PARENT SESSION
Symposium #3: Ecological Theory and Restoration Ecology.

Organized by: MA Palmer, D Falk, and J Zedler
Monday, August 5. 8:00 AM to 11:30 AM. Leo Rich Theatre.

How much to restore: Economics of ecosystem services.

Roughgarden, Joan^*,1, ¹ Stanford University, Stanford, CA

ABSTRACT- Ecosystem restoration is usually subjected to intense scrutiny for costs, and the economic benefits must be exhibited to avoid the impression that restoration is an economic drain. For some ecosystem services, especially aggregates like total biomass and productivity, adding species shows a decreasing marginal return, implying that an economically optimal level of species restoration exists. In contrast, adding land area to the zone of restoration can show an increasing marginal return, because each unit of area increases in value as the total area is increased, as a result of the species-area relation. Valuing species individually, instead of solely in terms of aggregate properties, greatly increases the economic case for restoration. Species become more valuable individually as a system becomes more diverse because spices, perfumes, dyes, and drugs originate in species interactions, which become more numerous as the square of the species diversity. The loss of stability to a community as it becomes more diverse, and the increased presence of keystone species, makes restoration and conservation more expensive though, and sets an upper bound on the economically optimal biodiversity. Some additional economic support for restoration comes from arguments about maintaining a diverse inventory as insurance for changing tastes reflected in changing demands for ecosystem goods and services. Conservationists should advertise the benefits of ecosystem services in preference to artificial substitutes to increase the demand for nature.

KEY WORDS: Ecological-Economics, Restoration, Ecosystem Services, Cost/Benefit