Many critiques of the protected area model suggest that parks have been thought of in ways too abstracted from people, failing to recognize the significance of land and other resources to local cultures, livelihoods, and systems of meaning. Over the past twenty years, one response to these critiques within mainstream environmentalism has been a shift into more market-based logics. According to these logics, the best way to protect nature may not be by drawing strict boundaries around wilderness areas, but rather, by making nature subject to some of the laws that govern market transactions. The movement to create markets for Ecosystem Services (i.e., the services that are provided by environments, including water purification and retention, soil fertility, carbon sequestration, coastal protection) expresses this idea.

As you’ll read about in the Noorgaard piece this week, the idea of Ecosystem Services was first used as a metaphor to illustrate just how dependent human society is on the services provided by our environments. Other early work attempted to index the total value of these services. One 1997 article by Costanza and colleagues, for instance, calculated that Ecosystem Services had an economic value of more than $33 trillion per year (a figure larger than global gross domestic product in that year). As they wrote: “Because ecosystem services are not fully ‘captured’ in commercial markets or adequately quantified in terms comparable with economic services and manufactured capital, they are often given too little weight in policy decisions. This neglect may ultimately compromise the sustainability of humans in the biosphere. The economies of the Earth would grind to a halt without the services of ecological life-support systems, so in one sense their total value to the economy is infinite.”

In subsequent work, the Ecosystem Services concept has been used not only to communicate the significance of nature (i.e. as an expression of what would be lost financially) but as a way to compare the relative value of different land or resource uses. Translating ecosystem services into dollar signs, in other words, makes it possible to compare the protection of ecosystem services with the economic value of resource extraction. This week I invite you to think through the merits and limitations of this approach. As the Ecosystem Services concept has taken hold over the past two decades, critiques have surfaced that help to complicate some of the initial enthusiasm surrounding the concept. Try to engage with these critiques as you read Norgaard and McCauley. Engage as well with Constanza and colleagues’ rebuttal. Are payments for ecosystem services (or other ecological markets for that matter) a good idea? What are their pros and cons, strengths, limitations?