Nutrient recycling, habitat for plants and animals, flood control, and water supply are among the many beneficial services provided by aquatic ecosystems. In making decisions about human activities, such as draining a wetland for a housing development, it is essential to consider both the value of the development and the value of the ecosystem services that could be lost. Despite a growing recognition of the importance of ecosystem services, their value is often overlooked in environmental decision-making. This report identifies methods for assigning economic value to ecosystem servicesâ€"even intangible onesâ€"and calls for greater collaboration between ecologists and economists in such efforts.

Cases from South Asia.

Biodiversity loss is one of the major resource problems facing the world, and the policy options available are restricted by inappropriate economic tools which fail to capture the value of species and their variety. This study describes in non-technical terms how cost-benefit analysis techniques can be applied to species and species loss, and how they provide a measure of the efficiency of conservation measures. Only when conservation can be shown to pass such a basic economic test, the authors claim, will it be incorporated into policies.;David Pearce has also written Blueprint for a Green Economy.

Water provides benefits as a commodity for agriculture, industry, and households, and as a public good such as fisheries habitat, water quality and recreational use. To aid in cost-benefit analysis under conditions where market determined price signals are usually unavailable, economists have developed a range of alternative valuation methods for measuring economic benefits. This volume provides the most comprehensive exposition to-date of the application of economic valuation methods to proposed water resources investments and policies. It provides a conceptual framework for valuation of both commodity and public good uses of water, addressing non-market valuation techniques appropriate to measuring public benefits - including water quality improvement, recreation, and fish habitat enhancement. The book describes the various measurement methods, illustrates how they are applied in practice, and discusses their strengths, limitations, and appropriate roles. In this second edition, all chapters have been thoroughly updated, and in particular the coverage of water markets and valuation of ecosystem services from water has been expanded. Robert Young, author of the 2005 edition, has been joined for this new edition by John Loomis, who brings additional expertise on ecosystem services and the environmental economics of water for recreational and other public good uses of water.

"The international community has committed itself to achieve, by 2010, a significant reduction of the current rate of biodiversity loss at the global, regional, and national levels. Yet, despite growing awareness, and major efforts in all countries, the latest evidence indicates that biodiversity continues to be lost at a terrifying pace, resulting in what some call the greatest mass extinction since dinosaurs roamed the planet, 65 million years ago. A range of methods have been developed to value ecosystems, and the services they provide, as well as the costs of conservation. The methods available are increasingly sensitive, and robust, but they are often incorrectly used. One reason is poor understanding of the purposes of valuation and what questions it can, or cannot, answer. As a result, decision makers may get misleading guidance on the value of ecosystems, and their conservation. In this context, the Bank, IUCN-The World Conservation Union, and the Nature Conservancy have worked together to clarify the aims and uses of economic valuation, focusing on the types of questions that valuation can answer, and the type of valuation that is best suited to each purpose. How Much is an Ecosystem Worth? is the result of that cooperation. It aims to provide guidance on how economic valuation can be used to address specific, policy-relevant questions about nature conservation."