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In physical geography, a steppe is an ecoregion characterized by grassland plains without trees apart from those near rivers and lakes.Steppe biomes may include:
The prairie of North America (especially the shortgrass and mixed prairie) is an example of a steppe, though it is not usually called such. A steppe may be semi-arid or covered with grass or with shrubs or with both, depending on the season and latitude. The term "steppe climate" denotes the climate encountered in regions too dry to support a forest but not dry enough to be a desert. Steppe soils are typically of the chernozem type.
Steppes are usually characterized by a semi-arid or continental climate. Extremes can be recorded in the summer of up to 45 °C (115 °F) and in winter, −55 °C (−65 °F). Besides this major seasonal difference, fluctuations between day and night are also very great. In both the highlands of Mongolia and northern Nevada, 30 °C (85 °F) can be reached during the day with sub-freezing readings at night.
Mid-latitude steppes feature hot summers and cold winters, averaging 250–510 mm (10–20 in) of precipitation per year. Precipitation level alone does not define a steppe climate; potential evapotranspiration also plays a role in the trees origin
Steppe can be classified by climate:
It can also be classified by vegetation type, e.g. shrub-steppe and alpine-steppe.
The Eurasian Grass-Steppe of the temperate grasslands, savannas, and shrublands had a role in the spread of the horse, the wheel, and the Indo-European languages. The Indo-European expansion and diverse invasions of horse archer civilizations of the steppe eventually led to the rise of Mycenaean Greece by amalgamation of Indo-Europeans with the autochthonous pre-Greek population and also its destruction during the Dorian invasion in the Late Bronze Age collapse, followed by the demise of the Achaeans, the spread of the Sea Peoples, and eventually the rise of Archaic and ultimately Classical Greece.
The world's largest steppe region, often referred to as "the Great Steppe", is found in Eastern Europe and Central Asia, and neighbouring countries stretching from Ukraine in the west through Russia, Kazakhstan, Turkmenistan and Uzbekistan to the Altai, Koppet Dag and Tian Shan ranges in China.
The inner parts of Anatolia in Turkey, Central Anatolia and East Anatolia in particular and also some parts of Southeast Anatolia, as well as much of Armenia and Iran are largely dominated by cold steppe.
The Pannonian Plain is another steppe region in Central Europe, primarily Hungary.
Another large steppe area (prairie) is located in the central United States, western Canada and northern part of Mexico. The shortgrass prairie steppe is the westernmost part of the Great Plains region. The Columbia Plateau in Southern British Columbia, Oregon, Idaho, and Washington state, is an example of a steppe region in North America outside of the Great Plains.
In South America, cold steppe can be found in Patagonia and much of the high elevation regions east of the southern Andes.
Relatively small steppe areas can be found in the interior of the South Island of New Zealand.
In Europe, some Mediterranean areas have a steppe-like vegetation, such as central Sicily in Italy, southern Portugal, parts of Greece in the southern Athens area,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 and the Badia of the Arabian peninsula.
In Australia, "subtropical steppe" 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, the inner part of California, and much of western Texas and adjacent areas in Mexico.
A biome is a collection of organisms that have adaptations for the environment in which they exist. They can be found over a range of continents. Biomes are distinct biological communities that have formed in response to a shared physical climate. Biome is a broader term than habitat; any biome can comprise a variety of habitats.
In geography, a plain is a flat expanse of land that generally does not change much in elevation, and are primarily treeless. Plains occur as lowlands along valleys or at the base of mountains, as coastal plains, and as plateaus or uplands.
Temperate grasslands, savannas, and shrublands is a terrestrial biome defined by the World Wide Fund for Nature. The predominant vegetation in this biome consists of grass and/or shrubs. The climate is temperate and ranges from semi-arid to semi-humid. The habitat type differs from tropical grasslands in the annual temperature regime as well as the types of species found here.
The Global 200 is the list of ecoregions identified by WWF, the global conservation organization, as priorities for conservation. According to WWF, an ecoregion is defined as a "relatively large unit of land or water containing a characteristic set of natural communities that share a large majority of their species dynamics, and environmental conditions". So, for example, based on their levels of endemism, Madagascar gets multiple listings, ancient Lake Baikal gets one, and the North American Great Lakes get none.
Grasslands are areas where the vegetation is dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes, like clover, and other herbs. Grasslands occur naturally on all continents except Antarctica and are found in most ecoregions of the Earth. Furthermore, grasslands are one of the largest biomes on earth and dominate the landscape worldwide. They cover 31-43% of the Earth's land area. There are different types of grasslands: natural grasslands, semi-natural grasslands, and agricultural grasslands.
A savanna or savannah is a mixed woodland-grassland ecosystem characterised by the trees being sufficiently widely spaced so that the canopy does not close. The open canopy allows sufficient light to reach the ground to support an unbroken herbaceous layer consisting primarily of grasses.
