We use the secondary relative benefit model based on DEA to evaluate the performance of agricultural financial expenditure in Guizhou Province, which can give due consideration to the production effectiveness determin...We use the secondary relative benefit model based on DEA to evaluate the performance of agricultural financial expenditure in Guizhou Province, which can give due consideration to the production effectiveness determined by objective natural conditions, and management effectiveness of all regions (as decision-making body) in the use of financial fund for supporting agriculture. In general, there is north-south gradient difference in the performance of financial support for agriculture between regions in Guizhou Province. The drought in 2010 has significant impact on the technical efficiency in the whole province; the performance score of each item in Liupanshui City and Southwest Guizhou is very low; the technical efficiency and management efficiency in most regions need to be improved. In order to improve the performance of financial support for agriculture, we need to ensure the scale of input; at the same time, provide appropriate preferential financial policies for agricultural infrastructure, especially the construction of rural water conservancy, development and promotion of agricultural science and technology, and other fields; adopt the way of special check and acceptance of supporting projects to strengthen the use management of the fund for agriculture.展开更多
This paper studies the mechanism of grassland ecosystem's soil and water conservation function on the basis of two years experiment and inspection in Jianou mountain grassland ecosystem experiment station, Fujian ...This paper studies the mechanism of grassland ecosystem's soil and water conservation function on the basis of two years experiment and inspection in Jianou mountain grassland ecosystem experiment station, Fujian province. After anaIysis on the data of soil erosion and runoff coefficient, relations between eroded soil, runoff and slope gradient. we establish soil and water conservation benefit models. According to the mode1s, experiment and inspection results, some proposals have been made to decrease the area of soil erosion in Fujian mountainous areas, e. g., optimizing land use structure in mountainous areas, taking suitable measures for local condition, closing hills for grassland development, accelerating restoration and raising quality of mountain grassland ecosystem, strengthening scientific and technological input, breeding the grass species that are suitable to local physical geographic condition.展开更多
Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in mo...Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in more attention to green manure.Human intervention and policy-oriented behaviors likely have large impacts on promoting green manure planting.However,little information is available regarding on where,at what rates,and in which ways（i.e.,intercropping green manure in orchards or rotating green manure in cropland） to develop green manure and what benefits could be gained by incorporating green manure in fields at the county scale.This paper presents the conversion of land use and its effects at small region extent（CLUE-S） model,which is specifically developed for the simulation of land use changes originally,to predict spatial distribution of green manure in cropland and orchards in 2020 in Pinggu District located in Beijing,China.Four types of land use for planting or not planting green manure were classified and the future land use dynamics（mainly croplands and orchards） were considered in the prediction.Two scenarios were used to predict the spatial distribution of green manure based on data from 2011：The promotion of green manure planting in orchards（scenario 1） and the promotion of simultaneous green manure planting in orchards and croplands（scenario 2）.The predictions were generally accurate based on the receiver operating characteristic（ROC） and Kappa indices,which validated the effectiveness of the CLUE-S model in the prediction.In addition,the spatial distribution of the green manure was acquired,which indicated that green manure mainly located in the orchards of the middle and southern regions of Dahuashan,the western and southern regions of Wangxinzhuang,the middle region of Shandongzhuang,the eastern region of Pinggu and the middle region of Xiagezhuang under scenario 1.Green manure planting under scenario 2 occurred in orchards in the middle region of Wangxinzhuang,and croplands in most regions of Daxingzhuang,southern Pinggu,northern Xiagezhuang and most of Mafang.The spatially explicit results allowed for the assessment of the benefits of these changes based on different economic and ecological indicators.The economic and ecological gains of scenarios 1 and 2 were 175691 900 and143000 300 CNY,respectively,which indicated that the first scenario was more beneficial for promoting the same area of green manure.These results can facilitate policies of promoting green manure and guide the extensive use of green manure in local agricultural production in suitable ways.展开更多
