Valuing ecosystem services
Overview
What are Mother Nature's life-support services worth? In one sense, their value is infinite. The Earth's economies would soon collapse without fertile soil, fresh water, breathable air, and an amenable climate. But "infinite" too often translates to "zero" in the equations that guide land use and policy decisions. Practitioners in the young field of ecological economics believe more concrete numbers are required to help nations avoid unsustainable economic choices that degrade both their natural resources and the vital services that healthy natural ecosystems generate.
In one of the first efforts to calculate a global number, a team of researchers from the United States, Argentina, and the Netherlands has put an average price tag of US$33 trillion a year on these fundamental ecosystem services, which are largely taken for granted because they are free. That is nearly twice the value of the global gross national product (GNP) of US$18 trillion [1]. (See How Much Are Nature's Services Worth? and Ecosystems Services: Free, But Valuable.)
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| Estimates of various Ecosystem Services | |
| Ecosystem services | Value (trillion $US) |
| Soil formation | 17.1 |
| Recreation | 3.0 |
| Nutrient cycling | 2.3 |
| Water regulation and supply | 2.3 |
| Climate regulation (temperature and precipitation) | 1.8 |
| Habitat | 1.4 |
| Flood and storm protection | 1.1 |
| Food and raw materials production | 0.8 |
| Genetic resources | 0.8 |
| Atmospheric gas balance | 0.7 |
| Pollination | 0.4 |
| All other services | 1.6 |
| Total value of ecosystem services | 33.3 |
| Source: Adapted from R. Costanza et al., "The Value of the World's Ecosystem Services and Natural Capital," Nature, Vol. 387 (1997), p. 256, Table 2. | |
References and notes
1. Robert Costanza et al., "The Value of the World's Ecosystem Services and Natural Capital," Nature, Vol. 387 (1997), p. 259.
2. Mark Sagoff, "Can We Put a Price on Nature's Services?," The Institute for Philosophy and Public Policy. Available online at: http//www.puaf.umd.edu/ippp/nature.htm (November 28, 1997).
3. Op. cit. 1, p. 255.
4. Op. cit. 1, p. 259.
5. Robert Goodland and Herman Daly, "Environmental Sustainability: Universal and Nonnegotiable," Ecological Applications, Vol. 6, No. 4 (1996), p. 1016.
6. Op. cit. 1, pp. 253-260.
7. Op. cit. 1, p. 256, Table 2.
8. Op. cit. 1, p. 259.
9. Stuart L. Pimm, "The Value of Everything," Nature, Vol. 387 (1997), p. 232.
10. Richard M. Stapleton, Protecting the Source: Land Conservation and the Future of America's Drinking Water (The Trust for Public Land, San Francisco, 1997), pp. 5-6.
11. E.B. Barbier et al., "An Economic Valuation of Wetland Benefits," in The Hadejia-Nguru Wetlands: Environment, Economy, and Sustainable Development of a Sahelian Flood Plain Wetland, G.E. Hollis et al., eds. (World Conservation Union-IUCN, Gland, Switzerland, 1993).