Payments for ecosystem services: a review of definitions, the role of spatial scales, and critique

The economic conservation instrument of payments for ecosystem services (PES) enjoys an increasing popularity among scientists, politicians, and civil society organizations alike, while others raise concerns regarding the ecological effectiveness and social justice of this instrument. In this review article, we showcase the variety of existing PES definitions and systematically locate these definitions in the range between Coasean conceptualizations, which describe PES as conditional and voluntary private negotiations between ES providers and ES beneficiaries, and much broader Pigouvian PES understandings that also assign government-funded and involuntary schemes to the PES approach. It turns out that the scale at which PES operate, having so far received very little attention in the literature, as well as critique of PES must be considered in the context of the diversity of definitions to ensure the comparability between studies researching PES programs. Future research should better target linkages between global, regional, and local scales for the development of PES programs, while taking local collective governance systems for a sustainable use of resources into account more seriously.