Guangzhou is the capital and largest city（land area：7287 km2）of Guangdong province in South China.The air quality in Guangzhou typically worsens in November due to unfavorable meteorological conditions for pollutan...Guangzhou is the capital and largest city（land area：7287 km2）of Guangdong province in South China.The air quality in Guangzhou typically worsens in November due to unfavorable meteorological conditions for pollutant dispersion.During the Guangzhou Asian Games in November 2010,the Guangzhou government carried out a number of emission control measures that significantly improved the air quality.In this paper,we estimated the acute health outcome changes related to the air quality improvement during the 2010 Guangzhou Asian Games using a next-generation,fully-integrated assessment system for air quality and health benefits.This advanced system generates air quality data by fusing model and monitoring data instead of using monitoring data alone,which provides more reliable results.The air quality estimates retain the spatial distribution of model results while calibrating the value with observations.The results show that the mean PM2.5concentration in November 2010 decreased by 3.5μg/m^3 compared to that in 2009 due to the emission control measures.From the analysis,we estimate that the air quality improvement avoided 106 premature deaths,1869 cases of hospital admission,and 20,026 cases of outpatient visits.The overall cost benefit of the improved air quality is estimated to be 165 million CNY,with the avoided premature death contributing 90%of this figure.The research demonstrates that Ben MAP-CE is capable of assessing the health and cost benefits of air pollution control for sound policy making.展开更多
The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products＇ cost and benefit completely and correctly under the ci...The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products＇ cost and benefit completely and correctly under the circumstance of satisfying enterprise, customer, environment and society. It also puts forth an operable method to estimate social benefit by opportunity cost and establishes a profit maximization-programming model. The model can be applied to justify whether some kinds of green products should be developed and produced.展开更多
Owing to high costs and unnecessary inspections necessitated by the traditional inspection planning for ship structures, the risk-based inspection and repair planning should be investigated for the most cost-effective...Owing to high costs and unnecessary inspections necessitated by the traditional inspection planning for ship structures, the risk-based inspection and repair planning should be investigated for the most cost-effective inspection. This paper aims to propose a cost-benefit assessment model of risk-based inspection and repair planning for ship structures subjected to corrosion deterioration. Then, the benefit-cost ratio is taken to be an index for the selection of the optimal inspection and repair strategy. The planning problem is formulated as an optimization problem where the benefit-cost ratio for the expected lifetime is maximized with a constraint on the minimum acceptalbe reliability index. To account for the effect of corrosion model uncertainty on the cost-benefit assessment, two corrosion models, namgly, Paik＇ s model and Guedes Soares＇ model, are adopted for analysis. A numerical example is presented to illustrate the proposed method. Sensitivity studies are also providet. The results indicate that the proposed method of risk-based cost-benefit analysis can effectively integrate the economy with reliability of the inspection and repair planning. A balance can be achieved between the risk cost and total expected inspection and repair costs with the proposed method, which is very. effective in selecting the optimal inspection and repair strategy. It is pointed out that the corrosion model uncertainty and parametric uncertaintg have a significant impact on the cost-benefit assessment of inspection and repair planning.展开更多
