Oasis
Oasis, (plural: oases), a fertile green area in a desert where water is available. Oases may occur naturally, as at a spring or other source of water, or they may be made by the discing of wells or the diversion of water from a distant place. Oases vary from him, unpopulated areas of palm trees to extensive cultivated areas having sizable permanent populations.
Because of the isolated location of oases, inhabitants must produce much of their own food and other necessities. Crops are tended with great care, and water is used sparingly. Oasis crops often include dates, citrus fruit, vegetables, and grains. Nomadic herders sometimes use oases as temporary dwelling places.