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The Gobi is most notable in history as part of the great Mongol Empire, and as the location of several important cities along the Silk Road. The Gobi measures over 1600 km from southwest to northeast and 800 km from north to south. The desert is widest in the west, along the line joining the Baghrash Kol and the Lop Nor (87?-89? east). It occupies an arc of land 1,300,000 sq km in area, making it one of the largest deserts in the world. Contrary to images often associated with a desert, much of the Gobi is not sandy but is covered with bare rock. The Gobi has several alternative Chinese language|Chinese names, including sha-mo (sand desert) and han-hal (dry sea). In its broadest definition, the Gobi includes the long stretch of desert and semidesert country extending from the foot of the Pamirs, 77? east, to the Great Khingan (Da Hinggan) Mountains, 116?-118? east, on the border of Manchuria; and from the foothills of the Altai, Sayan, and Yablonoi Mountains on the north to the Kunlun Shan, Altun Shan, and Qilian Shan ranges, which form the northern edges of the Tibetan Plateau, on the south. A relatively small area on the east side of the Great Khingan range, between the upper waters of the Songhua (Sungari) and the upper waters of the Liao-ho, is also reckoned to belong to the Gobi by conventional usage. On the other hand, geographers and ecology|ecologists prefer to regard the west extremity of the Gobi region (as defined above), the basin of the Tarim in Xinjiang and the desert basin of Lop Nor and Hami as forming a separate and independent desert, called the Taklamakan. The climate of the Gobi is one of great extremes, combined with rapid changes of temperature, not only through the year but even within 24 hours (by as much as 32?C).
Even in southern Mongolia the thermometer goes down as low as -32.8?, and in Ala-shan it rises as high as 37? in July. Average winter minima are a frigid -40?C while summertime temperatures are warm to hot, highs range up to 45?C. Most of the precipitation falls during the summer. Although the southeast monsoons reach the southeast parts of the Gobi, the area throughout this region is generally characterized by extreme dryness, especially during the winter. Hence, the icy sandstorms and snowstorms of spring and early summer. The Gobi is the source of some of the most incredible fossil finds in history, including the first dinosaur eggs. These deserts and the surrounding regions sustain many animals, including black-tailed gazelles, polecat|marbled polecats, and plover|sandplovers, and are occasionally visited by snow leopards, brown bears, and wolf|wolves. The desert features a number of drought-adapted shrubs such as gray sparrow's saltwort, gray sagebrush, and low grasses such as needle grass and bridlegrass. The area is vulnerable to trampling by livestock and off-road vehicles (human impacts are greater in the eastern Gobi Desert, where rainfall is heavier and may sustain livestock). In Mongolia, grasslands have been degraded by goats, raised by nomadic herders as source of cashmere wool. Economic trends of livestock privatization and the collapse of the urban economy have caused people to return to rural lifestyles, a movement contrary to urbanization. This movement has resulted in a great increase of nomadic herder population and livestock raising. The Gobi, broadly defined, can be divided into five distinct Deserts and xeric shrublands|desert and xeric shrubland ecoregions. The Eastern Gobi desert steppe is the easternmost of the Gobi ecoregions, covering an area of 281,800 square kilometers (108,800 square miles). It extends from the Inner Mongolian Plateau in China northward into Mongolia. It includes the Yin Mountains and many low-lying areas with salt pans and small ponds. It is bounded by the Mongolian-Manchurian grassland to the north, the Yellow River Plain to the southeast, and the Alashan Plateau semi-desert to the southeast and east. The Alashan Plateau semi-desert lies west and southwest of the Eastern Gobi desert steppe. It consists of the desert basins and low mountains lying between the Gobi Altai range on the north, the Helan Mountains to the southeast, and the Qilian Mountains and northeastern portion of the Tibetan Plateau on the southwest. The Gobi Lakes Valley desert steppe ecoregion lies north of Alashan Plateau semi-desert, between the Gobi Altai range to