According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding ...According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding in Shandong Province from the perspective of comparing it with that of the entire country and 9 other main pig producing areas. The results show that compared with the national average,the cost-benefit ratio of small scale pig breeding in Shandong Province is lower,while the cost-benefit ratio of medium scale and large scale pig breeding is significantly improved; the cost-benefit ratio of small scale pig breeding in Shandong Province is basically the same as that in 9 other main pig producing areas,while the cost-benefit ratio of medium scale and large scale pig breeding is higher; the output value of main products and the purchase price of piglet are two major bottlenecks restricting the cost-benefit improvement of scale pig breeding in Shandong Province.展开更多
The Hobq Desert is the seventh largest desert in China. Since 1988, the effects of ecological management in Hobq Desert have been obvious and a typical desertification control model developed gradually, which is well ...The Hobq Desert is the seventh largest desert in China. Since 1988, the effects of ecological management in Hobq Desert have been obvious and a typical desertification control model developed gradually, which is well known as the ＂Hobq model＂. It is important to evaluate the comprehensive benefits of the ＂Hobq model＂, but this has not been addressed in previous studies. Thus, we established an index system to comprehensively evaluate the benefits of the ＂Hobq model＂, using an analytic hierarchy process method from 1988 to 2013. The results show the following： ecological benefits of the ＂Hobq model＂ had a positive trend, but with fluctuations during 2008 and 2009; economic benefits increased by 74% and the maximum value occurred in 2013; and social benefits increased steadily, but with fluctuations in 2010 and 2011. The social benefits were higher than ecological and economic benefits in the same period. Trends in overall benefits of the ＂Hobq model＂ were similar to changes in ecological benefits, which increased each year.展开更多
From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have s...From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have some problems unsolved since the model of cost-benefit flow is still centralized and mainly in an administrative way in spite of many efforts made theoretically and practically. It is suggested that a new model based on market-oriented economy from the point of cost-benefit flow with Six Green Projects Management and Policies System consist of complete natural reserve (NR). Management system included environmental nature reserves in addition to biodiversity nature reserve, paid using nature resources, an environmental conservation and construction industry and renewable resource production incentive system that turn the direct administration and operation to management and services. The detail figure of the new model of cost-benefit flow is provided and the main points related are discussed in this paper.展开更多
Based on the threshold panel data model,this paper analyzed the nonlinear relationship between chemical fertilizer input and grain output. At the provincial level,from the perspective of average and marginal net benef...Based on the threshold panel data model,this paper analyzed the nonlinear relationship between chemical fertilizer input and grain output. At the provincial level,from the perspective of average and marginal net benefits,it compared the effects of chemical fertilizer input on farmers' income. It reached the conclusion that the chemical fertilizer input efficiency has deviated from the optimal level. Thus,only by increasing the marginal productivity of chemical fertilizers,may it be able to increase farmers' income.展开更多
