Ecosystem service

Ecosystem services are the various benefits that humans derive from ecosystems. The interconnected living and non-living components of the natural environment offer benefits such as pollination of crops, clean air and water, decomposition of wastes, and flood control.

Ecosystem services are grouped into categories of services, which was popularized in the early 2000s by the Millennium Ecosystem Assessment (MA) initiative by the United Nations. How these groups are defined varies dependent on classification system. The MA groups the services into four broad categories of services. These are provisioning services, such as the production of food and water; regulating services, such as the control of climate and disease; supporting services, such as nutrient cycles and oxygen production; and cultural services, such as recreation, tourism, and spiritual gratification.

For example, estuarine and coastal ecosystems are marine ecosystems that perform the four categories of ecosystem services in several ways. Firstly, their provisioning services include marine resources and genetic resources. Secondly, their supporting services include nutrient cycling and primary production. Thirdly, their regulating services include carbon sequestration (which helps with climate change mitigation) and flood control. Lastly, their cultural services include recreation and tourism. Evaluations of ecosystem services may include assigning an economic value to them.