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21.
徐州市生态经济系统的能值分析   总被引:3,自引:0,他引:3  
本文应用能值理论.对徐州地区生态经济系统进行了分析.主要涉及能值投入率、能值使用强度(能值密度)、人均能值使用量、人口承载力、电力能值使用量比、能值一货币比、环境负荷率、净能值产出率、可持续发展指数等9个指标及其发展趋势,并与其他国家和地区的有关指标进行了比较研究。结论表明,徐州市是资源输出型的生态经济区域,经济发展仍处于欠发达阶段.还有较大的经济发展潜力。  相似文献   
22.
Land conservation technologies used by farmers are known to play an important role in improving farm incomes and household welfare in the long run. For this reason substantial investments have been made in research to improve agricultural technologies in various parts of the world, from the development of new crop varieties to new practices of land management. This paper explores the impact of land rights among other factors on adoption of soil and water conservation practices. The study further tests for Boserup's hypothesis (correlation between population density, land conservation and property rights) using panel survey data collected from farming households. The key findings of the paper are that property right regimes and population density affect both the decision to conserve land as well as the type of conservation practices used by farmers. The results further suggest a positive correlation between land tenure security and population density, thus supporting Boserup's hypothesis. The findings call for pursuit of both short-term and long-term policy measures that offer incentives for land conservation through government initiatives and participation of local communities.  相似文献   
23.
Use of biofuels diminishes fossil fuelcombustion thereby also reducing net greenhousegas emissions. However, subsidies are neededto make agricultural biofuel productioneconomically feasible. To explore the economicpotential of biofuels in a greenhouse gasmitigation market, we incorporate data onproduction and biofuel processing for thedesignated energy crops switchgrass, hybridpoplar, and willow in an U.S. AgriculturalSector Model along with data on traditionalcrop-livestock production and processing, andafforestation of cropland. Net emissioncoefficients on all included agriculturalpractices are estimated through crop growthsimulation models or taken from the literature. Potential emission mitigation policies ormarkets are simulated via hypothetical carbonprices. At each carbon price level, theAgricultural Sector Model computes the newmarket equilibrium, revealing agriculturalcommodity prices, regionally specificproduction, input use, and welfare levels,environmental impacts, and adoption ofalternative management practices such asbiofuel production. Results indicate no rolefor biofuels below carbon prices of $40 perton of carbon equivalent. At these incentivelevels, emission reductions via reduced soiltillage and afforestation are more costefficient. For carbon prices above $70,biofuels dominate all other agriculturalmitigation strategies.  相似文献   
24.
基于能值分析的江苏生态经济系统发展态势及持续发展对策   总被引:21,自引:1,他引:21  
能值分析方法可同时定量研究生态经济系统中环境资源与经济活动的真实价值,因而对合理评估区域经济发展水平、制订正确的社会经济发展对策具有十分重要的意义。文章运用能值分析方法对江苏生态经济系统的发展现状及近20年来的发展态势进行了定量分析,并提出实现江苏生态经济系统持续发展的对策建议。  相似文献   
25.
基于循环经济理论的建筑节能研究   总被引:2,自引:0,他引:2  
赵晨钢 《基建优化》2007,28(3):52-54
建筑节能是贯彻国家可持续发展战略的重要组成部分,循环经济理论将为我国建筑节能政策提供良好的思路.文章在分析循环经济理论基本内涵的基础上,分析循环经济理论对我国建筑节能工作的指导意义,并结合当前我国建筑节能现状及其存在的问题,根据“十一五“规划目标,提出新时期我国建筑节能对策.  相似文献   
26.
文章对多年来在民用建筑循环冷却水系统设计、运行中碰到的一些问题,提出在设计时应注意的事项及所需要采取的措施。  相似文献   
27.
油价上涨给世界经济带来很大影响,引发了经济危机、加重了西方国家的财政负担和生产成本、加大了非产油国家的进口成本。高油价也给航空、速递等一些运输行业造成沉重负担,油价上涨的最终承担者是消费者。油价不断上涨促使各国调整能源结构,高油价给石油输出国带来丰厚收益的同时也带来一些负面影响,如腐败、暴力冲突、战争等。油价上涨要求中国大幅提高能源利用率,采用多元化能源战略,尽快建立国家石油战略储备,加强能源领域国际合作。  相似文献   
28.
This paper proposes a spatial structural decomposition analysis to measure the effects of the changes in intra- and inter-country linkages on the embodied energy demand in the concerned country. For the empirical analysis, we have used the China- Japan inter-country input–output tables for 1985 and 1990, expressed in constant prices of 1990. The empirical results reveal that (1) at least for the period between 1985 and 1990, the effects of the non-competitive input structural changes in China on the primary energy requirements of Japan were negligible, and (2) the contribution of the Japanese final demand shifts on the total change in Chinese primary energy demand was 40 times larger than that of the Chinese final demand shifts on the primary energy requirements of Japan. The Japanese policy makers should concentrate on the energy impacts of the changes in the domestic production structure rather than the changes in the Chinese production structure.  相似文献   
29.
试论研究环境问题的三种理论框架   总被引:1,自引:0,他引:1  
本文认为,对环境问题的理论研究大致分三种脉络:外部性与社会福利、公地的悲剧与环境产权、物质平衡模型与可持续发展规划。依据这三种理论框架,解决环境问题的对策措施需要同时从市场机制建设、人类社会发展目标确定与技术途径三个方面展开。  相似文献   
30.
Integrating ecosystem services into conservation assessments: A review   总被引:8,自引:0,他引:8  
A call has been made for conservation planners to include ecosystem services into their assessments of conservation priority areas. The need to develop an integrated approach to meeting different conservation objectives and a shift in focus towards human wellbeing are some of the motivations behind this call. There is currently no widely accepted approach to planning for ecosystem services. This study contributes towards the development of this approach through a review of conservation assessments and the extent to which they include ecosystem services. Of the 476 conservation assessments identified by a set of search terms on the Web of Science, 100 were randomly selected for this review. Of these only seven had included ecosystem services, while another 13 had referred to ecosystem services as a rationale for conservation without including them in the assessment. The majority of assessments were based on biodiversity pattern data while 19 used data on ecological processes. A total of 11 of these 19 assessments used processes, which could be linked to services. Ecosystem services have witnessed an increase in attention received in conservation assessments since the year 2000, however trends were not apparent beyond this date. In order to assess which types of ecosystem services and how they have been accounted for in conservation assessments, we extended our review to include an additional nine conservation assessments which included ecosystem services. The majority included cultural ecosystem services, followed by regulatory, provisioning and supporting services respectively. We conclude with an analysis of the constraints and opportunities for the integration of ecosystem services into conservation assessments and highlight the urgent need for an appropriate framework for planning for ecosystem services.  相似文献   
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