Fine particulate matter (PM<sub>2.5</sub>) mainly originates from combustion emissions on-road transportation. Exposure to PM<sub>2.5</sub> could be considered one of the primary causes of dise...Fine particulate matter (PM<sub>2.5</sub>) mainly originates from combustion emissions on-road transportation. Exposure to PM<sub>2.5</sub> could be considered one of the primary causes of diseases such as heart attack, stroke, lung cancer, and chronic respiratory, which made it one of the most important co-benefits when evaluating the impact of GHG mitigation measures. This study quantifies the co-benefit of Ha Noi’s modal shift from private to public means of transport, which are reduced air pollution and extended life expectancy, combining AERMOD model and benefit transfer method. Analytical results show that shifting from motorbike to electric train could be the most beneficial option in term of health co-benefit, compared to the usage of standard buses and BRTs.展开更多
抽水蓄能作为电力系统中最为成熟的新能源储能技术,凭借其能调节电网负荷、平衡电力波动及提升系统稳定性的独特优势,已成为实现中国“双碳”目标的重要路径之一。因此,对抽水蓄能电站综合效益进行科学评估,是项目决策及政策制定中至关...抽水蓄能作为电力系统中最为成熟的新能源储能技术,凭借其能调节电网负荷、平衡电力波动及提升系统稳定性的独特优势,已成为实现中国“双碳”目标的重要路径之一。因此,对抽水蓄能电站综合效益进行科学评估,是项目决策及政策制定中至关重要的一环。为此,本文提出一种基于博弈论组合赋权‒云模型的综合效益评价模型。首先,运用社会网络分析法(SNA)筛选关键评价指标,构建包含财务评价、国民经济评价、技术效益、动态效益、静态效益、电网效益、综合可持续性效益和社会效益8个1级指标及其下属30个2级指标的评价指标体系。其次,采用序关系分析(G1)法和CRITIC(criteria importance through intercriteria correlation)法相结合的方式,对各评价指标进行主观与客观权重赋值。通过引入博弈论组合赋权方法,进一步优化各指标的权重分配。最终,基于云模型构建综合效益评价模型。利用博弈论组合赋权‒云模型对紫云山抽水蓄能电站进行实例分析,结果表明,该电站的综合效益评估等级为“好”,与实际情况相符,充分验证了所构建模型的有效性与准确性。该研究不仅为抽水蓄能电站的综合效益评估提供了科学的评估框架,并为类似项目的决策和实施提供了理论支持和实践依据。展开更多
国土空间功能分区是构建可持续开发保护格局、提升资源利用效率的重要途径,但传统方法多侧重功能相似性识别,缺乏对生态、农业、城镇等多类管理目标及成本效益的系统统筹。该研究引入系统保护理念,构建“目标-成本-效益”协同优化的国...国土空间功能分区是构建可持续开发保护格局、提升资源利用效率的重要途径,但传统方法多侧重功能相似性识别,缺乏对生态、农业、城镇等多类管理目标及成本效益的系统统筹。该研究引入系统保护理念,构建“目标-成本-效益”协同优化的国土空间功能分区理论框架,综合运用适宜性评价、景观格局指数分析和分区优化模型(Marxan with Zones),形成由主导功能区与功能混合区构成的分区方法,并在江阴市开展实证研究。结果表明:1)优化分区方案显著提升了自然生态系统的代表性与保护效益,乔木林地、灌木林地等关键生态系统的保护比例提升至30%以上。2)在满足生态保护目标的前提下,农业与城镇功能空间得到适度拓展,基本农田和城镇开发规模较现状有所增加,单位面积成本增幅保持在10%以内,体现出较强的综合效益。3)优化方案在空间结构上呈现较高的集聚性与协调性,集约化农区聚集度由71.21提升至88.5,通过功能混合区在严格保护区与城镇建设区之间构建了有效的过渡带,缓解了潜在的空间利用冲突。研究可为高冲突区域优化国土空间格局和完善主体功能区制度提供方法与实践参考。展开更多
基金Key Chongqing Municipal Humanities and Social Sciences Research Base Project in Southwest University(SWU0810026)the Fundamental Research Funds for the Central Universities(SWU1209457 and SWU0909510)+5 种基金National Soft Science Fund(2007GXS3D094)Youth Fund Project of Southwest Normal University(SWU07106)Chongqing Soft Science Project(CSTC,2009CE9016)2012 Shizhu Base Science and Technology Innovation Special Fund Projects(sz201208)National Social Science Fund Project(12ASH00412AGL008)
文摘We use the secondary relative benefit model based on DEA to evaluate the performance of agricultural financial expenditure in Guizhou Province, which can give due consideration to the production effectiveness determined by objective natural conditions, and management effectiveness of all regions (as decision-making body) in the use of financial fund for supporting agriculture. In general, there is north-south gradient difference in the performance of financial support for agriculture between regions in Guizhou Province. The drought in 2010 has significant impact on the technical efficiency in the whole province; the performance score of each item in Liupanshui City and Southwest Guizhou is very low; the technical efficiency and management efficiency in most regions need to be improved. In order to improve the performance of financial support for agriculture, we need to ensure the scale of input; at the same time, provide appropriate preferential financial policies for agricultural infrastructure, especially the construction of rural water conservancy, development and promotion of agricultural science and technology, and other fields; adopt the way of special check and acceptance of supporting projects to strengthen the use management of the fund for agriculture.
基金The project is supported by Henan Province Natural Science Foundation (004070900)HenanProvince Scientific an
文摘This paper studies the mechanism of grassland ecosystem's soil and water conservation function on the basis of two years experiment and inspection in Jianou mountain grassland ecosystem experiment station, Fujian province. After anaIysis on the data of soil erosion and runoff coefficient, relations between eroded soil, runoff and slope gradient. we establish soil and water conservation benefit models. According to the mode1s, experiment and inspection results, some proposals have been made to decrease the area of soil erosion in Fujian mountainous areas, e. g., optimizing land use structure in mountainous areas, taking suitable measures for local condition, closing hills for grassland development, accelerating restoration and raising quality of mountain grassland ecosystem, strengthening scientific and technological input, breeding the grass species that are suitable to local physical geographic condition.
