Driven by the concept of agricultural sustainable development,crop planting structure optimization(CPSO)has become an effective measure to reduce regional crop water demand,ensure food security,and protect the environ...Driven by the concept of agricultural sustainable development,crop planting structure optimization(CPSO)has become an effective measure to reduce regional crop water demand,ensure food security,and protect the environment.However,traditional optimization of crop planting structures often ignores the impact on regional food supply–demand relations and interprovincial food trading.Therefore,using a system analysis concept and taking virtual water output as the connecting point,this study proposes a theoretical CPSO framework based on a multi-aspect and full-scale evaluation index system.To this end,a water footprint(WF)simulation module denoted as soil and water assessment tool–water footprint(SWAT-WF)is constructed to simulate the amount and components of regional crop WFs.A multi-objective spatial CPSO model with the objectives of maximizing the regional economic water productivity(EWP),minimizing the blue water dependency(BWFrate),and minimizing the grey water footprint(GWFgrey)is established to achieve an optimal planting layout.Considering various benefits,a fullscale evaluation index system based on region,province,and country scales is constructed.Through an entropy weight technique for order preference by similarity to an ideal solution(TOPSIS)comprehensive evaluation model,the optimal plan is selected from a variety of CPSO plans.The proposed framework is then verified through a case study of the upper–middle reaches of the Heihe River Basin in Gansu province,China.By combining the theory of virtual water trading with system analysis,the optimal planting structure is found.While sacrificing reasonable regional economic benefits,the optimization of the planting structure significantly improves the regional water resource benefits and ecological benefits at different scales.展开更多
Land use structural optimization is an effective approach to realize land sustainable utilization and allocate limited land resource rationally. Grey multiple objectives programming (GMOP) model based on China terrest...Land use structural optimization is an effective approach to realize land sustainable utilization and allocate limited land resource rationally. Grey multiple objectives programming (GMOP) model based on China terrestrial ecosystem service value was constructed and applied to Lilin town. The result shows that GMOP model has more practical applicability and takes ecologic, social and comprehensive benefit into consideration. There are three programs after optimization. Program Ⅰ is comprehensive improvement and constructing ecological economy type, program Ⅱ is gross cultivated land dynamic balance type and program Ⅲ is compromise type. There are still problems in programs Ⅱ and Ⅲ, such as distribution in disorder, land left unused or abandoned. Based on the benefits above, Program Ⅰ>Program Ⅲ> Program Ⅱ. Program Ⅰ is the optimal case. Its comprehensive benefit is 8.43208×107 RMB yuan/a.展开更多
Optimization of land use structure consists of economic and social and ecological optimization.Applying the minds of system engineering and principles of ecology,this paper presents such thoughts:the optimal forest_co...Optimization of land use structure consists of economic and social and ecological optimization.Applying the minds of system engineering and principles of ecology,this paper presents such thoughts:the optimal forest_coverage rate calculated according to the reality of a district is set as main standard of ecological rationality in the district;through considering the value of ecosystem services of the land with GREEN equivalent (mainly cultivated land and grassland)and based on the rule,GREEN equivalent,this paper introduces the area conversion between woodland and cultivated land,also between woodland and grassland;this paper establishes a multi_dimension controlling model of optimization of land use structure.In addition,a multi_objective linear programming model for optimization of land use structure is designed.In the end,this paper tests and verifies this theory of ecological optimization,taking Qionghai city in Hainan Province as an example.展开更多
Trade liberalization requires institutional coordination and openness,and is driven by a multitude of factors.This paper simulates endogenous optimal tariffs under different model structures to uncover the underlying ...Trade liberalization requires institutional coordination and openness,and is driven by a multitude of factors.This paper simulates endogenous optimal tariffs under different model structures to uncover the underlying drivers of trade liberalization.Parametric calibration and simulation methods based on the numeric general equilibrium model are employed to estimate the optimal tariff rates of countries with and without trade retaliation.Then,near-reality assumptions are added into the standard general equilibrium model structure,including the cross-border capital flow,multi-country assumption and trade cost,to simulate decreasing optimal tariff rates.The simulation results suggest that world economic development has increased the economic ties and interdependence among nations,making trade liberalization an endogenous optimal choice.The backlash against globalization in recent years is motivated by short-term factors,but will not persist in the long run since it goes against the law of economic growth and socio-economic development.展开更多
