The science behind payments for ecosystem services programs: A global survey

Background/Question/Methods

One of the most challenging problems facing sustainability is establishing mechanisms for monitoring the consumption of ecosystem goods and services.  A widely adopted and rapidly evolving approach is Payments for Ecosystem Services (PES) projects. PES represents a mechanism for monetizing the value of ecosystem services leading to land management practices that protect or increase the provision of select ecosystem services. The science underlying ecosystem services has been the subject of many studies, however, the degree to which ecosystem science has been integrated into the design, development, and monitoring of PES projects has not been investigated systematically. If the criteria for establishing success are not founded on solid scientific principles, the long-term provisioning of services from a PES project may be compromised and thereby undermine the sustainable development goals of the project.  We undertook an investigation of PES projects based on three classes of ecosystem services: biodiversity, water, and carbon. The goal was to better understand the extent to which ecosystem science has been integrated into the development, planning, and ongoing monitoring of existing PES projects. These issues are of concern because they influence the ability to “scale-up” and the capacity for project success in the long-term.

Results/Conclusions

A global set of 300 projects were examined. Only 84 were amenable to analysis as reporting was often incomplete with respect to data, methods, and monitoring.  Our results suggest that the lack of uniformity and available scientific information hinders the ability to evaluate the likely effectiveness of a PES program, its ability to scale up as programs expand, and to determine the sustainability of the project. While the heterogeneity of data make assessing the role of science in the overall success of PES programs difficult, extrapolating from the longest standing cases with perceived ecological integrity, the following should be considered when designing a PES program: Instigating threat assessments to incorporate knowledge of ecosystem dynamics and ecological tradeoffs; Monitoring beyond the particular service to understand full impact of project. i.e. co-benefits; and Disseminating project goals, outcomes, monitoring outcomes and management practices in a standardized format to enable more detailed analyses. In light of growing enthusiasm surrounding the use of PES, our assessment of the current state of PES projects can help to develop effective programs by promoting the establishment of consistent reporting and potentially scientific standards for PES projects.  This study was a first step in that direction.