Us Basin

an intermontane depression in the Zapadnyi Saian, along the middle course of the Us River (a right tributary of the Enisei), in southern Krasnoiarsk Krai, RSFSR. The Us Basin is 70 km long, with a width ranging from 10 to 18 km and an elevation of 650–800 km. The basin is a plain with hilly margins. The climate is sharply continental: the average January temperature is –28.6°C, with frequent temperature inversions; the average July temperature is 16.7°C. Annual precipitation is approximately 350 mm. The growing season is 116 days. Most of the Us Basin is under cultivation, primarily with grain crops. There are areas of grassy and grassy-forb steppe on chernozems. Larch and birch forest steppes on gray forest soils and tracts of pine forest on sandy soils are found along the margins of the basin. The Us Route crosses the northeastern part of the Us Basin.