基金financially supported by the National Key Research and Development Program of China(2022YFD1900501)National Natural Science Foundation of China(51861125103)。
文摘Driven by the concept of agricultural sustainable development,crop planting structure optimization(CPSO)has become an effective measure to reduce regional crop water demand,ensure food security,and protect the environment.However,traditional optimization of crop planting structures often ignores the impact on regional food supply–demand relations and interprovincial food trading.Therefore,using a system analysis concept and taking virtual water output as the connecting point,this study proposes a theoretical CPSO framework based on a multi-aspect and full-scale evaluation index system.To this end,a water footprint(WF)simulation module denoted as soil and water assessment tool–water footprint(SWAT-WF)is constructed to simulate the amount and components of regional crop WFs.A multi-objective spatial CPSO model with the objectives of maximizing the regional economic water productivity(EWP),minimizing the blue water dependency(BWFrate),and minimizing the grey water footprint(GWFgrey)is established to achieve an optimal planting layout.Considering various benefits,a fullscale evaluation index system based on region,province,and country scales is constructed.Through an entropy weight technique for order preference by similarity to an ideal solution(TOPSIS)comprehensive evaluation model,the optimal plan is selected from a variety of CPSO plans.The proposed framework is then verified through a case study of the upper–middle reaches of the Heihe River Basin in Gansu province,China.By combining the theory of virtual water trading with system analysis,the optimal planting structure is found.While sacrificing reasonable regional economic benefits,the optimization of the planting structure significantly improves the regional water resource benefits and ecological benefits at different scales.
基金Project(2006BAJ05A14)supported by the National Science and Technology Pillar Program During the 11th Five-year Plan Period,ChinaProject(112400430057)supported by the Soft Science Research Program of Henan Province,ChinaProject(B2010-87)supported by the Foundation for Doctorate Research of Henan Polytechnic University,China
文摘Land use structural optimization is an effective approach to realize land sustainable utilization and allocate limited land resource rationally. Grey multiple objectives programming (GMOP) model based on China terrestrial ecosystem service value was constructed and applied to Lilin town. The result shows that GMOP model has more practical applicability and takes ecologic, social and comprehensive benefit into consideration. There are three programs after optimization. Program Ⅰ is comprehensive improvement and constructing ecological economy type, program Ⅱ is gross cultivated land dynamic balance type and program Ⅲ is compromise type. There are still problems in programs Ⅱ and Ⅲ, such as distribution in disorder, land left unused or abandoned. Based on the benefits above, Program Ⅰ>Program Ⅲ> Program Ⅱ. Program Ⅰ is the optimal case. Its comprehensive benefit is 8.43208×107 RMB yuan/a.
文摘Optimization of land use structure consists of economic and social and ecological optimization.Applying the minds of system engineering and principles of ecology,this paper presents such thoughts:the optimal forest_coverage rate calculated according to the reality of a district is set as main standard of ecological rationality in the district;through considering the value of ecosystem services of the land with GREEN equivalent (mainly cultivated land and grassland)and based on the rule,GREEN equivalent,this paper introduces the area conversion between woodland and cultivated land,also between woodland and grassland;this paper establishes a multi_dimension controlling model of optimization of land use structure.In addition,a multi_objective linear programming model for optimization of land use structure is designed.In the end,this paper tests and verifies this theory of ecological optimization,taking Qionghai city in Hainan Province as an example.
基金the sponsorship of the Post-funded Project of Philosophy and Social Science Research of the Chinese Ministry of Education (19JHQ062)the National Natural Science Foundation of China (NSFC) General Program (71572048) for this paper
文摘Trade liberalization requires institutional coordination and openness,and is driven by a multitude of factors.This paper simulates endogenous optimal tariffs under different model structures to uncover the underlying drivers of trade liberalization.Parametric calibration and simulation methods based on the numeric general equilibrium model are employed to estimate the optimal tariff rates of countries with and without trade retaliation.Then,near-reality assumptions are added into the standard general equilibrium model structure,including the cross-border capital flow,multi-country assumption and trade cost,to simulate decreasing optimal tariff rates.The simulation results suggest that world economic development has increased the economic ties and interdependence among nations,making trade liberalization an endogenous optimal choice.The backlash against globalization in recent years is motivated by short-term factors,but will not persist in the long run since it goes against the law of economic growth and socio-economic development.