Red Earths

Red Earths

 

(Russian, krasnozemy), a type of soil formed under broad-leaved forests in a moist subtropical climate and, partially, in tropical savannas.

Typical features of red earths are a high content of sesqui-oxides (ferric and aluminum oxides) and a very low content of bases and silica. A warm, moist climate promotes intensive processes of rock disintegration, decomposition of aluminosilicates, and loss of calcium and magnesium. Ferric oxides give red earths a bright reddish or orange color. The most typical red earths are found on gentle slopes of 8°-10° to 20°-25°; on steep slopes red earths are weakly developed, shallow, and usually strongly eroded. Strongly marked horizons of washed-out and washed-in material are usually not observed in the profile of these soils. The reaction of red earths is acid or weakly acid (pH of a water extract is 5.0-5.7). They usually have a clayey loam or clayey texture. A distinction is made between the red earths of subtropical forests and those of tropical savannas.

Red earths are widespread in the central and southeastern parts of China, in Vietnam, Japan, eastern Australia, the southeastern United States, Brazil, Uruguay, Africa, the island of Madagascar, southern France, Italy, Spain, and other European countries. In the USSR they are found on the eastern shore of the Black Sea (in the Georgian SSR) and on the southwestern coast of the Caspian Sea (Azerbaijan SSR). Tea, tobacco, grapes, and citrus fruits are among the crops grown on red earths.

M. N. SABASHVILI

References in classic literature ?
Their march this day lay among singular hills and knolls of an indurated red earth, resembling brick, about the bases of which were scattered pumice stones and cinders, the whole bearing traces of the action of fire.
Same old palm-trees; same old red earth; same old black ants!
At the distance of about thirty miles from Punta Alta, in a cliff of red earth, I found several fragments of bones, some of large size.
We looked back on it now, the slanting rays of a low sun turning the streams to threads of gold and glowing on the red earth new turned by the plough and the broad tangle of the woodlands.
He crossed to the window and exclaimed, "Lord, how good it is to think of lanes, muddy lanes, with brambles and nettles, you know, and real grass fields, and farmyards with pigs and cows, and men walking beside carts with pitchforks--there's nothing to compare with that here--look at the stony red earth, and the bright blue sea, and the glaring white houses--how tired one gets of it!
In front of the first rank, along the river, three men, plastered with bright red earth from head to foot, strutted to and fro restlessly.
I remember once, and once only, hearing something remotely hinted, by a man of many speculations, concerning the origin of the human race; and by this individual, the very word Adam (or Red Earth), which you make use of, was employed.
The main soil types of the area are broadly identified as Black Earths and Grey Clays (Vertisols) and Red Earths (Alfisols).
The Grey Clay, being inherently well structured and moderately fertile, is more resilient to cropping than the Red Earths of the area.
For soils low in clay, such as the Red Earths, good correlations between aggregation and SOM have been observed.
The detrimental impact of cropping on the inherently infertile and weakly structured Red Earth soils is severe and probably occurs soon after the soils are first cultivated.
There were declines in K of 86% on the Red Earth cultivated for 15 years and 66% on the Red Earth cultivated for [is greater than] 40 years.