a lowland in Southwest Asia, mainly in Iraq but also in Iran and Kuwait. It lies in the lower regions of the Tigris, Euphrates, and Karun basins and occupies a submontane foredeep filled with sandy-argillaceous alluvial river deposits, ocean sediments from the Persian Gulf, and material from submontane slope erosion (gravel and rock debris). Most of the lowland consists of flat plains up to 100 m in elevation, reaching 200 m along the margins.
The lowland has a subtropical climate in the north and a tropical and desert climate in the south. In Basra the temperature averages 11 °C in January and 34°C in August, sometimes climbing to 50°C. Annual precipitation ranges from 100 to 200 mm. The main rivers, the Tigris and Euphrates, have high water in spring and low water in summer. They are used mainly for irrigation and transportation. The lowland supports subtropical and tropical desert vegetation, with semidesert vegetation along the edges. Gallery forests of Euphrates poplars, willows, and other trees grow in places along rivers. The principal economic activities are nomadic herding, irrigated farming, and the cultivation of date palms. Baghdad, Basra (Iraq), and Abadan (Iran) are located in the lowland.
IU. K. EFREMOV