Great Lakes Depression
Encyclopedia
The Great Lakes Depression is a large semi-arid
depression
in Mongolia
that covers parts of the Uvs
, Khovd, Zavkhan and Govi-Altai aimag
s. Bounded by the Altai in the West, Khangai in the East and Tannu-Ola Mountains
in the North,
it covers the area of over 100,000 km2 with elevations from 750 to 2000m.
Small northern parts of the depression are part of Russia
.
The depression is named so because it contains six major Mongolian lakes: saline
Uvs Nuur
, Khyargas Nuur
and Dörgön Nuur; and freshwater
Khar-Us Nuur
, Khar Nuur and Airag Nuur. In addition, it includes 14,000 km2 of solonchak
s and large sand
y areas. Northern parts are dominated by arid steppes, and southern by semideserts or deserts. The major rivers are Khovd Gol, Zavkhan Gol
, and Tesiin Gol
.
The depression is a major freshwater
basin of Mongolia and contains important wetland
s of Central Asia
. The wetlands are based on the system of interconnected shallow lakes with wide reed
belts within a generally desert
steppe
. The wetlands support a number of rare and endangered
migrating birds: Eurasian Spoonbill (Platalea leucorodia), Black Stork
(Ciconia nigra),
Osprey
(Pandion haliaetus), White-tailed Eagle
(Haliaeetus albicilla), Swan Goose
(Cygnopsis cygnoides), and Bar-headed Goose
(Anser indicus). Only a few individuals of White pelican
(Pelecanus onocrotalus) remain in the Great Lakes Basin in Mongolia. They nest in catchment areas of rivers and lakes that have abundant fish and vegetation.
Semi-arid
A semi-arid climate or steppe climate describes climatic regions that receive precipitation below potential evapotranspiration, but not extremely...
depression
Depression (geology)
A depression in geology is a landform sunken or depressed below the surrounding area. Depressions may be formed by various mechanisms.Structural or tectonic related:...
in Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
that covers parts of the Uvs
Uvs Province
Uvs is one of the 21 aimags of Mongolia. It is located in the west of the country, 1336 km away from the national capital Ulaanbaatar.Its capital is Ulaangom which lies 936m above the Sea level....
, Khovd, Zavkhan and Govi-Altai aimag
Aimags of Mongolia
Mongolia is divided into 21 aimags . Each aimag is subdivided into several sums. The name aimag is derived from the Mongolian and Turkic languages word for "tribe". The modern aimags were established since 1921...
s. Bounded by the Altai in the West, Khangai in the East and Tannu-Ola Mountains
Tannu-Ola Mountains
The Tannu-Ola mountains is a mountain range in southern Siberia, in the Tuva Republic of Russia. It extends in an east-west direction and curves along the Mongolian border...
in the North,
it covers the area of over 100,000 km2 with elevations from 750 to 2000m.
Small northern parts of the depression are part of Russia
Russia
Russia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
.
The depression is named so because it contains six major Mongolian lakes: saline
Saline water
Saline water is a general term for water that contains a significant concentration of dissolved salts . The concentration is usually expressed in parts per million of salt....
Uvs Nuur
Uvs Nuur
Uvs Lake is a highly saline lake in an endorheic basin - Uvs Nuur Basin in Mongolia with a small part in Russia. It is the largest lake in Mongolia by surface area, covering 3,350 km² at 759 m above sea level....
, Khyargas Nuur
Khyargas Nuur
Khyargas Lake is a salt lake in Khyargas district, Uvs Province, Western Mongolia.Some sources are using different Khyargas Lake statistics values:*Water level: 1,035.29 m*Surface area: 1,481.1 km²*Average depth: 50.7 m*Volume: 75.2 km³....
and Dörgön Nuur; and freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
Khar-Us Nuur
Khar-Us Nuur
Khar-Us Lake is a lake in western Mongolia in the Great Lakes Depression. It is the upper one in a system of the interconnected lakes: Khar-Us, Khar, Dörgön, Airag and Khyargas....
, Khar Nuur and Airag Nuur. In addition, it includes 14,000 km2 of solonchak
Solonchak
Solonchak is pale or grey soil type found in arid to subhumid, poorly drained conditions. The word is Russian for "salt marsh" in turn from Russian sol , "salt"....
s and large sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
y areas. Northern parts are dominated by arid steppes, and southern by semideserts or deserts. The major rivers are Khovd Gol, Zavkhan Gol
Zavkhan Gol
Zavkhan River is a river in Mongolia. It flows from Khangai Mountains to Lake Khyargas. Drainage area: over 71,000 km2. The river forms most of the border between the Govi-Altai and Zavkhan aimags. The length of the river is 670 kilometres.-References:...
, and Tesiin Gol
Tesiin Gol
The Tes River is a river in northwestern Mongolia and southern Tuva, Russia. Its spring is in Tsagaan-Uul sum in Khövsgöl. The river then flows through Zavkhan , Tuva , next back to Uvs before entering Uvs Nuur lake...