the south and the Khangai Range to the north. The Junggar Basin semi-desert includes the desert basin lying between the Altai mountains on the north and the Tian Shan range on the south. It includes the northern portion of China's Xinjiang province and extends into the southeastern corner of Mongolia. The Alashan Plateau semi-desert lies to the east, and the Emin Valley steppe to the west, on the China-Kazakhstan border. The Tian Shan range separates the Junggar Basin semi-desert from the Taklamakan desert, which is a low, sandy desert basin surrounded by the high mountain ranges of the Tibetan Plateau to the south and the Pamirs to the west. The Taklamakan desert ecoregion includes the Desert of Lop. Eastern Gobi desert steppe Here the surface is extremely diversified, although there are no great differences in vertical elevation. Between Ulaanbaatar (48? N 107? E) and the little lake of Iren-dubasu-nor (coor dm|43|45|N|111|50|E| ) the surface is greatly eroded, and consists of broad flat depressions and basins separated by groups of flat-topped mountains of relatively low elevation (150-180 m), through which archaic rocks crop out as crags and isolated rugged masses. The floors of the depressions lie mostly between 900-1000 m above sea-level. Farther south, between Iren-dutiasu-nor and the Hwang-ho comes a region of broad tablelands alternating with flat plains, the latter ranging at altitudes of 1000-1100 m and the former at 1070-1200 m. The slopes of the plateaus are more or less steep, and are sometimes penetrated by "bays" of the lowlands. As the border-range of the Khingan is approached, the country steadily rises up to 1370 m and then to 1630 m. Here small lakes frequently fill the depressions, though the water in them is generally salt or brackish. Both here and for 320 km south of Ulaanbaatar, streams are frequent and grassgrows more or less abundantly. There is, however, through all the central parts, until the bordering mountains are reached, an utter absence of trees and shrubs. Clay and sand are the predominant formations, the watercourses, especially in the north, being frequently excavated 2-3 m deep, and in many places in the flat, dry valleys or depressions farther south beds of locss, 5-6 m thick, are exposed. West of the route from Ulaanbaatar to Kalgan the country presents approximately the same general features, except that the mountains are not so irregularly scattered in groups but have more strongly defined strikes, mostly east to west, west-north-west to east-south-east, and west-south-west to east-north-east. The altitudes too are higher, those of the lowlands ranging from 1000-1700 m, and those of the ranges from 200-500 m higher, though in a few cases they reach altitudes of 2400 m. The elevations do not, however, form continuous chains, but make up a congeries of short ridges and groups rising from a common base and intersected by a labyrinth of ravines, gullies, glens and basins. But the tablelards, built up of the horizontal red deposits of the Han-hai (Ohruchev's Gobi formation) which are characteristic of the southern parts of eastern Mongolia, are absent here or occur only in one locality, near the Shara-muren river, and are then greatly intersected by gullies or dry watercourses. Here there is, however, a great dearth of water, no streams, no lakes, no wells, arid precipitation falls but seldom. The prevailing winds blow from the west and northwest and the pall of dust overhangs the country as in the Takla Makan and the desert of Lop. Characteristic of the flora are wild garlic, Kalidium gracile, wormwood, saxaul, Nitraria schoberi, Caragana, Ephedra, saltwort and the grass Lasiagrostis splendens. This great desert country of Gobi is crossed by several trade routes, some of which have been in use for thousands of years. Among the most important are those from Kalgan on the frontier of China to Ulaanbaatar (960 km), from Suchow (in Gansu) to Hami (670 km) from Hami to Peking (2000 km), from Kwei-hwa-cheng (or Kuku-khoto) to Hami and Barkul, and from Lanzhou (in Gansu) to Hami. Ala Shan Plateau semi-desert The southwestern portion of the Gobi, known also as the Hsi-tau and the Little Gobi, fills the space between the great north loop of the Huang He or Yellow river on the east, the Edzin-gol on the west, and the Qilian Mountains and narrow rocky chain of Longshou (Ala-shan), 3200-3500 m in altitude, on the southwest. The Ordos Desert, which