Biodiversity and ecosystem services: Whither the promised biophysically and socially informed valuation?

Background/Question/Methods: The valuation of biodiversity and ecosystem services (ES) is at the center of many efforts to communicate the importance of ecosystems and the implications of environmental change for humanity. Researchers have argued convincingly that ES research ought to include such valuation, which should be linked to biophysical science, and explicitly connect social change with ecological change. But despite such calls for socially and biophysically grounded valuation, ES has become synonymous to many audiences with ‘putting a price tag on nature’, which evokes disdain and discomfort from many. We conducted a systematic literature review to assess the proportion of ES studies that (a) includes valuation, (b) is grounded in biophysical science of ES change and/or (c) in social science of such change. We compared these proportions with that of (d) using ‘ES’ in a perfunctory manner as a symbolically loaded keyword. Our sample was a stratified random sample of 306 ES studies (published papers using ES as a keyword).

Results/Conclusions: The ratio of studies explicitly mentioning ES without characterizing ES either biophysically or socially (in ‘perfunctory’ fashion) to those valuating ES with biophysical grounding was ~26:1. Specifically, in the studies reviewed, there was little biophysical characterization of processes explicitly relevant for ES (20.8 ± 2.5 %), far less valuation (7.7 ± 1.6 %), and minute fractions doing biophysically-grounded valuation (2.7 ± 1.0 %) or characterizing relevant social patterns or processes (2.4 ± 0.9 %). The vast majority of studies were instead using the language of ES to symbolically valorize or signal the importance of ES and/or the study (71.0 ± 2.7 %). While the absolute number of ostensibly ES-related studies has increased greatly, these ratios have not changed significantly over time, suggesting that the field is apparently not maturing in these ways. The bulk of ES research is not living up to its promise or potential. For ES research to improve understanding of the values of ecosystems and ES, and to improve decision-making, it will require a major expansion of existing ES research to characterize the linked biophysical and social dynamics underpinning ES, and to employ a diverse set of approaches to ES valuation and decision-making.