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871.
将交易成本分析引入沙漠化地区生态建设政策分析过程, 确定交易成本由搜寻信息成本、签订合约成本、建设及营运成本、监督对方是否违约成本、违约后寻求赔偿成本共5部分构成. 每个部分根据研究区域生态政策实施的关键节点进行指标分解, 设计政策交易成本分析的21个指标. 为了将不同生态政策之间的绩效进行对比, 构造了交易成本结构指数, 它由内生交易成本占总交易成本的比重、农户投入占生态建设项目生产成本的比重、交易成本占生态建设项目交易成本与生产成本之和的比重共3个指标构成. 根据在宁夏盐池县的调研数据, 测算退耕还林政策和天然林保护政策的交易成本分别为640.87元·hm-2·a-1和41.49元·hm-2·a-1, 交易成本结构指数值分别为0.1242和0.2292, 实施效果分别是很好和较好;"三北"防护林政策的交易成本为806.08元·hm-2·a-1, 交易成本结构指数值为0.4149, 实施效果一般;草地禁牧政策的交易成本为530.45元·hm-2·a-1, 交易成本结构指数值为0.8575, 实施效果很差. 生态政策的交易成本及其结构分析, 将为不同生态建设政策的比较和绩效评价提供一个新的角度, 具有重要意义. 相似文献
872.
利用非市场价值评估的方法——条件价值法,通过估算公众对CO2减排政策的支付意愿,评估中国减缓气候变化政策的价值。利用从北京、上海、山东、福建4个省市收集的1653份有效调查问卷,建立支付意愿模型。结果表明,绝大部分参与者对CO2减排政策持明显的支持态度,平均每人每年愿意支付201.86元人民币以支持减排行动。其中,北京地区的参与者CO2减排的支付意愿最高,其次为福建和山东,上海参与者的支付意愿最低。模型显示,年轻、男性和中共党员参与者愿意支付较高的额度支持CO2减排行动,收入水平高、对目前的生活状况满意、对气候变化问题有较好理解的参与者支付意愿也高。这一研究的政策启示是:中国低碳发展需要将公众对气候政策的支持意愿转化为切实的低碳行动,在设计碳税等减排机制时还要关注不同地区和收入群体在支付意愿和能力上的差异。 相似文献
873.
Acceptance limits of the structural response of walls for low‐rise concrete housing were developed. Proposed values are applicable within a performance‐based seismic design framework. Acceptance limits are based on performance indicators of structural response–allowable story drift ratios, width of residual cracks and residual damage index, and expected damage of walls. Cracking limits were defined from parameters obtained at the unloading stage of walls (i.e., residual cracking stage). The residual cracking stage may be used for structural damage evaluation and cost estimation of structural rehabilitation after an earthquake has occurred. The performance indicators proposed herein were derived from test observations and measured response of 39 RC walls' specimens during shaking table and quasistatic testing, as well as from limiting values and results of previous studies. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
874.
875.
While the global network of marine protected areas (MPAs) has recently been evaluated in the light of bio-geographic targets, there has been no attempt to evaluate the relative conservation efforts made by the different nations with regards to their level of socio-economic development. Using information mostly gathered from the world database on protected areas (WDPA), this paper gives a comparative assessment of MPA progress in countries from different economic categories, ranging from advanced economies to least developed countries (LDCs). Potentially explanatory socio-economic and environmental factors, such as fishing activity and existence of vulnerable marine ecosystems, for variability between nations in the level of MPA implementation are also explored. Existing MPA databases demonstrate a clear gap between developed and developing nations in MPA establishment, with advanced economies accounting for two thirds of the global MPA network. Patterns of MPA use, however, remain extremely heterogeneous between countries within each development group. International agreements on marine conservation, above and beyond the influence of country socio-economic and environmental profiles, are identified as a stimulating factor to MPA implementation. The level dependence on marine resource extraction appears to impede MPA implementation, though the relationship is not statistically significant due to large heterogeneity among countries. Leading developed nations increasingly use MPAs to designate integrated and adaptive management areas, and implementation of large “no-take” reserves in relatively-pristine overseas areas continues to accelerate. These analyses highlight certain limitations regarding our ability to assess the true conservation effectiveness of the existing global MPA network and the need for improved indicators of MPA restrictions and management efforts. 相似文献
876.