基金supported by the Special Fund for Agroscientific Research in the Public Interest,China(20110300501-01)the Special Fund for First-Class University (4572-18101510)
文摘Green manure use in China has declined rapidly since the 1980 s with the extensive use of chemical fertilizers.The deterioration of field environments and the demand for green agricultural products have resulted in more attention to green manure.Human intervention and policy-oriented behaviors likely have large impacts on promoting green manure planting.However,little information is available regarding on where,at what rates,and in which ways（i.e.,intercropping green manure in orchards or rotating green manure in cropland） to develop green manure and what benefits could be gained by incorporating green manure in fields at the county scale.This paper presents the conversion of land use and its effects at small region extent（CLUE-S） model,which is specifically developed for the simulation of land use changes originally,to predict spatial distribution of green manure in cropland and orchards in 2020 in Pinggu District located in Beijing,China.Four types of land use for planting or not planting green manure were classified and the future land use dynamics（mainly croplands and orchards） were considered in the prediction.Two scenarios were used to predict the spatial distribution of green manure based on data from 2011：The promotion of green manure planting in orchards（scenario 1） and the promotion of simultaneous green manure planting in orchards and croplands（scenario 2）.The predictions were generally accurate based on the receiver operating characteristic（ROC） and Kappa indices,which validated the effectiveness of the CLUE-S model in the prediction.In addition,the spatial distribution of the green manure was acquired,which indicated that green manure mainly located in the orchards of the middle and southern regions of Dahuashan,the western and southern regions of Wangxinzhuang,the middle region of Shandongzhuang,the eastern region of Pinggu and the middle region of Xiagezhuang under scenario 1.Green manure planting under scenario 2 occurred in orchards in the middle region of Wangxinzhuang,and croplands in most regions of Daxingzhuang,southern Pinggu,northern Xiagezhuang and most of Mafang.The spatially explicit results allowed for the assessment of the benefits of these changes based on different economic and ecological indicators.The economic and ecological gains of scenarios 1 and 2 were 175691 900 and143000 300 CNY,respectively,which indicated that the first scenario was more beneficial for promoting the same area of green manure.These results can facilitate policies of promoting green manure and guide the extensive use of green manure in local agricultural production in suitable ways.
基金provided by the US Environmental Protection Agency(No.5-312-0212979-51786L)the Guangzhou EnvironmentalProtection Bureau(No.x2hj B2150020)+3 种基金the project of an integrated modeling and filed observational verification on the deposition of typical industrial point-source mercury emissions in the Pearl River Deltsupported by the funding of the Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control(No.2011A060901011)the project of Atmospheric Haze Collaboration Control Technology Design from the Chinese Academy of Sciences(No.XDB05030400)the National Environmental Protection Public Welfare Industry Targeted Research Foundation of China(No.201409019)
文摘Guangzhou is the capital and largest city（land area：7287 km2）of Guangdong province in South China.The air quality in Guangzhou typically worsens in November due to unfavorable meteorological conditions for pollutant dispersion.During the Guangzhou Asian Games in November 2010,the Guangzhou government carried out a number of emission control measures that significantly improved the air quality.In this paper,we estimated the acute health outcome changes related to the air quality improvement during the 2010 Guangzhou Asian Games using a next-generation,fully-integrated assessment system for air quality and health benefits.This advanced system generates air quality data by fusing model and monitoring data instead of using monitoring data alone,which provides more reliable results.The air quality estimates retain the spatial distribution of model results while calibrating the value with observations.The results show that the mean PM2.5concentration in November 2010 decreased by 3.5μg/m^3 compared to that in 2009 due to the emission control measures.From the analysis,we estimate that the air quality improvement avoided 106 premature deaths,1869 cases of hospital admission,and 20,026 cases of outpatient visits.The overall cost benefit of the improved air quality is estimated to be 165 million CNY,with the avoided premature death contributing 90%of this figure.The research demonstrates that Ben MAP-CE is capable of assessing the health and cost benefits of air pollution control for sound policy making.
