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201.
论述了大气监测分析方法标准化研究的特点、内容、样品采集方法和保存条件,样品预处理方法和测定条件,干扰试验、方法的基本特征参数第一轮测定、实际样品的测定等问题。 相似文献
202.
环境质量消费的经济学分析 总被引:3,自引:0,他引:3
以理性经济人,环境质量的需求和供给可以充分市场化,环境质量与地租正相关为理论假并把消费者抽象为高,低收入两个团体,通过建立理论模型来探讨消费者收入水平,环境质量的供给特性和环境质量消 这间的一般规律,结果表明(1)消费者收为公共物品,它 给方式也影响实际消费,由于环境质量存在空间差异,这种影响可以通过空间迁移选择来体现;(4)政府通过管理来调控环境质量供给,需求和消费的再分配。 相似文献
203.
DAVID NEWBURN‡ SARAH REED† PETER BERCK ADINA MERENLENDER† 《Conservation biology》2005,19(5):1411-1420
Abstract: Incentive-based strategies such as conservation easements and short-term management agreements are popular tools for conserving biodiversity on private lands. Billions of dollars are spent by government and private conservation organizations to support land conservation. Although much of conservation biology focuses on reserve design, these methods are often ineffective at optimizing the protection of biological benefits for conservation programs. Our review of the recent literature on protected-area planning identifies some of the reasons why. We analyzed the site-selection process according to three important components: biological benefits, land costs, and likelihood of land-use change. We compared our benefit-loss-cost targeting approach with more conventional strategies that omit or inadequately address either land costs or likelihood of land-use change. Our proposed strategy aims to minimize the expected loss in biological benefit due to future land-use conversion while considering the full or partial costs of land acquisition. The implicit positive correlation between the likelihood of land-use conversion and cost of land protection means high-vulnerability sites with suitable land quality are typically more expensive than low-vulnerability sites with poor land quality. Therefore, land-use change and land costs need to be addressed jointly to improve spatial targeting strategies for land conservation. This approach can be extended effectively to land trusts and other institutions implementing conservation programs. 相似文献
204.
Valuation of Ecological Resources and Functions 总被引:8,自引:0,他引:8
Michael J. Scott Gordon R. Bilyard Steven O. Link Carlos A. Ulibarri Howard E. Westerdahl Paolo F. Ricci Harold E. Seely 《Environmental management》1998,22(1):49-68
/ Ecological resources are natural resources that provide certain necessary but overlooked system maintenance functions within ecosystems. Environmental economics is in search of an appropriate analysis framework to determine economic values of such resources. This paper presents a framework that estimates and compiles the components of value for a natural ecosystem. The framework begins with the ecological processes involved, which provide functions within the ecosystem and services valued by humans. We discuss the additive or competive nature of these values, and estimate these values through conventional and unconventional techniques. We apply the framework to ecological resources in a shrub-steppe dryland habitat being displaced by development. We first determine which functions and services are mutually exclusive (e.g., farming vs soil stabilization) and which are complementary or products of joint production (e.g., soil stabilization and maintenance of species). We then apply benefit transfer principles with contingent valuation methodology (CVM), travel cost methodology (TCM), and hedonic damage pricing (HDP). Finally, we derive upper-limit values for more difficult-to-value functions through the use of human analogs, which we argue are the most appropriate method of valuation under some circumstances. The highest values of natural shrub-steppe habitat appear to be derived from soil stabilization.KEY WORDS: Natural resource economics; Ecological economics; Ecological resources; Shrub-steppe; Environmental valuation; Cost; Benefit; Value 相似文献
205.
John B. Loomis 《Journal of the American Water Resources Association》1998,34(5):1007-1014
ABSTRACT: Sound water resource management requires comparison of benefits and costs. Many of the perceived benefits of water relate to providing instream flow for recreation and endangered fish. These uses have value but no prices to guide resource allocation. Techniques to estimate the dollar values of environmental benefits are presented and illustrated with several case studies. The results of the case studies show that emphasis on minimum instream flow allocates far less than the economically optimum amount of water to instream uses. Studies in Idaho demonstrated that optimum flows that balance benefits and costs can be ten times greater than minimum flows. The economic benefits of preserving public trust resources outweighed the replacement cost of water and power by a factor of fifty in California. While it is important to incorporate public preferences in water resource management, these economic survey techniques provide water managers with information not just on preference but how much the public is willing to pay for as well. This facilitates comparison of the public costs and benefits of instream flows. 相似文献
206.
