Ishim Steppe

Ishim Steppe 

a plain in the southern part of Western Siberia, between the Irtysh and Tobol rivers, in Kurgan, Tiumen’, and Omsk oblasts, RSFSR, and Severnyi Kazakhstan Oblast, Kazakh SSR. The plain, which varies in altitude from 120 to 140 m, is composed chiefly of sand and clay deposits of the Neocene era, covered with loess-like loams. The terrain is characterized by a series of crests and hollows, with the ridges extending from the northeast to the southwest. In the lowlands and valleys there are many fresh, bitter, and salt lakes, including Saltaim, Ik, and Sazykul’. The smaller lakes and rivers dry up in the summer. The vegetation is chiefly of a meadow-steppe and birch forest (kolki ) type, growing on leached and normal chernozem and gray forest soils. In the south the plain is entirely under cultivation.