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In physical geography, a steppe (Ukrainian : степ, Ukrainian pronunciation: [step] ) 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 huge seasonal difference, fluctuation between day and night is 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.
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 community of plants and animals that have common characteristics for the environment they exist in. 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.
Temperate grasslands, savannas, and shrublands is a terrestrial habitat type 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 surface. Moreover, they are one of our planet's most productive landscapes. 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, ecoregion, of the Palearctic temperate grasslands, savannas, and shrublands biome, is a vast region of open grassland in northern Kazakhstan and adjacent portions of Russia, extending to the east of the Pontic steppe and to the west of the Emin Valley steppe, with which it forms part of the Eurasian steppe. Before the mid-nineteenth century it was called the Kirghiz steppe, 'Kirghiz' being an old name 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 ecoregion, also known as the Mongolian-Manchurian steppe, in the temperate grassland biome, is found in Mongolia, the Chinese Autonomous region of Inner Mongolia and northeastern China.
The shortgrass prairie is an ecosystem located in the Great Plains of North America. The prairie includes lands to the west as far as the eastern foothills of the Rocky Mountains and extends east as far as Nebraska and north into Saskatchewan. The prairie stretches through parts of Alberta, Wyoming, Montana, North Dakota, South Dakota, and Kansas, and passes south through the high plains of Colorado, Oklahoma, Texas, and New Mexico.
The Northern short grasslands includes parts of the Canadian provinces of Alberta and Saskatchewan, and the American Great Plains states of Montana, North Dakota, Wyoming, South Dakota and Nebraska. One of 867 terrestrial ecoregions defined by the World Wide Fund for Nature, the United States Environmental Protection Agency (EPA) further breaks this ecoregion into the Northwestern Glaciated Plains and Northwestern Great Plains.
Mediterranean forests, woodlands, and scrub is a biome defined by the World Wide Fund for Nature. The biome is generally characterized by dry summers and rainy winters, although in some areas rainfall may be uniform. Summers are typically hot in low-lying inland locations but can be cool near colder seas. Winters are typically mild to cool in low-lying locations but can be cold in inland and higher locations. All these ecoregions are highly distinctive, collectively harboring 10% of the Earth's plant species.
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affect the ecosystem because temperatures fall as elevation increases, causing the ecosystem to stratify. Dense montane forests are common at moderate elevations, due to moderate temperatures and high rainfall. At higher elevations, the climate is harsher, with lower temperatures and higher winds, preventing the growth of trees and causing the plant community to transition to montane grasslands, shrublands or alpine tundra.
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.
The Central Great Plains are a semi-arid prairie ecoregion of the central United States, part of North American Great Plains. The region runs from west-central Texas through west-central Oklahoma, central Kansas, and south-central Nebraska.
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 middle of Ukraine to the Ural Mountains in Russia. 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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