covers the northeastern portion of the Ordos Plateau, in the great north loop of the Huang He, is part of this ecoregion. It belongs to the middle basin of the three great depressions into which Potanin divides the Gobi as a whole. "Topographically," says Nikola? Mikha?lovitch Prjevalski|Przewalski, "it is a perfectly level plain, which in all probability once formed the bed of a huge lake or inland sea." The data upon which he bases this conclusion are the level area of the region as a whole, the hard saline clay and the sand-strewn surface, and lastly the salt lakes which occupy its lowest parts. For hundreds of km there is nothing to be seen but bare sands; in some places they continue so far without a break that the Mongols call them Tengger (i.e. sky). These vast expanses are absolutely waterless, nor do any oases relieve the unbroken stretches of yellow sand which alternate with equally vast areas of saline clay or, nearer the foot of the mountains, with barren shingle. Although on the whole a level country with a general altitude pf 1000-1500 m, this section, like most other parts of the Gobi, is crowned by a chequered network of hills and broken ranges going up 300 m higher. The vegetation is confined to a few varieties of bushes and a dozen kinds of grasses and herbs, the most conspicuous being saxaul (Haloxylon ammondendron) and Agriophyllum gobicum. The others include prickly convolvulus, field wormwood (Artemisia campestris), acacia, Inula ammophila, Sophora flavescens, Convolvulus ammanii, Peganum and Astragalus, but all dwarfed, deformed and starved. The fauna consists of little else except antelopes, the wolf, fox, hare, hedgehog, marten, numerous lizards and a few birds, e.g. the sandgrouse, lark, stonechat, sparrow, crane, Henderson's Ground Jay (Podoces hendersoni), Horned Lark (Eremophila alpestris), and Crested Lark (Galerida cristata). The only human inhabitants of Ala-shan are the Torgod Mongols. Junggar Basin semi-desert The Yulduz valley or valley of the Khaidyk-gol (43? N 83?-86? E) is enclosed by two prominent members of the Tian Shan mountain range, namely the Chol-tagh and the Kuruk-tagh ridges?, running parallel and close to one another. As they proceed eastward they diverge, sweeping back on north and south, respectively so as to leave room for the Baghrash-kol. These two ranges mark the northern and the southern edges respectively of a great swelling, which extends eastward for nearly twenty degrees of longitude. On its northern side the Chol-tagh descends steeply, and its foot is fringed by a string of deep depressions, ranging from Lukchun (130 m below sea level) to Hami (850 m above sea-level). To the south of the Kuruk-tagh lie the desert of Lop, the desert of Kum-tagh, and the valley of the Bulunzir-gol. To this great swelling, which arches up between the two border-ranges of the Chol-tagh and Kuruk-tagh, the Mongols give the name of Ghashiun-Gobi or Salt Desert. It is some 130 to 160 km across from north to south, and is traversed by a number of minor parallel ranges, ridges and chains of hills, and down its middle runs a broad stony valley, 40-80 km wide, at an elevation of 900 to 1370 m. The Chol-tagh, which reaches an average altitude of 1800 m, is absolutely sterile, and its northern foot rests upon a narrow belt of barren sand, which leads down to the depressions mentioned above. The Kuruk-tagh is the greatly disintegrated, denuded and wasted relic of a mountain range which formerly was of incomparably greater magnitude. In the west, between Baghrash-kol and the Tarim, it consists of two, possibly of three, principal ranges, which, although broken in continuity, run generally parallel to one another, and embrace between them numerous minor chains of heights. These minor ranges, together with the principal ranges, divide the region into a series of long; narrow valleys, mostly parallel to one another and to the enclosing mountain chains, which descend like terraced steps, on the one side towards the depression of Lukchun and on the other towards the desert of Lop. In many cases these latitudinal valleys are barred transversely by ridges or spurs, generally elevations en masse of the bottom of the valley. Where such elevations exist, there is generally found, on the east side of the transverse ridge, a cauldron-shaped depression, which some time or other has been the bottom of a former lake, but is now nearly a dry