Ecosystem Goods and Services and Their Limits

H umans receive vital goods and services from both managed and natural ecosystems (e.g., Krutilla 1967; Daily 1997) and have become, inadvertently or deliberately, managers of essentially all of the terrestrial ecosystems of the world (Vitousek et al. 1994, 1997b; Carpenter et al. 1998; Tilman et al. 2001). In this chapter we consider the forces that influence the flows of ecosystem goods and services and the greater social welfare to be derived from policies that maximize the net value of the flows of these goods and services.