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Valuation of Ecosystem Services Presentation to Models and Modeling for the World Water Assessment Programme Joel D. Scheraga National Program Director U.S. EPA December 11-12, 2000 Ecosystem Services Ecosystem services refers to how humans benefit from ecosystems:
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Valuation of Ecosystem Services Presentation to Models and Modeling for the World Water Assessment Programme Joel D. Scheraga National Program Director U.S. EPA December 11-12, 2000
Ecosystem Services Ecosystem services refers to how humans benefit from ecosystems: “…a wide range of conditions and processes through which natural ecosystems, and the species that are part of them, help sustain and fulfill human life” - Daily et al., 1997
Ecosystem Services Ecosystem services relevant to freshwater ecosystems include: • recreation (including hunting and fishing) • intrinsic or existence values (value of something irrespective of any human use) • amenity functions • wildlife viewing • maintenance of biodiversity and landscape diversity • water quality protection and regulation of water flows • genetic material and maintenance of a gene pool • amelioration of weather and climate regulation
Ecosystem Services Ecosystem services (cont.): • pest control • fisheries • soil retention (erosion control), formation, and maintenance of fertility • storm protection, flood control and regulation of hydrologic cycles • nutrient cycling • cultural (e.g., aesthetic, artistic, spiritual, scientific values) • food and fiber production • medicines and pharmaceuticals
Purpose of Ecological Assessment • Evaluate how human activities affect ecosystems • Evaluate which of these changes are important • Provide decision makers with information about tradeoffs involved in their decisions • in ecological terms • in economic terms
Example of Difficult Tradeoff for Decision Makers Use of water to sustain ecosystems vs. Use of water for food production
Fundamental Problem of Economics • The allocation of scarce physical and human resources among competing and unlimited human wants and desires • Key concept: Scarcity • desired • limited in quantity • Water can be a scarce resource
Challenge for Policy Makers • Decide which use of scarce resources (e.g., water) is valued higher • Societal decision • Assessors can inform: Values human place on different resources, e.g., • survival of wildlife • ecosystem functions/services • adequate human nutrition • We can facilitate: Understanding of tradeoffs (nature & magnitude) inherent in any decision • Assessors’ job is not to make policy decisions
Need to Focus on Changes in Ecosystems • Humans depend upon ecosystems for their fulfillment and survival. • Without ecosystems, no living things could exist. • Valuation of total systems, however, is generally irrelevant to decision making. • Most decisions neither eliminate nor destroy complete ecosystems.
Important Caveat There are aspects of ecosystems that are valuable but may not be amenable to economic analysis Such circumstances may require: • other analysis and communication tools • other decision-making frameworks
Measuring the Economic Value of Ecosystem Services • Economic definition of value: the amount of compensation required to make individuals as well off after a change as before the change. • Value to society: determined by the sum of individual values when there is a marginal change in an ecological service (e.g., recreational fishing)
Values for Ecological Services: Categories and Examples • Market Use Values: • food, building materials (e.g., gravel), fuel, drinking water supplies, electric power generation, transportation of coal, tourism • Nonmarket Use Values: • recreation, fishing, swimming, boating, hunting, bird-watching, hiking, camping, sight-seeing, transportation and fuel; • flood control, mitigation of drought, stormwater treatment and/or retention, partial stabilization of climate, water purification, cycling of nutrients and minerals, flow of energy • Nonmarket Nonuse Values: • habitat value, scarcity value, option value, existence value, cultural value, historical value, biodiversity, intrinsic value, bequest value, philanthropic value
Valuing Changes in Ecological Services • Economists use several methods to measure people’s willingness to accept tradeoffs… • whether they are ecologists, economists, bird watchers, hikers, carpenters, baseball players, ballerinas, musicians, etc. • Prefer methods based on how people behave when faced with real-world tradeoffs • e.g., between ecological services and other goods • revealed preference approaches • When observed behavior does not reveal preferences: • survey techniques • stated-preference approaches
Methods for Valuing Changes in Ecological Services Revealed Preference • (Hedonic) Property Value • uses changes in private property values to estimate an implicit price for changes in ecological services • relies on “natural experiments” • Travel-Cost Method • observes recreators’ observed pattern of trips among available sites • accounts for observed variations in site characteristics, including ecological services
Methods for Valuing Changes in Ecological Services Stated Preference • Contingent Valuation • involves direct survey of individuals to elicit their “willingness to pay” for different levels of services • Stated Choice • Involves survey in which respondents are asked to express preferences among attributes that include specific ecological services (e.g., fish catch; protecting an endangered species) • Strength: respondents think in terms of tradeoffs • Researchers can identify equivalent tradeoffs by analyzing series of responses
Challenges in Translating Ecological Value to Economic Value • Conditions ideal when: • possible to describe or predict the ecological change accurately, • nature of ecological good/service that is lost/gained is understood, and • importance of the change can be quantified (e.g., monetized) or ranked • These ideal conditions seldom are met. • Three major challenges: • uncertainty • irreversibility and cumulative effects • issues of fairness (e.g., intergenerational equity, discounting, and environmental justice)
References • Ecological Assessment of Aquatic Resources: Application, Implementation, and Communication, Pellston Workshop, September 16-21, 2000 (forthcoming) • Nature’s Services: Societal Dependence on Natural Ecosystems, Gretchen C. Daily (ed.), Island Press, Washington, DC, 1997. • “Guidelines for Preparing Economic Analyses,” U.S. EPA. June 11, 1999 (draft)
Additional Information EPA’s Global Change Research Program: www.epa.gov/globalresearch