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11.
Quantifying the monetary value of ecosystem services (ES) provided by coastal and marine resources can help policy makers assess the trade-offs and synergies inherent in ecosystem-based management of marine and coastal environments, thus increasing the social efficiency of decision-making processes. As shown by the valuation literature, the number of coastal and marine management settings where valuation researchers have attempted to make a contribution is rising fast. However, this rise in research activity has not been matched by the increase in the use of economic valuation (EV) in the actual management of coastal and marine resources. This raises an interesting question: is EV responding to the needs of policy makers? This paper provides a comprehensive overview of the knowledge base regarding the economic values for coastal and marine ecosystems. It then discusses how to improve the uptake of ES valuation research by focussing on two core issues which are thought to be essential for more effective communication with the policy community.  相似文献   
12.
杨振山  蔡建明 《地理研究》2007,26(2):363-372
都市农业是城市化进程中崭新的农业形态,但缺乏对其组织形式和生产方式的实证研究。本文基于对互润(国际)食品集团的调查实例,详细分析了都市农业加工型企业的成长机理,指出制度平台、政府行为和社区沟通是企业发展的外层机理,是企业平稳运行的基础;生产经营活动及其不断的扩张构成了企业发展的内层机理;创新和企业管理及市场的内、外部控制所形成的内核机理是企业发展的核心动力。据此,文章总结了都市农业加工型企业的发展模式,并就都市农业加工型企业如何发展提出了建议。  相似文献   
13.
气象预报服务效益评估方法研究——以暴雨预报服务为例   总被引:6,自引:3,他引:3  
暴雨是江苏的重要气象灾害之一,为了对暴雨预报气象服务效益作出恰当的评估,我们设计了预报准确率V、预报服务覆盖率P、预报服务时效率N、可能预防能力Z等四个指标,给出了定量评估暴雨预报气象服务效益的数学模型,并且用实例说明了该模型的实用性和可操作性.预报服务覆盖率、预报服务时效和预报准确率与服务效益成正比,各个因子都会很大程度上影响服务效益值.预防能力越强,气象服务的效益越大,这也说明了气象预报只是一种信息,信息价值的体现还在于应用信息群体的决策和防御能力.  相似文献   
14.
黄淮海平原农业综合开发的效益和粮食增产潜力   总被引:2,自引:0,他引:2  
吴凯  谢明 《地理研究》1996,15(3):70-76
黄淮海平原经过1988-1993年农业综合开发,取得了明显的经济、生态和社会效益。改造中低产田409万ha,开发区粮食年平均增长率达4.0%,其增产量占全区增产总量的42.5%,农业开发的贡献几乎与传统农业的贡献相等。预测1995-2000年,即使是农业综合开发的规模与前六年相同,但是,由于水利工程效益更充分地发挥和农业的科技含量持续增长,开发区粮食完全可能增产达90亿kg.  相似文献   
15.
Conventional sectoral management and piecemeal governance are considered less and less appropriate in pursuit of sustainable development. Ecosystem based marine spatial management (EB-MSM) is an approach that recognizes the full array of interactions within an ecosystem, including human uses, rather than considering single issues, species, or ecosystem services in isolation. Marine spatial planning and ocean zoning are emerging concepts that can support EB-MSM. EB-MSM is driven by high-level goals that managers aim to achieve through the implementation of measures. High-level goals and objectives need to be translated into more operational objectives before specific targets, limits and measures can be elaborated.Monitoring, evaluation and adaptation are necessary to ensure that marine management measures are both effective and efficient. Solid monitoring frameworks are the foundation of adaptive management, as they provide the necessary information to evaluate performance and the effectiveness of management actions. Marine protected areas (MPAs) - possibly set up in networks - constitute a key component in EB-MSM policies and practises and have been applied as a cornerstone in conservation of marine biodiversity, management of fish populations, development of coastal tourism, etc. Moreover, MPA experiences have provided methods and concepts (such as zoning) to a wider EB-MSM context. The assignment of values to biophysical features of the marine environment allows the direct assessment of related management choices and may assist EB-MSM.A range of monetary valuation techniques have been proposed to reduce attributes of goods and services to a single metric. However, in the marine environment such an approach is often over simplistic, and thus less reductive techniques may be necessary. Rather than producing a single metric, the results of non-monetary assessments guide policy allowing weight to be given as necessary to potential areas of conflict and consensus.Strategies to take into account climate change effects and geohazard risks in EB-MSM have been applied or proposed worldwide. EB-MSM regimes must be alert to such risks and flexible to account for changes.  相似文献   
16.
农业气象服务效益评估方法研究   总被引:4,自引:0,他引:4  
科学、准确的对我国农业气象服务效益进行评估和分析,对政府和企业正确决策,提高农业气象防灾减灾能力,具有重要的作用和意义。结合农业气象服务的特点,采用剂量-反应分析和德尔菲法相结合的研究方法,研究提出了农业气象服务效益评估模式。该评估模式以典型单位的气象服务贡献率的实际测定值为参考值,运用专家评估法,由农业专家估测出气象服务在该农业生产中的贡献率,以此为基础分析评估出农业气象服务效益值。应用这一评估模式,对河南省农业气象服务效益进行了实证分析评估。结果表明,种植业气象服务贡献率为6.90 %,而后依次是牧业4.20 %、林业3.93 %、农林牧渔服务业3.36 %和渔业2.90 %。同时,分析研究了2007年以来,河南省农业气象服务效益的动态变化,研究表明,气象服务效益值随着农业产值的增加而不断提高,从2007年128.27亿元攀升至2010年191.65亿元,年均增速达到14.32 %。河南省农业气象服务平均贡献率保持在5.60 %-5.90 %之间,这一比率远高于全国,由此也说明了农业气象服务对河南省农业生产的重要作用。  相似文献   
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18.
Commercial interest in deep sea minerals in the area beyond the limits of national jurisdiction has rapidly increased in recent years. The International Seabed Authority has already given out 26 exploration contracts and it is currently in the process of developing the Mining Code for eventual exploitation of the mineral resources. Priority issues have so far been feasibility and profitability of this emerging industry, while relatively little consideration has been given as to how, and to an even lesser extent, whether deep seabed mining should proceed. This article makes a case that the global community should question and scrutinize the underlying assumption that deep seabed mining is going benefit humankind as a whole before commercializing the common heritage of humankind.  相似文献   
19.
Integrated water resources management: Concepts and issues   总被引:1,自引:0,他引:1  
After the describing the historical developments that led the development of Integrated Water Resources Management (IWRM), the paper defines this important concept. It subsequently deals with the thorny issue of water security as well as water conflict, after which the major issues over which thus far no consensus has been achieved are briefly reviewed. The paper concludes with an analysis of the role of the IAHS International Commission on Water Resources Systems (ICWRS) in promoting IWRM.  相似文献   
20.
Fish hatchery programs commonly are used to enhance depleted fish populations. While these programs are highly valued by the public, most likely due to their nonrestrictive approach to restoring a fishery, the effectiveness of these programs has been often questioned. This study investigates economic and ecological effectiveness of the Albemarle Sound/Roanoke River (AR) striped bass stocking program from 1981 to1996 as a case study.  相似文献   
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