Complex systems and valuation

Ecological and economic systems are undeniably complex. Whereas a goal of delineating 'ecosystem services' is to make readily apparent some of the important ways in which ecosystems underpin human welfare, insights are also gained by appreciating the nonlinear dynamic properties of ecosystems. In this paper, we review some of the relevant characteristics of complex systems. Ecosystems and economic systems share many properties, but valuation has typically been driven by short-term human preferences. Here we argue that as the force of humanity increases on the planet, ecosystem service valuation will need to switch from choosing among resources to valuing the avoidance of catastrophic ecosystem change. (C) 2002 Elsevier Science B.V. All rights reserved.