Earth is an ecosystem (Photo: Image by Flickr.com, courtesy of woodley wonderworks)
According the United States Environmental Protection Agency (EPA), an ecosystem is defined as a place having unique physical features, encompassing air, water, and land, and habitats supporting plant and animal life. Any group of living and nonliving organisms interdependent on one another within the same community can be an ecosystem. The earth is made up of many different ecosystems.
According the United States Department of Agriculture (USDA), an agricultural ecosystem, also known as an agroecosystem, is an ecosystem that has been domesticated. Farmland communities and the living and nonliving components within them, for example energy, machinery, irrigation and pastures, are agricultural ecosystems.