Solonchak


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The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Solonchak

 

a type of soil formed usually by the salinization of soils in steppe, desert, and semidesert regions having an exudative water regime, that is, a regime in which salts rise to the upper soil layers owing to the evaporation of groundwater from the surface. The profile of solonchak soils is differentiated into poorly defined horizons. Below the surface there usually is a swollen and suberous saline horizon; farther down there is a weakly defined or residual humus horizon with streaks and patches of salts. Salinized rock or a water-bearing level occurs more deeply. Solonchaks contain a substantial amount of highly soluble salts (from 1–3 to 10–15 percent). A distinction is made between solonchaks of primary and secondary salinization. The latter form as a result of improper irrigation. There are semi-desert and sierozem solonchaks; the basis for this classification is the residual features of the soils, from which the soils were formed.

Solonchaks are found in Central Africa, Asia, Australia, and North America. In the USSR they occur in the Caspian Lowland, the Northern Crimea, Kazakhstan, and Middle Asia. In preparation for cultivation, solonchaks are desalinized by washing and by lowering the groundwater level (desalinating drainage). Any agricultural crop suitable for the particular region may be cultivated on solonchaks.

REFERENCES

Kovda, V. A. Proiskhozhdenie i rezhim zasolennykh pochv, vols. 1–2. Moscow-Leningrad, 1946–47.
Egorov, V. V. Zasolennyepochvy i ikh osvoenie. Moscow, 1954.
Bazilevich, N. I. Geokhimiia pochv sodovogo zasoleniia. Moscow, 1965.
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Among the 194 studied Solonchaks profiles, 74% are Calcic Solonchak, 10% are Gypsic Solonchak, 4% are Gypsic Calcic Solonchak, and 12% are Solonchak, which are neither Gypsic nor Calcic.
tenuiflora Tipo de suelo Cambisol, litosol, Cambisol, litosol, luvisol, regosol regosol, rendzina, solonchak y vertisol y vertisol Regimen Xerico y ustico Xerico y ustico de humedad Color Seco: cafe palido Seco: amarillo rojizo (amarillo, rosa, rojo) (cafe, rojo, rosa) gris gris Humedo: negro (gris, cafe, Humedo: amarillo (gris, amarillo) rojo cafe, rojo) amarillo Clasificacion textural Migajon arenoso, migajon Migajon arcillo-arenoso, arcilloso, migajon migajon arenoso, arcilla.
According to FAO soil classification [20], the soil type in the experimental area is solonchak with 14.6-17.5% clay, 60.2-72.5% silt, and 12.7-22.5% sand; pH is 7.6.
Respecto a su geologia superficial, en este estado se encuentran formaciones metamorficas que datan desde el Jurasico hasta depositos aluviales del Cuaternario (Anonimo, 1981), sobre los que se desarrollan distintas variantes humicas, districas, haplicas, pelicas o calcaricas de suelos como litosoles, feozem, rendzinas, regosoles, leptosoles y vertisoles, e incluso se registran en la zona costera los de categoria gleysol y solonchak (Anonimo, 1981, 1983).
Rozoph presented following experimental formula for calculating the leaching water required for Solonchak soils [9]:
Colour Texture (%) (cm) (moist) Sand Silt Clay Floodplain (PI), Gleyic Hyposalic Solonchak (sulfatic), 14[degrees] 04'27.4" N, 16[degrees] 11'17.4" W 0-1 Az 7.5Y4/1 24.5 56.7 18.8 1-4 Bjz 7.5YR5/6 25.6 37.4 37 4-23 Bjv 7.5YR4/2 17.9 34.8 47.2 23-60 Bv 10 YR 3/3 29.4 31.4 39.2 Floodplain (P2), Gleyic Hypersalic Solonchak (sulfatic), 14[degrees] 04'23.8" N, 16[degrees] 11'16.6" W 0-1 Azm 5 Y 3/1 + 22.8 45.7 31.5 5 YR 5/8 1-8 Az 2.5 Y 4/1 27.6 32.9 39.4 8-30 Cjr 2.5 YR 3/1 + 21.3 30.7 47.7 10 YR 7/6 30-60 Cr 7.5 YR 2/2 42.3 30.5 27.2 Floodplain (P3), Gleyic Hyposalic Solonchak (sulfatic), 14[degrees] 04'21.4" N, 16[degrees] 11'06.0" W, altitude 0.41 m a.s.l.
Complejo de superficies perilacustres y lagunas litorales de trampa de postbarras, poco profundas ([menor que o igual a] 1,5m) y saladas con fondos areno-fangosos, rodeadas de manglares y comunidades halofitas sobre suelos Solonchak Gleyzado y Gley Tipico.
Water plays a major role in takyr formation, just as it does in solonchak formation.