计量经济分析 = Econometric analysis

Freshwater biodiversity is the over-riding conservation priority during the International Decade for Action - 'Water for Life' - 2005 to 2015. Fresh water makes up only 0.01% of the World's water and approximately 0.8% of the Earth's surface, yet this tiny fraction of global water supports at least 100000 species out of approximately 1.8 million - almost 6% of all described species. Inland waters and freshwater biodiversity constitute a valuable natural resource, in economic, cultural, aesthetic, scientific and educational terms. Their conservation and management are critical to the interests of all humans, nations and governments. Yet this precious heritage is in crisis. Fresh waters are experiencing declines in biodiversity far greater than those in the most affected terrestrial ecosystems, and if trends in human demands for water remain unaltered and species losses continue at current rates, the opportunity to conserve much of the remaining biodiversity in fresh water will vanish before the 'Water for Life' decade ends in 2015. Why is this so, and what is being done about it? This article explores the special features of freshwater habitats and the biodiversity they support that makes them especially vulnerable to human activities. We document threats to global freshwater biodiversity under five headings: overexploitation; water pollution; flow modification; destruction or degradation of habitat; and invasion by exotic species. Their combined and interacting influences have resulted in population declines and range reduction of freshwater biodiversity worldwide. Conservation of biodiversity is complicated by the landscape position of rivers and wetlands as 'receivers' of land-use effluents, and the problems posed by endemism and thus non-substitutability. In addition, in many parts of the world, fresh water is subject to severe competition among multiple human stakeholders. Protection of freshwater biodiversity is perhaps the ultimate conservation challenge because it is influenced by the upstream drainage network, the surrounding land, the riparian zone, and - in the case of migrating aquatic fauna - downstream reaches. Such prerequisites are hardly ever met. Immediate action is needed where opportunities exist to set aside intact lake and river ecosystems within large protected areas. For most of the global land surface, trade-offs between conservation of freshwater biodiversity and human use of ecosystem goods and services are necessary. We advocate continuing attempts to check species loss but, in many situations, urge adoption of a compromise position of management for biodiversity conservation, ecosystem functioning and resilience, and human livelihoods in order to provide a viable long-term basis for freshwater conservation. Recognition of this need will require adoption of a new paradigm for biodiversity protection and freshwater ecosystem management - one that has been appropriately termed 'reconciliation ecology'.

https://www.cambridge.org/core/services/aop-cambridge-core/content/view/96AA265E3D88C95FB802E7A73CCB4332/S1464793105006950a.pdf/div-class-title-freshwater-biodiversity-importance-threats-status-and-conservation-challenges-div.pdf

Freshwater biodiversity: importance, threats, status and conservation challenges

Framework Convention on Climate Change

This paper gives an overview of the value of ecosystem services of 10 main biomes expressed in monetary units. In total, over 320 publications were screened covering over 300 case study locations. Approximately 1350 value estimates were coded and stored in a searchable Ecosystem Service Value Database (ESVD). A selection of 665 value estimates was used for the analysis. Acknowledging the uncertainties and contextual nature of any valuation, the analysis shows that the total value of ecosystem services is considerable and ranges between 490 int$/year for the total bundle of ecosystem services that can potentially be provided by an ‘average’ hectare of open oceans to almost 350,000 int$/year for the potential services of an ‘average’ hectare of coral reefs. More importantly, our results show that most of this value is outside the market and best considered as non-tradable public benefits. The continued over-exploitation of ecosystems thus comes at the expense of the livelihood of the poor and future generations. Given that many of the positive externalities of ecosystems are lost or strongly reduced after land use conversion better accounting for the public goods and services provided by ecosystems is crucial to improve decision making and institutions for biodiversity conservation and sustainable ecosystem management.

https://www.cbd.int/financial/values/g-valueglobal.pdf

Global estimates of the value of ecosystems and their services in monetary units

Foundations Of Statistics

http://www.unepscs.org/Economic_Valuation_Training_Materials/06%20Readings%20on%20Economic%20Valuation%20of%20Coastal%20Habitats/23-Economic-Value-Wetland-Services.pdf