This paper presents how environmental concerns emanating outside the Common Fisheries Policy (CFP) are increasingly setting the stage for EU fisheries management. This is illustrated via what is termed the exogenous entrance of environmental concerns through the implementation of directives in EU policy. More endogenous entrance of environmental concerns occurs via stakeholder participation in Regional Advisory Councils (RACs) as well as market mechanisms, such as ecolabelling and traceability. This study discusses how these latter channels of environmental concern may have become a more potent and efficient way of reaching environmental goals, outside of the primacy of the CFP. 相似文献
877.
The Road to Rio+20 is the journey of countries in the world pursuing the sustainable development.As the first country to release the national Agenda 21,China’s experience and lessons are of great significance for both China itself and other countries.The paper reviews the progress made and problems remained in pursuing the sustainable development in China with regard to policy formulation,institutional arrangements,planning and management.In the past five years,the mandatory targets-driven approach,which focused on energy efficiency and key pollutants reduction,played a very important role and made China comprehensive outcomes for sustainability.In order to achieve the targets,China adopted an integrated policy package including legal,administrative,economic and technology instruments.During the 12th Five-Year Plan period(2011-2015),China will continue and strengthen the approach above and mainstream the transformation of economic development pattern through realizing the idea of green and low-carbon development.By summarizing policy trends in the world,the paper points out two directions,i.e.,integration approach and taking prioritized and concrete actions for a sustainable future beyond 2012.The paper also presents policy approaches and recommendations for sustainable development in the next 10 years in China. 相似文献
878.
世界能源地理研究进展及学科发展展望 总被引:6,自引:2,他引:4
面向国家重大战略需求,应对日益严峻的国际能源环境,开展世界能源地理研究是经济地理学家的重要使命.但从目前的研究来看,缺乏系统的地理学视角,研究主要集中在政治学、外交学、经济学等领域.相关学科涉及能源地理学的研究主要集中在3 个方面:① 世界能源地缘政治格局研究;② 世界能源地缘政治格局中的中国能源安全研究,包括能源供给、运输、储备等;③ 中国能源合作与能源外交研究.展望未来,应从3 个方面加强世界能源地理的研究:① 建立系统的研究框架,全面把握世界能源状态、格局及其演变规律;② 建立世界能源的动态数据库,加强模拟分析与可视化表达能力;③ 加强研究平台建设,培养研究队伍. 相似文献
879.
黄丹丽 《广东海洋大学学报》2013,(5):27-30
随着广东省海洋经济发展,其无居民海岛利用的深度和广度进一步加大,相关政策的作用开始凸显,但经济效益型无居民海岛无人问津、生态保护型与生态修复型无居民海岛遭严重破坏、海洋权益型无居民海岛亟需保护等问题严重。针对当前现状,政府今后的政策趋势应主要集中在三方面:一是明确产权管理,二是加强执法力度,三是实行分类管理。在制定无居民海岛发展政策时,要结合地方特点并不断探讨、制定与国家层面相配套的地方法规和政策措施,从而推动无居民海岛的可持续发展。 相似文献
880.
从信号传递角度出发,研究土地出让事件冲击带来的房价变化在时间和空间上的扩散效应。利用杭州2006年1月-2010年3月177宗住宅用地成交数据和251个新建商品住宅楼盘交易数据,借助GIS相关软件展开实证研究,结果发现:①土地出让价格信号引起房价的变化,对房价的影响具有“不对称性”;②房价变化以出让地块为中心往外扩散,呈现“波纹效应”;③房价变化具有“持续性”,土地出让价格信号对房价的影响持续四个月,影响范围达3 km以上;④房价波动强度随时间推移和空间延伸不断渐弱。对此,政府应尽量保持地价平稳,规避地价信号所产生的市场波动风险。 相似文献