Tugay is a form of

riparian A riparian zone or riparian area is the interface between land and a river or stream. Riparian is also the proper nomenclature for one of the terrestrial biomes of the Earth. Plant habitats and communities along the river margins and banks ...

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

woodland A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the ''plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...

associated with

fluvial In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluviogl ...

and

floodplain A floodplain or flood plain or bottomlands is an area of land adjacent to a river which stretches from the banks of its channel to the base of the enclosing valley walls, and which experiences flooding during periods of high discharge.Goud ...

areas in arid climates. These

wetlands A wetland is a distinct ecosystem that is flooded or saturated by water, either permanently (for years or decades) or seasonally (for weeks or months). Flooding results in oxygen-free (anoxic) processes prevailing, especially in the soils. Th ...

are subject to periodic inundation, and largely dependent on floods and groundwater rather than directly from rainfall. Tugay habitats occur in

semi-arid A semi-arid climate, semi-desert climate, or steppe climate is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration, but not as low as a desert climate. There are different kinds of semi- ...

and

desert climate The desert climate or arid climate (in the Köppen climate classification ''BWh'' and ''BWk''), is a dry climate sub-type in which there is a severe excess of evaporation over precipitation. The typically bald, rocky, or sandy surfaces in desert ...

s in

central Asia Central Asia, also known as Middle Asia, is a region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes the f ...

. Because Tugay habitat is usually linear, following the courses of rivers in arid landscapes, Tugay communities often function as

wildlife corridor A wildlife corridor, habitat corridor, or green corridor is an area of habitat connecting wildlife populations separated by human activities or structures (such as roads, development, or logging). This allows an exchange of individuals between ...

s. They have disappeared or become fragmented over much of their former range.

Distribution

The centre of the range of Tugay vegetation is the

Tarim Basin The Tarim Basin is an endorheic basin in Northwest China occupying an area of about and one of the largest basins in Northwest China.Chen, Yaning, et al. "Regional climate change and its effects on river runoff in the Tarim Basin, China." Hydr ...

in north-western

China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's List of countries and dependencies by population, most populous country, with a Population of China, population exceeding 1.4 billion, slig ...

, where the Tarim Huyanglin nature reserve in the middle reaches of the

Tarim River The Tarim River ( zh, p=Tǎlǐmù Hé, c=塔里木河; ug, تارىم دەرياسى, Tarim deryasi), known in Sanskrit as the Śītā, is an endorheic river in Xinjiang, China. It is the principal river of the Tarim Basin, a desert region ...

holds the largest areas of intact Tugay forests, with a 1993 estimate of about 61% of the total. The

Central Asia Central Asia, also known as Middle Asia, is a region of Asia that stretches from the Caspian Sea in the west to western China and Mongolia in the east, and from Afghanistan and Iran in the south to Russia in the north. It includes the f ...

n countries hold another 31%, with smaller areas remaining in the

Middle East The Middle East ( ar, الشرق الأوسط, ISO 233: ) is a geopolitical region commonly encompassing Arabia (including the Arabian Peninsula and Bahrain), Asia Minor (Asian part of Turkey except Hatay Province), East Thrace (Europ ...

and

Pakistan Pakistan ( ur, ), officially the Islamic Republic of Pakistan ( ur, , label=none), is a country in South Asia. It is the world's fifth-most populous country, with a population of almost 243 million people, and has the world's second-la ...

. Tugais also occur in the

Caucasus The Caucasus () or Caucasia (), is a region between the Black Sea and the Caspian Sea, mainly comprising Armenia, Azerbaijan, Georgia, and parts of Southern Russia. The Caucasus Mountains, including the Greater Caucasus range, have historicall ...

Vegetation

Close to rivers and where

groundwater Groundwater is the water present beneath Earth's surface in rock and soil pore spaces and in the fractures of rock formations. About 30 percent of all readily available freshwater in the world is groundwater. A unit of rock or an unconsolid ...

levels are shallow, the vegetation is usually dominated by poplars (especially ''

Populus euphratica ''Populus euphratica'', commonly known as the Euphrates poplar, desert poplar, diversiform-leaved poplar, or poplar diversifolia, is a species of poplar tree in the willow family. Description The Euphrates poplar is a medium-sized deciduous ...

'') and

willow Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...

s such as ''

Salix Willows, also called sallows and osiers, from the genus ''Salix'', comprise around 400 speciesMabberley, D.J. 1997. The Plant Book, Cambridge University Press #2: Cambridge. of typically deciduous trees and shrubs, found primarily on moist s ...

songarica''. Where the forest has been disturbed, other species such as tamarisk, sea-buckthorn and

oleaster , signifying a plant like an olive, but less valuable (cf. poetaster), may be applied to: *Feral olive trees that have been allowed to run wild *''Olea oleaster'', the wild olive *Various species of ''Elaeagnus'', notably ''Elaeagnus angustifolia'' ...

will grow. Herbaceous plants include reeds, common spike rush, jointleaf rush, fleabane,

cocklebur ''Xanthium'' (cocklebur) is a genus of flowering plants in the tribe Heliantheae within the family Asteraceae, native to the Americas and eastern Asia and some parts of south Asia . Description Cockleburs are coarse, herbaceous annual plants g ...

and thorn apple. Grass tugai vegetation is dominated by ''

Phragmites australis ''Phragmites australis'', known as the common reed, is a species of plant. It is a broadly distributed wetland grass that can grow up to tall. Description ''Phragmites australis'' commonly forms extensive stands (known as reed beds), which may ...

'', ''

Calamagrostis ''Calamagrostis'' (reed grass or smallweed) is a genus of flowering plants in the grass family Poaceae, with about 260 species that occur mainly in temperate regions of the globe. Towards equatorial latitudes, species of ''Calamagrostis'' general ...

'' and ''

Typha ''Typha'' is a genus of about 30 species of monocotyledonous flowering plants in the family Typhaceae. These plants have a variety of common names, in British English as bulrush or reedmace, in American English as reed, cattail, or punks, in ...

''. Where the groundwater is deeper, oaks and elms will dominate.British Petroleum. 2002. "Ecological Baseline Report". BTC Pipeline ESIA, Azerbaijan. Retrieved 2013-03-30. The principal causes for the loss of tugai vegetation include dam construction, tree cutting, grazing, and agriculture.

Notes

References

{{reflist Forests Deserts and xeric shrublands Riparian zone Wetlands

Distribution

Vegetation

Notes

See also

References