a type of soil formed under conditions of a non-leaching water regime with the accumulation of sodium (from 10 to 70 percent of the volume of absorption) in the soil absorption complex. The sodium enters from the soil solution or groundwater. The profile of a solonetz is composed of the following soil horizons: (A) the eluvial, or humus, layer (depth from 2–3 to 15–25 cm, humus content from 1–5 to 9–10 percent), (B) the illuvial, or solonetz, layer (depth 10–20 cm), (BC) the transitional layer (the accumulation of gypsum and sodium sulfate may occur in this layer), and (C) parent material. Solonetzes are basic soils and have a high content of sodium bicarbonate, especially in soda solonetzes. The soils are characterized by high viscosity, stickiness, and swelling in a wet state and by high density and hardness in the dry state. The illuvial horizon has a basaltic, prismatic, or fault-block structure, and the colloids are mobile. Several groups of solonetzes are distinguished, including chernozem solonetzes, chestnut solonetzes, meadow-chernozem solonetzes, and subtropical solonetzes. These groups are further broken down into subgroups (solonchak, typical, solodized, and residual) and genera (soda and chloride-sulfate).

Solonetzes are found in patches in steppe, semidesert, and desert zones of Africa, Asia, South America, and Australia. In the USSR they occur in the Lower Volga region, the Northern Caucasus, and Kazakhstan. In preparation for cultivation these soils are washed, treated with gypsum, deeply plowed, and treated with organic and inorganic fertilizers; grass cultivation and artificial aggregate stabilizers are also used. Solonetzes may be planted with sugarbeets, soybeans, and grains (wheat, rye, barley, and millet).