Four Types of Ecosystem Services

According to the Millennium Ecosystem Assessment  (2005), ecosystem services are the benefits people obtain from ecosystems. They state that “the human species, while buffered against environmental changes by culture and technology, is fundamentally dependent on the flow of ecosystem services.” The MEA defines four types of ecosystem services:

• Provisioning services such as food, water, timber, and fiber.  These are outputs (material or energy) from ecosystems;
• Regulating services that affect climate, floods, disease, wastes, and water quality by acting as regulators;
• Cultural services that provide recreational, aesthetic, and spiritual benefits; and
• Supporting services such as soil formation, photosynthesis, and nutrient cycling that lead to the provision of the other ecosystem services from which humans derive a direct benefit.

Figure 1.3 from the Millennium Ecosystem Assessment Ecosystems and Human Well-being: Synthesis  report "depicts the strength of linkages between commonly-encountered categories of ecosystem services and components of human well-being, and includes indications of the extent to which it is possible for socioeconomic factors to mediate the linkage. For example, the ability to purchase a substitute for a degraded ecosystem service offers a high potential for mediation. The strength of the linkages and the potential for mediation differ in different ecosystems and regions. In addition to the influence of ecosystem services on human well-being depicted here, other factors influence human well-being including other environmental factors as well as economic, social, technological and cultural factors. In turn ecosystems are affected by changes in human well-being." Source: Corvalan C, Hales S, McMichael A (2005) Ecosystems and Human Well-being: Synthesis. Millennium Ecosystem Assessment WHO, Geneva.

A good source of information on ecosystem services can be found at “The Economics of Ecosystems and Biodiversity ” website.
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