Uvs Lake Basin (also Uvs Nuur Basin or Ubs Nuur Basin; Mongolian: Увс нуурын хотгор, romanized: Uws nuuriin hotgor) is an endorheic basin located on the territorial border of Mongolia and Tuva, a republic of the Russian Federation. The basin is part of the Central Asian Internal Drainage Basin and is named after Uvs Lake (Uvs Nuur, Ubsu Nur), a large saline lake situated in the western part of its drainage basin, and is one of the last remnants of the mammoth steppes. Uvs Lake is a shallow lake with an area of 3,350 km2 (1,290 sq mi). Its entire basin, which includes several smaller lakes, is 70,000 km2 (27,000 sq mi).[1]
Uvs Lake Basin may also refer to Ubsunur Hollow (Russian: Убсунурская котловина, Ubsunorskaya Kotlovina), which is the western part of the drainage basin, or to over 10,000 km2 (3,900 sq mi) of protected areas covering the lake and its surroundings. The hollow forms the northern part of the Great Lakes Depression, which has a surface of over 100,000 km2 (39,000 sq mi). The hollow, and most of the drainage basin, are situated in the Khövsgöl, Zavkhan and Uvs Provinces of north-western Mongolia, and the Mongun-Tayginsky, Ovyursky, Tes-Khemsky and Erzinsky Districts of southern Tuva.
The basin is part of a combination of raised lands and hollows located throughout the Tannu-Ola and Altai mountainous regions. Here, the world's most northern desert meets the Northern Hemisphere's most southern tundra zone. An area of 10,560 km2 (4,080 sq mi), around three quarters of which lies in Mongolia, was designated Biosphere Reserve in 1997, and a partly overlapping zone of around the same size was designated UNESCO World Heritage in 2003. The Mongolian part of the lake and its immediate surroundings were further adopted as Ramsar wetland in 2004.
Ubsunur Hollow covers the western part of the Uvs Nuur drainage basin
The Tannu-Ola mountains form the northern border of Ubsunur Hollow. Tere-Khol' Lake [sv], the only freshwater lake of the basin, lies, like Uvs Lake, on the Russian-Mongolian border. The more eastern part of the Uvs Lake drainage basin extends, in the north, to the Sengilen ridge of the Sayan Mountains, and in the east, to the basin of Sangiin Dalai Lake. The southern part of the hollow is bordered by the basin of Khyargas Lake, with the Khan Khökhii mountains separating both basins of the Great Lakes Depression. More to the east, the Bulnai mountain range [sv] forms the southern border of Uvs Lake's drainage basin. West of the Uvs Lake Basin lies the endorheic basin of Üüreg Lake, bordered by the Altai Mountains. The Tsagan-Shibetu ridge [sv] separates, in part, the Uvs and Üüreg lake basins. The south-western tip of the Uvs Lake Basin covers most of the Türgen Uul [sv] range, and includes the north-eastern slopes of Harhiraa mountain [sv][2]
Archaeology
Por-Bazhyn, shortly before the 2007–2008 excavations
Archaeological searches carried out in 2007–2008 on the Por-Bazhyn ruins, which are situated on an islet in the Russian part of Tere-Khol' Lake, suggested that the enclosure was built around the middle of the second half of the 8th century, under the Uyghur Khaganate.[5]
The population density is low in the Ubsunur Hollow. It is populated almost exclusively by the nomadic Tuvan people and cattle breeders living in yurts. The lack of industry and the reliance of the inhabitants on traditional ways of life, such as nomadic pasturing, have had little impact on the landscape and have allowed the ecosystem to remain relatively free from the negative effects that human presence can impose.[4] Both the Russian[6]
and the Mongolian parts of the hollow are home to nomadicTuvan cattle herders, who live in yurts and make up virtually all of the population.
The Hollow, located on the border between Mongolia and Russia, lies at the intersection of complex ecosystems. Its area is 10,688 km2 (4,127 sq mi).[7] The terrain includes glaciers, desert, alpine tundra, sub alpine meadows, and a vast mountain taiga areas. There are also forested steppes, treeless steppes, semi-ariddeserts, and ever shifting sand dunes. It is a diversified natural habitat, producing an interaction of Euro-Siberian and Central Asian-Mongolian plant and animal life.[4]
In 1993 Russia protected the Tuvan parts of Ubsunur Hollow as the Ubsunurskaya Kotlovina State Nature Biosphere Reserve.[4][8] In 1995 Greenpeace Russia prepared its proposal to nominate Ubsunur Hollow, in conjunction with Mongolia, as World Heritage Site, describing it as "one of the largest intact watersheds in Central Asia".[3]
Ubsunur Hollow Reserve (Tuva) was awarded international Biosphere Reserve status in 1998, as a step toward protecting Southern Siberia's wilderness which contain Russia's largest intact tracts of Siberian Pine and Siberian Fir-dominated ecosystems.[9]
World Heritage Site
Ubsunur Hollow was nominated for inclusion in Russia's second World Heritage Site (the first being the Virgin Komi Forests) in 1995 as "one of the largest intact watersheds in Central Asia where up to 40,000 unexcavated burial mounds and other archaeological sites can be found from historically famous nomadic tribes such as the Scythians, the Turks and the Huns."[3] The nomination was submitted in conjunction with the Tuva Republic and Mongolia and included 75,000 square kilometres of forest and steppe and associated cultural and natural heritage. Other sites included in this first Russian listing proposal were:
