Payment for Environmental Services (PES) - Center for International Forestry Research

What are Ecosystem Services?

The Millennium Ecosystem Assessment defines “ecosystem services” as those benefits that people obtain from ecosystems. These benefits can be direct, as in the production of provisions, such as food and water (“provisioning services”), or the regulation of features such as floods, land degradation, desiccation, soil salinization, pests and disease (“regulating services”), or indirect, through the functioning of ecosystem processes that produce the direct services (“supporting services”). Examples of supporting services would be the processes of photosynthesis and the formation and storage of organic material; nutrient cycling; soil creation; and the assimilation, neutralisation and detoxification of wastes. Ecosystems also provide people with non-material benefits such as aesthetic pleasure, recreational opportunities, and spiritual and cultural sustenance (“cultural services”). There are thus a range of ecosystem services, some of which benefit people directly, others which do so indirectly.

Obviously, changing land uses also make a different for what type of service an ecosystem will produce. Some services have the characteristics of “public goods” in that people usually cannot be excluded from benefiting from them, and the use of the service by one person does not significantly diminish the availability of that service to other users. Nevertheless, people can degrade the capacity of ecosystems to continue supplying these services, either through changing the composition and structure of a system and how it works, or through extracting material from the ecosystem at a rate that is above the replenishment capacity of the ecosystem. Paying for ecosystem services is aimed at providing land users with incentives not to degrade ecosystems and their services, but rather to protect them.

Whereas the different elements of an ecosystem, and therefore the various services that an ecosystem provides, are functionally linked, in any one instance a buyer of “ecosystem services” (more usually referred to as environmental services) is likely to be interested in the measurable, or at least verifiable benefits of a particular service, rather than the whole suite of them. The management required to provide these services will also vary, depending on the service concerned. Environmental services are therefore usually bundled into four main classes: watershed services, concerned primarily with the provision of adequate amounts of good quality water, and secondarily with hydrological control of such phenomena as flooding, erosion and soil salinization; carbon sequestration, involving the long-term storage of carbon in woody biomass and soil organic matter; biodiversity conservation, related to those processes that determine and maintain biodiversity at all levels (landscapes, species and genes); and aesthetic features or landscape beauty, the maintenance of which serve as sources of inspiration, culture and spirituality, as well as commerce in the form of eco-tourism. Those are the four service areas where actual payments have so far been made.