基金This paper is supported by National Nature Science Foundation of China （No.70472034）.
文摘The paper builds up a cost-benefit measuring model of green products in manufacturing industry throughout its full life cycle, which can quantify green products＇ cost and benefit completely and correctly under the circumstance of satisfying enterprise, customer, environment and society. It also puts forth an operable method to estimate social benefit by opportunity cost and establishes a profit maximization-programming model. The model can be applied to justify whether some kinds of green products should be developed and produced.
文摘Owing to high costs and unnecessary inspections necessitated by the traditional inspection planning for ship structures, the risk-based inspection and repair planning should be investigated for the most cost-effective inspection. This paper aims to propose a cost-benefit assessment model of risk-based inspection and repair planning for ship structures subjected to corrosion deterioration. Then, the benefit-cost ratio is taken to be an index for the selection of the optimal inspection and repair strategy. The planning problem is formulated as an optimization problem where the benefit-cost ratio for the expected lifetime is maximized with a constraint on the minimum acceptalbe reliability index. To account for the effect of corrosion model uncertainty on the cost-benefit assessment, two corrosion models, namgly, Paik＇ s model and Guedes Soares＇ model, are adopted for analysis. A numerical example is presented to illustrate the proposed method. Sensitivity studies are also providet. The results indicate that the proposed method of risk-based cost-benefit analysis can effectively integrate the economy with reliability of the inspection and repair planning. A balance can be achieved between the risk cost and total expected inspection and repair costs with the proposed method, which is very. effective in selecting the optimal inspection and repair strategy. It is pointed out that the corrosion model uncertainty and parametric uncertaintg have a significant impact on the cost-benefit assessment of inspection and repair planning.
基金Supported by Pig Industry Innovation Team Building Program of Modern Agricultural Industrial Technology System in Shandong Province(SDAIT-06-011-10)"Issues concerning Agriculture,Farmers and Countryside"Soft Science Base Project in Shandong Province
文摘According to the relevant statistical data in National Agricultural cost-benefit Data Compilation(2001- 2013),we use the modified entropy weight- TOPSIS model to research the cost-benefit status of scale pig breeding in Shandong Province from the perspective of comparing it with that of the entire country and 9 other main pig producing areas. The results show that compared with the national average,the cost-benefit ratio of small scale pig breeding in Shandong Province is lower,while the cost-benefit ratio of medium scale and large scale pig breeding is significantly improved; the cost-benefit ratio of small scale pig breeding in Shandong Province is basically the same as that in 9 other main pig producing areas,while the cost-benefit ratio of medium scale and large scale pig breeding is higher; the output value of main products and the purchase price of piglet are two major bottlenecks restricting the cost-benefit improvement of scale pig breeding in Shandong Province.
基金supported by the National Key R&D Program of China(Grant No.2016YFC0500909)the National Science and Technology Support Program of China(Grant No.2015BAC06B01)
文摘The Hobq Desert is the seventh largest desert in China. Since 1988, the effects of ecological management in Hobq Desert have been obvious and a typical desertification control model developed gradually, which is well known as the ＂Hobq model＂. It is important to evaluate the comprehensive benefits of the ＂Hobq model＂, but this has not been addressed in previous studies. Thus, we established an index system to comprehensively evaluate the benefits of the ＂Hobq model＂, using an analytic hierarchy process method from 1988 to 2013. The results show the following： ecological benefits of the ＂Hobq model＂ had a positive trend, but with fluctuations during 2008 and 2009; economic benefits increased by 74% and the maximum value occurred in 2013; and social benefits increased steadily, but with fluctuations in 2010 and 2011. The social benefits were higher than ecological and economic benefits in the same period. Trends in overall benefits of the ＂Hobq model＂ were similar to changes in ecological benefits, which increased each year.
