Ecosystem services are the direct and indirect benefits we obtain from nature. These include:
They also include services like flood control from natural disasters such as hurricanes. Ecosystem services have been categorized in various ways to understand their purpose and the benefits and costs of their use. The Millennium Ecosystem Assessment identifies four distinct categories of ecosystem services, based on function:
While ecosystems provide benefits to other species, evaluation of ecosystem services is directed toward benefits to humans. Ecosystem services are more strictly defined for accounting purposes as those end-products of nature that contribute directly to human well-being.