ABSTRACT
Many hope that the ecosystem services framework will provide a new and generous source of conservation funding. Heather Tallis and Peter Kareiva (2005) write that “realization of the market worth of ecosystem services has the potential to increase conservation funding by orders of magnitude”. This enthusiasm has sparked an impressive volume of work within the ecosystem service framework (Turner and Daily, 2008). Fisher and co-authors (2009) document an exponential increase in the number of published papers employing the terms “ecosystem services” or “ecological services”, beginning from essentially none in the early 1980s to more than 250 in 2007, the last year for which they have data. Some rough idea of the currency of the term can be gleaned from the fact that entering “ecosystem services” in the Google search engine returns about 4.7 million entries.2 The Millennium Ecosystem Assessment (MA), a multi-year, multi-million dollar international undertaking involving over 1,300 scientists from around the world was conducted to assess the consequences of ecosystem change, and consequent alterations in the flow of ecosystem services, for human well-being (MA, 2005). This work may continue under a recently proposed “intergovernmental platform on biodiversity and ecosystem services” (IPBES), modeled on the Nobel-prize-winning Intergovern-
mental Panel on Climate Change (IPCC). In November 2008 representatives of 78 nations and 25 international NGOs met to consider establishment of an IPBES (UNEP, 2008a). At the meeting a “program of work and budget” of approximately $18.4 million was presented (although not yet adopted) (UNEP, 2008b). Organizations around the world are adopting an ecosystem services approach to ecological decision-making. Yet the elements of that approach are not as settled as its widespread adoption might make it appear. One often encounters passages such as the following: “Although the societal benefits of native ecosystems are clearly immense, they remain largely unquantified for all but a few services” (Ricketts et al., 2004, emphasis added; see also Kareiva and Ruffo, 2009; Daily et al., 2009). But if benefits are “largely unquantified”, what is the basis for concluding that they are “clearly immense”? Is there really much evidence supporting the contention that the services supplied by natural ecosystems are of great value and that they are being squandered by unwise land-use decisions? In this chapter I suggest that evidence to that effect remains sparse. This is so for several reasons, and I will consider them in turn. The first is that many contributions to the literature on ecosystem service values would appear to be intended to motivate research on ecosystem services rather than to document the findings of such research. There are certainly numerous, and in many instances eloquent, statements of the hypothesis that natural ecosystems provide valuable services, but fewer careful tests of that hypothesis. In some studies the interpretation of evidence concerning ecosystem service values is problematic. It is worth underscoring that evidence of ecosystem service values will only motivate different conservation decisions if such values outweigh costs. It is not sufficient simply to note that there is some value to conserving what is already in place without comparing that value to other possibilities. Closely related to the above observation is the economic truism that “value is determined on the margin”. The relevant concern is typically not that biodiversity or ecosystem services will perish in their entirety. Any monetary estimate of such a calamity would necessarily be, to borrow Michael Toman’s (1998) characterization, a “serious underestimate of infinity”. The relevant policy question, then, is whether preserving specific components of ecosystems provides benefits in excess of those that would arise from their forgone uses. If ecosystem services are not assigned their true value in land-use decisionmaking, it is because such services are public goods; that is, they are benefits which, when supplied by one person are necessarily accessible to many. Yet the more compact the scale on which such public goods are provided – the fewer members of the “public” who benefit from their provision – the less likely it is that ecosystem services will be underprovided. Consequently, we should be most concerned about the provision of ecosystem services whose benefits are very widely dispersed. This observation, in turn, leads to a couple of other issues. First, there is what I call below a “paradox of valuation”. The things we would most like to be able to place an economic value on are those public goods whose benefits are the
most widely dispersed. But these are precisely the goods whose value is most difficult to estimate. Second, the most compelling argument for conserving relatively pristine ecosystems may prove to be that they provide the global public goods of carbon sequestration and biodiversity protection. If this is, in fact, the most important argument for conservation, however, the ecosystem service framework does not appear to be adding much new to the debate on conservation policy. This last observation poses the main question motivating this chapter. How does adopting the ecosystem service framework alter the ways in which we think about conservation policy? If the point is simply that we ought to regard natural ecosystems as assets that provide value to society and should, therefore, compete with alternative land uses as we make choices about how to allocate the earth’s surface among our wants and needs, the argument is unexceptionable. It is also not novel, however. Underscoring such a fundamental principle is useful, but it alone cannot account for current enthusiasm for the ecosystem service framework. That enthusiasm derives, rather, from the sense that the ecosystem service framework has already demonstrated, or can soon be expected to demonstrate, the general economic superiority of conservation to alternative land uses. Most of the remainder of this chapter is devoted to considering and, generally, rebutting these assertions. As these are controversial points, I should hasten to point out a handful of caveats. I most certainly do not dispute that the services of natural ecosystems are valuable to humanity. Nor do I dispute that the services of some such ecosystems are more valuable than are any alternative uses that might be made of the areas they occupy. Consequently, there are surely instances in which land use could be made more rational and, generally, socially beneficial by undertaking public policy to preserve natural habitats. What has not been satisfactorily established is the generality of such propositions. In the body of this chapter I pursue two major themes. The first is that many well-known tracts on ecosystem services do not, in fact, make a general and compelling case for their economic value. The second is that there is a good reason for the first observation: valuing ecosystem services is an extraordinarily difficult undertaking. In the final section of the chapter I return to my main question in light of these observations. What does an ecosystem service framework imply for conservation policy, and does adopting it move the debate forward?