.
The depression is a major freshwater
Freshwater
Fresh water is naturally occurring water on the Earth's surface in ice sheets, ice caps, glaciers, bogs, ponds, lakes, rivers and streams, and underground as groundwater in aquifers and underground streams. Fresh water is generally characterized by having low concentrations of dissolved salts and...
basin of Mongolia and contains important wetland
Wetland
A wetland is an area of land whose soil is saturated with water either permanently or seasonally. Wetlands are categorised by their characteristic vegetation, which is adapted to these unique soil conditions....
s of Central Asia
Central Asia
Central Asia is a core region of the Asian continent from the Caspian Sea in the west, China in the east, Afghanistan in the south, and Russia in the north...
. The wetlands are based on the system of interconnected shallow lakes with wide reed
Reed bed
Reed beds are natural habitats found in floodplains, waterlogged depressions andestuaries. Reed beds are part of a succession from young reed colonising open water or wet ground through a gradation of increasingly dry ground...
belts within a generally desert
Desert
A desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
steppe
Steppe
In physical geography, steppe is an ecoregion, in the montane grasslands and shrublands and temperate grasslands, savannas, and shrublands biomes, characterized by grassland plains without trees apart from those near rivers and lakes...
. The wetlands support a number of rare and endangered
Endangered species
An endangered species is a population of organisms which is at risk of becoming extinct because it is either few in numbers, or threatened by changing environmental or predation parameters...
migrating birds: Eurasian Spoonbill (Platalea leucorodia), Black Stork
Black Stork
The Black Stork Ciconia nigra is a large wading bird in the stork family Ciconiidae. It is a widespread, but rare, species that breeds in the warmer parts of Europe, predominantly in central and eastern regions. This is a shy and wary species, unlike the closely related White Stork. It is seen in...
(Ciconia nigra),
Osprey
Osprey
The Osprey , sometimes known as the sea hawk or fish eagle, is a diurnal, fish-eating bird of prey. It is a large raptor, reaching more than in length and across the wings...
(Pandion haliaetus), White-tailed Eagle
White-tailed Eagle
The White-tailed Eagle , also known as the Sea Eagle, Erne , or White-tailed Sea-eagle, is a large bird of prey in the family Accipitridae which includes other raptors such as hawks, kites, and harriers...
(Haliaeetus albicilla), Swan Goose
Swan Goose
The Swan Goose is a rare large goose with a natural breeding range in inland Mongolia, northernmost China, and southeastern Russia. It is migratory and winters mainly in central and eastern China...
(Cygnopsis cygnoides), and Bar-headed Goose
Bar-headed Goose
The Bar-headed Goose is a goose which breeds in Central Asia in colonies of thousands near mountain lakes and winters in South Asia, as far south as peninsular India. It lays three to eight eggs at a time in a ground nest....
(Anser indicus). Only a few individuals of White pelican
White Pelican
The Great White Pelican, Pelecanus onocrotalus also known as the Eastern White Pelican or White Pelican is a bird in the pelican family...
(Pelecanus onocrotalus) remain in the Great Lakes Basin in Mongolia. They nest in catchment areas of rivers and lakes that have abundant fish and vegetation.
External links
- Birdsview of the Great Lakes Depression computer visualization generated from satellite data, showing (from front to back) Dörgön Nuur, Khar Nuur, Khovd, Khyargas NuurKhyargas NuurKhyargas Lake is a salt lake in Khyargas district, Uvs Province, Western Mongolia.Some sources are using different Khyargas Lake statistics values:*Water level: 1,035.29 m*Surface area: 1,481.1 km²*Average depth: 50.7 m*Volume: 75.2 km³....
, and Uvs NuurUvs NuurUvs Lake is a highly saline lake in an endorheic basin - Uvs Nuur Basin in Mongolia with a small part in Russia. It is the largest lake in Mongolia by surface area, covering 3,350 km² at 759 m above sea level....
, as well as Üüreg NuurÜüreg NuurÜüreg Lake is a lake in western Mongolia, north-west of the Great Lakes Depression, near the western edge of the Uvs Nuur basin....
left of Uvs Nuur. The green line on the left is the valley of the Khovd Gol with Khar-Us NuurKhar-Us NuurKhar-Us Lake is a lake in western Mongolia in the Great Lakes Depression. It is the upper one in a system of the interconnected lakes: Khar-Us, Khar, Dörgön, Airag and Khyargas....
and Achit NuurAchit NuurAchit Lake is the largest freshwater lake in the Uvs Aimag of Mongolia, in the west of the country. At an elevation of 1,435 m above sea level it covers an area of 290 km². It is 28 km long, 16 km wide, and 10 m deep. The coast is covered with steppes, mostly hilly but swampy on the northwest and...
.