The economic value of wetland services: a meta-analysis

Each World Resources Institute Report represents a timely, scholarly treatment of a subject of public concern. WRI takes responsibility for choosing the study topics and guaranteeing its authors and researchers freedom of inquiry. It also solicits and responds to the guidance of advisory panels and expert reviewers. Unless otherwise stated, however, all the interpretation and findings set forth in WRI publications are those of the authors. • ACKNOWLEDGMENTS Two of the authors of this report—Dr. Ham-mond and Dr. Adriaanse—participated in the Project on Indicators of Sustainable Development of the Scientific Committee on Problems of the Environment (SCOPE), an international scientific effort intended to contribute to the indicator activities of the U.N. Commission on Sustainable Development. An earlier version of this report was reviewed by the SCOPE project and provided background for an international policy meeting on indicators of sustainable development hosted by the Belgium and Costa Rican governments in collaboration with SCOPE and the U.N. Environment Programme. Dr. Hammond and Dr. Adriaanse have benefited from the advice and comments of their international colleagues, includ-ern, all of whom provided valuable comments and encouragement on earlier drafts of this report. Our gratitude is also extended to those within WRI who helped with this report—to Dan Tunstall for their reviews, to Kathleen Cour-rier for her skillful editing, to Maggie Powell for preparation of figures, and to Sharon Bellucci for desktop production and support throughout the project. Of course, we alone bear responsibility for the final result. FOREWORD All across the United States, policy-makers and pundits sit up and take notice when the Dow Jones inches up, housing starts plummet, or unemployment rates rise—and millions of Americans rethink personal financial decisions. In every country, leaders find changes in gross national product (GNP) similarly riveting. These economic indicators show the power of a single number when its importance is widely understood. Yet, no remotely similar numbers exist to indicate how the environment is faring. A significant attempt to bridge this knowledge gap is Environmental Indicators: A Systematic Approach to Measuring and Reporting on Environmental Policy Performance in the Context of Sustainable Development by Allen L. Hammond, director of WRI's Resource and Environmental Information program; Albert Adriaanse, senior ministerial advisor to the Netherlands' Directorate for the Environment; Eric Rodenburg, WRI senior policy analyst; Dirk Bryant, WRI policy analyst; and Richard Woodward of the University of Wiscon-sin. The authors begin by laying out a conceptual approach for …

Environmental indicators : a systematic approach to measuring and reporting on environmental policy performance in the context of sustainable development

The national income accounting framework assesses overall economic performance. It depreciates man-made capital but does not consider depletion of natural resources. This framework is especially faulty in countries like Costa Rica where natural resources constitute the main economic assets. An accounting framework which incorporates natural resources reveals that between 1970-1989 Costa Rica lost natural resources equalling more than one years gross domestic product (184 billion colones = US $4.1 billion). These natural resources included forests soils and fisheries. Yet this is only a small percentage of what actually was lost because the economists had no value to use for estimates of other natural resource losses such as wildlife habitat. During 1983-1989 the mean annual depreciation of forests soils and fisheries was 70% greater than the mean annual depreciation for 1970-1982 (11.2 billion colones vs. 6.5 billion colones). Since timber became more rare and thus more expensive rising costs of deforestation made up much of the increased annual depreciation rate. Mean soil depreciation costs were approximately the same from 1970-1989 (2.6 billion colones). Yet in 1984 soil depreciation costs constituted 9% of value added in agriculture. There were no restrictions on overfishing during the study period which resulted in complete destruction of the economic value of fisheries. During 1970-1989 natural resource depreciation rose a mean 6.4%/year. Since the traditional accounting system disregarded the loss of Costa Ricas natural resources it inflated actual net capital formation by >41%. Economic development programs in Costa Rica have abandoned its land forests and seas which are three of the countrys sources of wealth. Yet national policymakers still do not understand the relationship between economic development and natural resources.

Accounts Overdue : Natural Resource Depreciation in Costa Rica

Environmental economists have traditionally addressed the issue of choice under uncertainty by applying the expected utility hypothesis. When policymakers face a panel of experts with widely divergent beliefs, the problem may more accurately be described as a case of choice under pure uncertainty. Arrow and Hurwicz (1972) demonstrate that rational choice criteria under pure uncertainty will focus on the extremes of the state space, not the midpoint as is typically assumed. Using Nordhaus's DICE model, uncertainty-based choices about global warming policies are evaluated. Linkages to the safe minimum standard and the precautionary principle are also discussed.

How to Decide When Experts Disagree: Uncertainty-Based Choice Rules in Environmental Policy

The use of transferable discharge permits as a water pollution control policy is rapidly increasing in the United States Drawing on evidence from existing water quality trading programs, this paper provides a taxonomy of the forms that such markets take Four main structures are identified: exchanges, bilateral negotiations, clearinghouses, and sole-source offsets Each of these structures has its own strengths and weaknesses; none is optimal for all scenarios Since market structure is largely determined by a program's rules, policy makers should be aware of the differences between these structures and the conditions under which each comes to be

Richard T. Woodward

Papers

The economic value of wetland services: a meta-analysis

Environmental indicators : a systematic approach to measuring and reporting on environmental policy performance in the context of sustainable development

Accounts Overdue : Natural Resource Depreciation in Costa Rica

How to Decide When Experts Disagree: Uncertainty-Based Choice Rules in Environmental Policy

Market Structures for U.S. Water Quality Trading