This chapter investigates whether the growing enthusiasm for ecosystem services recently expressed by conservation NGOs and international institutions is supported by evidence. Ecosystem services—the benefits humans receive from nature—have become the darlings of conservation on the assumption that the valuation of selected services may justify protecting land. A critical examination of a random sample of monetary valuations for regulating ecosystem services such as pollution treatment, finds that only onethird can be considered reliable, and that only ten percent of monetary value estimates can be transferred to other contexts. This suggests that the overall evidence base for assigning monetary value to nature is limited. Furthermore, diminishing returns, high opportunity costs, and technological substitutes might limit the amount of conservation that can be justified on the basis financial assessments of ecosystem services. As such, this chapter concludes that ecosystem services as a conservation strategy should not be embraced uncritically.
Diminishing returns
