Alas ( sah, Алаас) is a shallow depression which occurs primarily in

Yakutia Sakha, officially the Republic of Sakha (Yakutia),, is the largest republic of Russia, located in the Russian Far East, along the Arctic Ocean, with a population of roughly 1 million. Sakha comprises half of the area of its governing Far Eas ...

, which is formed by subsidence of the

Arctic The Arctic ( or ) is a polar regions of Earth, polar region located at the northernmost part of Earth. The Arctic consists of the Arctic Ocean, adjacent seas, and parts of Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenla ...

permafrost Permafrost is ground that continuously remains below 0 °C (32 °F) for two or more years, located on land or under the ocean. Most common in the Northern Hemisphere, around 15% of the Northern Hemisphere or 11% of the global surface ...

owing to repeated melting and refreezing. An alas first develops as a shallow lake as melt water fills the depression. The lake eventually dries out and is replaced by grasses and other

herbaceous Herbaceous plants are vascular plants that have no persistent woody stems above ground. This broad category of plants includes many perennials, and nearly all annuals and biennials. Definitions of "herb" and "herbaceous" The fourth edition of t ...

vegetation.

Examples

An alas is different from

thermokarst Thermokarst is a type of terrain characterised by very irregular surfaces of marshy hollows and small hummocks formed as ice-rich permafrost thaws. The land surface type occurs in Arctic areas, and on a smaller scale in mountainous areas such as ...

depressions found elsewhere in the Arctic in that the lake is only temporary. Due to the aridity of Yakutia, the lake will dry up once the underlying ice has been depleted. Alases are often used for pasturage for horses as well as hay-fields. They are common in the

Central Yakutian Lowland The Central Yakutian LowlandJohn Kimble (ed.), ''Cryosols: Permafrost-Affected Soils'' or Central Yakutian Lowlands (russian: Центральноякутская равнина; sah, Саха сирин ортоку намтала), also known as ...

. The largest alas in the world is Myuryu, located in

Ust-Aldan District Ust-Aldansky District (russian: Усть-Алда́нский улу́с; sah, Уус-Алдан улууһа, ''Uus-Aldan uluuha'', ) is an administrativeConstitution of the Sakha Republic and municipalLaw #172-Z #351-III district (raion, or '' ...

.Evolution of the Alas of Central Yakutia
(in Russian) The alas also hold great cultural importance. During the festival of Ysyakh, the traditional Yakut New Year’s day celebrated in the summer, as many as 20,000 gather to an alas in the general vicinity of

Yakutsk Yakutsk (russian: Якутск, p=jɪˈkutsk; sah, Дьокуускай, translit=Djokuuskay, ) is the capital city of the Sakha Republic, Russia, located about south of the Arctic Circle. Fueled by the mining industry, Yakutsk has become one of ...

. Other minor celebrations occur at other alas across the Republic of Sakha. Once set up there, temporary Uraha ( Yakut: Ураһа), which are homes made of birch bark are constructed among other wooden idols and structures.

References

External links

* Geography of Russia Permafrost {{SakhaRepublic-geo-stub

Examples

See also

References

External links