salt-basin. The surface configuration is in fact markedly similar to that which occurs in the inter-mount latitudinal valleys of the Kuen-lun. The hydrography of the Ghashiun-Gobi and the Kuruk-tagh is determined by these chequered arrangements of the latitudinal valleys. Most of the principal streams, instead of flowing straight down these valleys, cross them diagonally and only turn west after they have cut their way through one or more of the transverse barrier ranges. To the highest range on the great swelling Gruni-Grzhimailo gives the name of Tuge-tau, its altitude being 2700 m above the level of the sea and some 1200 m above the crown of the swelling itself. This range he considers to belong to the Choltagh system, whereas Sven Hedin would assign it to the Kuruk-tagh. This last, which is pretty certainly identical with the range of Kharateken-ula (also known as the Kyzyl-sanghir, Sinir, and Singher Mountains), that overlooks the southern shore of the Baghrash-kol, though parted from it by the drift-sand desert of Ak-bel-kum (White Pass Sands), has at first a westnorthwest to eastsoutheast strike, but it gradually curves round like a scimitar towards the eastnortheast and at the same time gradually decreases in elevation. In 91? east, while the principal range of the Kuruk-tagh system wheels to the eastnortheast, four of its subsidiary ranges terminate, or rather die away somewhat suddenly, on the brink of a long narrow depression (in which Sven Hedin sees a northeast bay of the former great Central Asian lake of Lop-nor), having over against them the ?cheloned terminals of similar subordinate ranges of the Pe-shan (Boy-san) system (see below). The Kuruk-tagh is throughout a relatively low, but almost completely barren range, being entirely destitute of animal life, save for hares, antelopes and wild camels, which frequent its few small, widely scattered oases. The vegetation, which is confined to these same relatively favoured spots, is of the scantiest and is mainly confined to bushes of saxaul (Haloxylon), Anabasis, reeds (kamish), tamarisks, poplars, and Ephedra. Desert of Kum-tagh Desert of Hami and the Pe-shan Mountains With regard to the origin of the masses of sand out of which the dunes and chains of dunes (barkhans) are built up in the several deserts of the Gobi, opinions differ. While some explorers consider them to be the product of marine, or at any rate lacustrine, denudation (the Central Asian Mediterranean), others - and this is not only the more reasonable view, but it is the view which is gaining most ground - consider that they are the products of the aerial denudation of the border ranges (e.g. Nan-shan, Karlyk-tagh, etc.), and more especially of the terribly wasted ranges and chains of hills, which, like the gaunt fragments of montane skeletal remains, lie littered all over the swelling uplands and tablelands of the Gobi, and that they have been transported by the prevailing winds to the localities in which they are now accumulated, the winds obeying similar transportation laws to the rivers and streams which carry down sediment in moister parts of the world. Potanin points out that, "there is a certain amount of regularity observable in the distribution of the sandy deserts over the vast uplands of central Asia. Two agencies are represented in the distribution of the sands, though what they really are is not quite clear; and of these two agencies one prevails in the north-west, the other in the south-east, so that the whole of Central Asia may be divided into two regions, the dividing line between them being drawn from north-east to south-west, from Ulaanbaatar via the eastern end of the Tian Shan to the city of Kashgar. North-west of this line the sandy masses are broken up into detached and disconnected areas, and are almost without exception heaped up around the lakes, and consequently in the lowest parts of the several districts in which they exist. Moreover, we find also that these sandy tracts always occur on the western or south-western shores of the lakes; this is the case with the lakes of Balkash, Ala-kul, Ebi-nor, Ayar-nor (or Telli-nor), Orku-nor, Zaisan-nor, Ulungur-nor, Ubsa-nor, Durga-nor and Kara-nor lying east of Kirghiz-nor. South-east of the line the arrangement of the sand is quite different. In that part of Asia we have three gigantic but disconnected basins. The first, lying farthest east, is embraced on the one side by the ramifications of the Kentei and Khangai Mountains and on the other by the In-shan Mountains. The second or middle division is contained between the Altai of the Gobi and the Ala-shan. The third basin, in the west, lies between the Tian Shan and the border ranges of western Tibet. The deepest parts of each of these three depressions occur near their northern borders; towards their southern boundaries they are all alike very much higher. However, the sandy deserts are not found in the low-lying tracts but occur on the higher uplands which foot the southern mountain ranges, the In-shan and the Nan-shan. Our maps show an immense expanse of sand south of the Tarim in the western basin; beginning in the neighbourhood of the city of Yarkent (Yarkand),it extends eastwards past the towns of Khotan, Kenya and Cherchen to Sa-chow. Along this stretch there is only one locality which forms an exception to the rule we have indicated, namely, the region round the lake of Lop-nor. In the middle basin the widest expanse of sand occurs between the Edzin-gol and the range of Ala-shan. On the south it extends nearly as far as a line drawn through the towns of Lian-chow, Kan-chow and Kao-tai at the foot of the Nan-shan; but on the south it does not approach anything like so far as the latitude (42? north) of the lake of Ghashiun-nor. Still farther east come the sandy deserts of Ordos, extending southeastward as far as the mountain range which separates Ordos from the (Chinese) provinces of Shan-si and Shen-si. In the eastern basin drift-sand is encountered between the district of Ude in the north (44? 30'north) and the foot of the In-shan in the south. In two regions, if not in three, the sands have overwhelmed large tracts of once cultivated country, and even buried the cities in which men formerly dwelt. These regions are the southern parts of the desert of Takla Makan (where Sven Hedin and A. Stein have discovered the ruins under the desert sands), along the north foot of the Nan-shan, and probably in part (other agencies having helped) in the north of the desert of Lop, where Sven Hedin discovered the ruins of Lou-lan and of other towns or villages. For these vast accumulations of sand are constantly in movement; though the movement is slow, it has nevertheless been calculated that in the south of the Takla Makan the sand dunes travel bodily at the rate of roughly 50 m in a year. The shape and arrangement of the individual sand dunes, and of the barkhans, generally indicate from which direction the predominant winds blow. On the windward side of the dune the slope is long and gentle, while the leeward side is steep and in outline concave like a horse shoe. The dunes vary in height from 10-100 m, and in some places mount as it were upon one another's shoulders, and in some localities it is even said that a third tier is sometimes superimposed. The Gobi had a long history of human habitation, mostly by nomadic peoples. By the early 20th century the region was under the nominal control of China, and inhabited mostly by Mongols, Uighurs, and Kazakhs. The Gobi desert as a whole was only very imperfectly known to outsiders, information being confined to the observations which individual travellers had made from their respective itineraries across the desert. Amongst the European explorers who contributed to early 20th century understanding of the Gobi, the most important were Marco Polo (1273-1275), Gerbillon (1688-1698), Ijsbrand Ides (1692-1694), Lange (1727-1728 and 1736), Fuss and Bunge (1830-1831), Fritsche (1868-1873), Pavlinov and Matusovski (1870), Ney Elias (1872-1873), N. M. Przhevalsky (1870-1872 and 1876-1877), Zosnovsky (1875), M. V. Pjevtsov (1878), G. N. Potanin (1877 and 1884-1886), Istv?n Sz?chenyi|Count Sz?chenyi and L. von Loczy (1879-1880), the brothers Grum-Grzhimailo (1889-1890), P. K. Kozlov (1893-1894 and 1899-1900), V. I. Roborovsky (1894), V. A. Obruchev (1894- 1896), Futterer and Holderer (1896), C. E. Bonin (1896 and 1899), Sven Hedin (1897 and 1900-1901), K. Bogdanovich (1898), Ladyghin (1899-1900) and Katsnakov (1899-1900).
bg:Гоби de:Gobi es:Desierto del Gobi et:Gobi he:מדבר גובי it:Deserto del Gobi ja:ゴビ砂漠 pt:Deserto de Gobi sv:Gobi?knen Category:Deserts of Asia Category:Geography of Mongolia Category:Geography of China Category:Ecoregions This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Gobi Desert".
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