Environment-De-velopment (PRED) System. Moderate land use is the key factor to ensure the coordinative and sustainable development between land use and PRED system. Based on the internal relationship between land use and PRED system, a PRED evaluation index system and a Press-Status-Response (PSR) model were established in this study. According to the expounding on the mechanism of the PSR model, we investigated the coordinative development between the changes of regional land use and PRED system taking Jiangsu Province as an example. The results showed that the orders of the Synthetic Index of Land Use (SILU) and the Variation of PRED Index (VPI) in Jiangsu are both the southern Jiangsu>the central Jiangsu>the northern Jiangsu. A cubic curve model was used to fit the relationship between the VPI and SILU. The inflection point of VPI was situated in 5.0 of SILU. When SILU was below 5.0, VPI increased with SILU, which will be helpful to the coordinative development between land use and PRED system. Based on those results, it is suggested that the land use degree of the southern Jiangsu, especially that of Nanjing City, should be moderately controlled at present, while land resources of the central Jiangsu and the northern Jiangsu should be further exploited.
基金Sponsored by National Natural Science Foundation of China(41161002)Guizhou Province Governor Foundation(2011No.46)Guizhou Project of Ministry of Environmental Protection"RS Survey and Assessment of the Decadal Change of Ecological Environment"
文摘By analyzing current situation of the Caihai Wetland, combining with "3S" technology, theory of ecosystem health, landscape ecology theory, applying the model of Pressure–State–Response, this paper assessed dynamic changes of ecological frangibility of the Caohai Wetland in Guizhou in 1992, 2000 and 2013. The results showed that the wetland ecosystem had sound principal functions, but also witnessed different degrees of degradation. The ratio of basic complete ecosystem landscape area in the Caohai Wetland reduced from 70.56% in 1992 to 66.26% in 2013, and the ratio of destructed landscape area increased from 12.11% in 1992 to 13.38% in 2013.
文摘In this paper, the major objective is to build a global dynamic network model to assess the global health condition .First use the PSR model and Analytic hierarchy process (AHP) to calculate the internal health status of some regions, and then establish a global network model which links each region together to figure out the global health status. Finally, taking the human influence into consideration, the degree of the earth's health can be figured out in a more accurate way.
文摘Along with the rapid development of port building, the negative impacts of port's construction and operation on the coastline ecosystem are also increasingly strong. Therefore, it's urgent to establish a scientific and complete system of port ecological suitability evaluation. This paper pointed out the characteristics of port ecological effects and the principles of selecting evaluation index, and used the "pressure-state-response (PSR)" model to analysis the various pressures on the environment caused by port construction and operation, and the system's response. On this basis, we constructed the port ecological suitability evaluation index. This model used the combination of qualitative and quantitative analytic hierarchy process, to meet the multi-level, multi-objective characteristics of evaluation index system. The evaluation index system and evaluation model can be used to analysis the ecological suitability of port projects comprehensively and have some guiding significance to the port ecological suitability evaluation.
基金This work was supported by the National Natural Science Foundation of China(31770480)the Fundamental Research Funds for the Central Universities(lzujbky-2018-103).
文摘Africa,the second largest continent in the world,has achieved remarkable economic and political results through exploration and positive development.Ecological security comprehensively reflects the health and integrity of an ecosystem,and it is broadly defined as the security state of a complex artificial ecosystem composed of natural,economic and social factors.Ecological security determines the potential for sustainable development in Africa,especially with its rapidly developing economies.However,there is a lack of information on the ecological security state of the continent as a whole.In this study,we constructed an evaluation system based on a pressure-state-response model and evaluated the ecological security state of all 54 African countries.The results showed that,at the national level,the ecological security state of the countries in Africa differed,as did their spatial and temporal variations from 1995 to 2016.In general,African countries showed relatively good ecological security.The years 2007 and 2001 were the worst and best years,respectively,in terms of ecological security during the study period.At the regional level,North Africa andWest Africa had the best and worst ecological security,respectively.