文摘From the point of cost-benefit flow and with the Six Green Projects in China as the case and background, it is criticized that the current natural resource and environmental management and the policies in China have some problems unsolved since the model of cost-benefit flow is still centralized and mainly in an administrative way in spite of many efforts made theoretically and practically. It is suggested that a new model based on market-oriented economy from the point of cost-benefit flow with Six Green Projects Management and Policies System consist of complete natural reserve (NR). Management system included environmental nature reserves in addition to biodiversity nature reserve, paid using nature resources, an environmental conservation and construction industry and renewable resource production incentive system that turn the direct administration and operation to management and services. The detail figure of the new model of cost-benefit flow is provided and the main points related are discussed in this paper.
文摘Based on the threshold panel data model,this paper analyzed the nonlinear relationship between chemical fertilizer input and grain output. At the provincial level,from the perspective of average and marginal net benefits,it compared the effects of chemical fertilizer input on farmers' income. It reached the conclusion that the chemical fertilizer input efficiency has deviated from the optimal level. Thus,only by increasing the marginal productivity of chemical fertilizers,may it be able to increase farmers' income.
文摘Fine particulate matter (PM<sub>2.5</sub>) mainly originates from combustion emissions on-road transportation. Exposure to PM<sub>2.5</sub> could be considered one of the primary causes of diseases such as heart attack, stroke, lung cancer, and chronic respiratory, which made it one of the most important co-benefits when evaluating the impact of GHG mitigation measures. This study quantifies the co-benefit of Ha Noi’s modal shift from private to public means of transport, which are reduced air pollution and extended life expectancy, combining AERMOD model and benefit transfer method. Analytical results show that shifting from motorbike to electric train could be the most beneficial option in term of health co-benefit, compared to the usage of standard buses and BRTs.
文摘抽水蓄能作为电力系统中最为成熟的新能源储能技术,凭借其能调节电网负荷、平衡电力波动及提升系统稳定性的独特优势,已成为实现中国“双碳”目标的重要路径之一。因此,对抽水蓄能电站综合效益进行科学评估,是项目决策及政策制定中至关重要的一环。为此,本文提出一种基于博弈论组合赋权‒云模型的综合效益评价模型。首先,运用社会网络分析法(SNA)筛选关键评价指标,构建包含财务评价、国民经济评价、技术效益、动态效益、静态效益、电网效益、综合可持续性效益和社会效益8个1级指标及其下属30个2级指标的评价指标体系。其次,采用序关系分析(G1)法和CRITIC(criteria importance through intercriteria correlation)法相结合的方式,对各评价指标进行主观与客观权重赋值。通过引入博弈论组合赋权方法,进一步优化各指标的权重分配。最终,基于云模型构建综合效益评价模型。利用博弈论组合赋权‒云模型对紫云山抽水蓄能电站进行实例分析,结果表明,该电站的综合效益评估等级为“好”,与实际情况相符,充分验证了所构建模型的有效性与准确性。该研究不仅为抽水蓄能电站的综合效益评估提供了科学的评估框架,并为类似项目的决策和实施提供了理论支持和实践依据。
文摘国土空间功能分区是构建可持续开发保护格局、提升资源利用效率的重要途径,但传统方法多侧重功能相似性识别,缺乏对生态、农业、城镇等多类管理目标及成本效益的系统统筹。该研究引入系统保护理念,构建“目标-成本-效益”协同优化的国土空间功能分区理论框架,综合运用适宜性评价、景观格局指数分析和分区优化模型(Marxan with Zones),形成由主导功能区与功能混合区构成的分区方法,并在江阴市开展实证研究。结果表明:1)优化分区方案显著提升了自然生态系统的代表性与保护效益,乔木林地、灌木林地等关键生态系统的保护比例提升至30%以上。2)在满足生态保护目标的前提下,农业与城镇功能空间得到适度拓展,基本农田和城镇开发规模较现状有所增加,单位面积成本增幅保持在10%以内,体现出较强的综合效益。3)优化方案在空间结构上呈现较高的集聚性与协调性,集约化农区聚集度由71.21提升至88.5,通过功能混合区在严格保护区与城镇建设区之间构建了有效的过渡带,缓解了潜在的空间利用冲突。研究可为高冲突区域优化国土空间格局和完善主体功能区制度提供方法与实践参考。
