steppe, temperate grassland of Eurasia, consisting of level, generally treeless plains. It extends over the lower regions of the Danube and in a broad belt over S and SE European and Central Asian Russia, stretching E to the Altai and S to the Transbaykal and Manchurian plains. The term is sometimes applied to the corresponding temperate grasslands of Hungary (Puszta), the prairies of the United States, the pampas of South America, and the high veld of South Africa; it is sometimes also applied to the semiarid regions on the fringe of the hot deserts. The steppe consists of three vegetation zones with significant differences in climate—the wooded, or forest, steppe; the tillable steppe, or prairie; and the nontillable steppe. The wooded steppe has deciduous trees and the heaviest annual rainfall, over 16 in. (41 cm). The tillable steppe has black earth and an annual rainfall of between 10 and 15 in. (25-38 cm). The nontillable steppe is a semidesert, found especially around the Caspian Sea, with an annual rainfall of less than 10 in. (25 cm). There is some grazing, and its soils are relatively fertile under irrigation. Although the tillable steppe was originally grassland used almost exclusively for grazing, it is now almost entirely under cultivation. Some of the world's most productive agricultural areas, such as Ukraine and the U.S. wheat belt, are situated on the tillable steppe.

In physical geography, a steppe (German, from степь - "a flat and arid land", степ - /stɛp/, тал - tal, дала - /dɑlɑ/), pronounced in English as /stɛp/, is a grassland plain without trees (apart from those near rivers and lakes). The prairie (especially the shortgrass prairie) can be considered a steppe. It may be semi-desert, or covered with grass or shrubs or both, depending on the season and latitude. The term is also used to denote the climate encountered in regions too dry to support a forest, but not dry enough to be a desert.

Steppe are characterized by a continental and dry climate. Peaks can be recorded in the summer of up to 40 °C and in winter -40 °C. Besides this huge difference between summer and winter, the differences between day and night are also very great. In the highlands of Mongolia, 30 °C can be reached during the day and sub-zero temperatures at night.

Also, the mid-latitude steppes can be summarized by hot summers and cold winters, averaging 250-500 mm (10-20 inches) of rain or equivalent in snowfall per year.

Two types of steppe

Two types of steppe can be recorded:

• the temperate steppe, the "true" steppe, found in continental areas of the world; it can further be divided in other subdivisions; as can be seen here
• the subtropical steppe, a similar association of plants that can be found in the driest areas with a Mediterranean-like climate; it has usually a short wet period.

Peculiar types of steppe include Shrub-steppe and Alpine-steppe.

Locations

Temperate steppe

The world's largest zone of all steppes, often referred to as "the Great Steppe", is found in southwest Russia and neighbouring countries in Central Asia, stretching from Ukraine in the west to the Ural Mountains and the Caspian Sea. To the east of the Caspian Sea, the steppes extend through Turkmenistan, Uzbekistan and Kazakhstan to the Altai, Koppet Dag and Tian Shan ranges. The vast Eurasian Steppe, as it is called, is bordered in the north, on the eastern side of the Urals, by the forested West Siberian Plain taiga, extending nearly as far as the Arctic Ocean.

Another large steppe area is located in the central United States and western Canada. The High Plains steppe is the westernmost part of the Great Plains region.

Patagonia is another land dominated by a steppe. A relatively small steppe can be found in New Zealand, in the inner part of the South Island and in Hungary (the Puszta).

Subtropical steppe

In Europe, some Mediterranean areas have a steppe-like vegetation, such as central Sicily and central-eastern Spain, especially the southeastern coast (around Murcia) and places cut off from adequate moisture due to rain shadow effects such as Zaragoza.

In Asia, a subtropical steppe can be found in semi-arid lands that fringe the Thar desert of the Indian subcontinent; in Australia it can be found in a belt surrounding the most severe deserts of the continent and around the Musgrave Ranges.

In North America this environment is typical of transition areas between zones with a Mediterranean climate and true deserts, such as Reno, Nevada and the inner part of California; In South America the most important zone with a warm steppe is the Pampa.

Tropical grasslands and shrublands similar to steppe

Other zones dominated by grasslands and shrublands similar to steppe can be found in tropical areas of the world. In these locations, necessary rainfall to separate steppes from true deserts may be half as much again due to greater evapotranspiration. These include transition zones between savanna and severe desert such as the Sahel that fringes the true Sahara.

Another significant "tropical steppe", noteworthy for not grading into desert, is the Sertão of northeastern Brazil.

Notes

References

• Ecology and Conservation of Steppe-land Birdsby Manuel B.Morales, Santi Mañosa, Jordi Camprodón, Gerard Bota. International Symposium on Ecology and Conservation of steppe-land birds. Lleida, Spain. December 2004.ISBN 84-87334-99-7

See also

External links

• The Steppes. barramedasoft corporation. Retrieved on 2008-04-04..