Modeling joint production of wildlife and timber 总被引:2,自引:0,他引:2
Darek J. Nalle Claire A. Montgomery Jeffrey L. Arthur Stephen Polasky Nathan H. Schumaker 《Journal of Environmental Economics and Management》2004,48(3):997
Production of marketed commodities and protection of natural systems often conflict. A focus on only one goal can result in large losses in other goals and may result in inefficient and unsustainable outcomes. In this paper, we develop a method that combines economic and ecological models in a dynamic and spatial analysis to evaluate land use decisions and find cost-effective alternatives for which it is not possible to do better on one objective without harming another objective. The method is demonstrated using timber production and species conservation on a forested landscape over a 100-year planning horizon. Current land use strategies are simulated and compared with cost-effective alternatives. The approach is compared to a static reserve approach, similar to previous studies, and found to produce substantially more efficient management strategies for the case study landscape. 相似文献
207.
湿地服务价值评估的复杂性及研究进展 总被引:7,自引:0,他引:7
湿地服务价值评估具有重要的理论意义和应用价值。由于湿地具有类型多样、分布广泛和过程复杂等特点,湿地服务价值评估极具复杂性。主要表现为:湿地科学是一门年轻的科学,其过程与功能研究有待深入;对生态系统服务及其价值认识上还存在分歧;湿地服务价值研究具有多学科交叉的特点等。近年来,国内外湿地服务价值评估发展很快,取得了丰硕的研究成果,但也存在着一些问题与不足,如对湿地研究成果的利用不够充分;评估理论和方法有待完善;评估标准和评估结果差异较大等。因此,今后湿地服务价值评估研究应该将重点放在理论探索和方法完善方面,对应用研究加强引导和规范。从湿地生态系统过程与功能的机理入手,认真研究和改进湿地服务价值评估的手段、方法和技术,使湿地服务价值评估结果更具说服力、可比性和实用性,为湿地的科学管理,生态补偿机制的制定以及社会经济可持续发展提供有力支持。 相似文献
208.
Despite the fact that all successful, documented cases of industrial symbiosis to this day have been self-organizing, some authors and development officials have suggested that increased public planning might deliver better results in this respect than spontaneously evolved market coordination. This paper takes an historical approach to suggest that comprehensive planning is unlikely to live up to the expectations of its proponents.The essay is structured as follows. The first section provides short case studies of industrial symbiosis in highly different economic and institutional settings, the essentially free-market regime of Victorian England and communist Hungary (1948–1989). The available evidence suggests that market coordination proved much more favorable to the emergence of industrial symbiosis, despite the elaboration of a comprehensive policy to that effect in Hungary. Insights derived from the so-called “Austrian” critique of central planning are then used to explain this paradox. The analysis presented suggests that the Hungarian planners’ failure was not so much the result of the bad implementation of sound policies, but the logical outcome of a top-down approach’s shortcomings. Policy implications for the public planning of industrial symbiosis in a mixed economy are then derived and the case for self-organization is found more compelling. The creation of more innovative institutions that will force firms to “internalize their externalities” while leaving them the necessary freedom to innovate is viewed as an urgently needed and promising path towards increased, sustainable reuse of industrial by-products. 相似文献
209.
Many trace constituents other than carbon dioxide affect the radiative budget of the atmosphere. The existing international agreement to limit greenhouse gases, the Kyoto Protocol, includes carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), sulfur hexafluoride (SF6) and credit for some carbon sinks. We investigate technological options for reducing emissions of these gases and the economic implications of including other greenhouse gases and sinks in the climate change control policy. We conduct an integreated assessment of costs using the MIT Emissions Prediction and Policy Analysis (EPPA) model combined with estimates of abatement costs for non-CO2 greenhouse gases and sinks. We find that failure to take advantage of the other gas and sink flexibility would nearly double aggregate Annex B costs. Including all the GHGs and sinks is actually cheaper than if only CO2 had been included in the Protocol and their inclusion achieves greater overall abatement. There remains considerable uncertainty in these estimates, the magnitude of the savings depends heavily on reference projections of emissions, for example, but these uncertainties do not change the overall conclusion that non-CO2 GHGs are an important part of a climate control policy. 相似文献
210.
Robert J. Imeson Jeroen C.J.M. Van Den Bergh Jeljer Hoekstra 《Environmental Modeling and Assessment》2002,7(4):259-271
An overview of the structure and elements of integrated models aimed at studying fishery management policies using static and dynamic optimisation techniques is presented. Continuous and discrete time models are considered under both open-access and sole-owner settings. A variety of economic and biological processes that affect the fishery as a whole is examined. It turns out that overseeing important fish population characteristics such as metapopulation dynamics and multi-species interaction can lead to serious misrepresentation of the fishery and suboptimal controls. Adequate understanding of the economic conditions and considerations potentially affecting the fishermen is necessary to model their behaviour and address their concerns. Misrepresentation of these economic and biologic processes will have an impact on the success of management policies in attaining a sustainable fish population. 相似文献