A semi-arid climate, semi-desert climate, or steppe climate is the climate of a region that receives precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi-arid climates, depending on variables such as temperature, and they give rise to different biomes.
Rangelands are grasslands, shrublands, woodlands, wetlands, and deserts that are grazed by domestic livestock or wild animals. Types of rangelands include tallgrass and shortgrass prairies, desert grasslands and shrublands, woodlands, savannas, chaparrals, steppes, and tundras. Rangelands do not include forests lacking grazable understory vegetation, barren desert, farmland, or land covered by solid rock, concrete and/or glaciers.
The Kazakh Steppe, also called the Great Dala, is a vast region of open grassland in northern Kazakhstan and adjacent portions of Russia. It lies east of the Pontic steppe and west of the Emin Valley steppe, with which it forms part of the Eurasian steppe. The Kazakh Steppe is an ecoregion of the temperate grasslands, savannas, and shrublands biome in the Palearctic realm. Before the mid-nineteenth century it was called the Kirghiz steppe, 'Kirghiz' being an old Russian word for the Kazakhs.
The Intermountain West, or Intermountain Region, is a geographic and geological region of the Western United States. It is located between the front ranges of the Rocky Mountains on the east and the Cascade Range and Sierra Nevada on the west.
The Mongolian-Manchurian grassland, also known as the Mongolian-Manchurian steppe or Gobi-Manchurian steppe, in the temperate grassland biome, is an ecoregion in East Asia covering parts of Mongolia, the Chinese Autonomous region of Inner Mongolia, and Northeast China.
The shortgrass prairie is an ecosystem located in the Great Plains of North America. The two most dominant grasses in the shortgrass prairie are blue grama and buffalograss, the two less dominant grasses in the prairie are greasegrass and sideoats grama. The prairie was formerly maintained by grazing pressure of American bison, which is the keystone species. Due to its semiarid climate, the shortgrass prairie receives on average less precipitation than that of the tall and mixed grass prairies to the east.
A mixed-grass prairie is an ecotone located between the tallgrass prairies and shortgrass prairies. The mixed-grass prairie is richer in ecological diversity than either the tall- or shortgrass prairie. The mixed-grass prairie occurs in the central plains portion of the Great Plains, varying in width from central Texas in the United States up into southeastern Manitoba, Alberta and Saskatchewan in the northern mixed grasslands of Canada.
Biogeographic classification of India is the division of India according to biogeographic characteristics. Biogeography is the study of the distribution of species (biology), organisms, and ecosystems in geographic space and through geological time. India has a rich heritage of natural diversity. India ranks fourth in Asia and tenth in the world amongst the top 17 mega-diverse countries in the world. India harbours nearly 11% of the world’s floral diversity comprising over 17500 documented flowering plants, 6200 endemic species, 7500 medicinal plants and 246 globally threatened species in only 2.4% of world’s land area. India is also home to four biodiversity hotspots—Andaman & Nicobar Islands, Eastern Himalaya, Indo-Burma region, and the Western Ghats. Hence the importance of biogeographical study of India's natural heritage.
Vegetation classification is the process of classifying and mapping the vegetation over an area of the earth's surface. Vegetation classification is often performed by state based agencies as part of land use, resource and environmental management. Many different methods of vegetation classification have been used. In general, there has been a shift from structural classification used by forestry for the mapping of timber resources, to floristic community mapping for biodiversity management. Whereas older forestry-based schemes considered factors such as height, species and density of the woody canopy, floristic community mapping shifts the emphasis onto ecological factors such as climate, soil type and floristic associations. Classification mapping is usually now done using geographic information systems (GIS) software.
The East European forest steppe ecoregion is a patchwork of broadleaf forest stands and grasslands (steppe) that stretches 2,100 km across eastern Europe from the Ural Mountains in Ural, through Povolzhye, Central Russia to the middle of Ukraine.There are also isolated areas of similar character off the western end in eastern Romania, Moldova, and Bulgaria. The region forms a transition zone between the temperate forests to the north, and the steppe to the south. The forest-steppe is an area of Russia in which precipitation and evaporation are approximately equal. The ecoregion is in the Palearctic realm, with a Humid Continental climate. It covers 727,269 km2 (280,800 sq mi).
The Sayan intermontane steppe ecoregion is sometimes referred to as a "steppe island", being an expanse of grassland and shrubs surrounded by mountain forests in the Tyva Republic of south central Siberia, Russia. The Altai Mountains are to the west, the Sayan Mountains to the north, and the Tannu-Ola Mountains to the south. The ecoregion is in the temperate grasslands, savannas, and shrublands biome, and the Palearctic realm, with a Humid Continental climate. For much of its length, it follows the course of the upper Yenisei River. It covers 33,928 km2 (13,100 sq mi).
There are many definitions of steppes. For example, Allan (1946) provides fifty-four definitions of this term. Stamp and Clark (1979) define steppes as 'mid-latitude areas dominated by herbaceous vegetation and termed locally steppes, prairies, pampas, high veldts, downland, etc.'
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