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Valuing Ecosystem Services. Geoffrey Heal for EPA-SAB. What is “value”?. Multidimensional Many aspects of the value of e-s-s Includes a range of ethical sources of value as well as economic aspects of value –
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Valuing Ecosystem Services Geoffrey Heal for EPA-SAB
What is “value”? • Multidimensional • Many aspects of the value of e-s-s • Includes a range of ethical sources of value as well as economic aspects of value – • “Intrinsic value” or Kantian imperatives may be motivation for legislation as with the ESA • Focus on economic aspects of value
Total Economic Value • TEV – • Use and non-use values • Use values include recreation, fishing, water purification • Non-use values include existence values • Quite comprehensive – more that generally recognized by non-economists
Classification of Total Economic Values for Aquatic Ecosystem Services SOURCE: Adapted from Barbier et al., (1997) and Barbier (1994).
Valuation methods • Market methods, revealed preferences – relatively rare (non-market, public goods) • Non-market methods, stated preferences • Travel costs • Hedonics • Stated preference methods – • Contingent valuation and conjoint analysis
What to measure • Willingness to pay or • Willingness to accept • Depends primarily on property rights, expectations • WTA > WTP, which is bounded by income while WTA is not
Measurement • We are always interested in measuring the values of changes in e-s-s that will result from human activities • The focus is on changes in e-s-s from human activities and on • Valuing the changes in e-s-s
Difficulty • Main analytical difficulty seems to be in linking economic and ecological analyses • Need to use ecological analysis to predict response of e-s-s to human activities • Ecologists tend to focus on impact of human actions on ecosystem structure and function
Difficulty • Need ecologists to predict D(e-s-s) resulting from policy measures • Is often complex and stretches science to the limits • Then use economics to value (as WTA or WTP) this D(e-s-s) by a suitable valuation method