Қытайдың Лоп шөлі

Desert in China

The Lop Desert, or the Lop Depression, is a desert extending from Korla eastwards along the foot of the Kuruk tagh (meaning Dry Mountain) to the former terminal Tarim Basin in the Xinjiang Uyghur Autonomous Region of China. It is an almost perfectly flat expanse with no topographic relief. Lake Bosten in the northwest lies at an altitude of , while the Lop Nur in the southeast is only 250 m lower.

The Lop Desert is on the whole flat, but with three slightly more depressed areas which might form lakes if filled with water the Lop Nor dried basin, Kara Koshun dried basin and the Taitema Lake basin. These formed, at one time or another, the terminal lakes of the Tarim Konque Qarqan river system. The Tarim River changes its course through time, and therefore the location of the terminal lake also changes, causing some confusion amongst the early explorers as to the exact location of Lop Nor, and the lake was thus referred to as the "Wandering Lake." In the past Lop Nur was a huge marsh in the eastern part of Xinjiang. Now the region is a broad, unbroken expanse of clay intermingled with sand. The clay, mostly of a yellow or yellow grey color, is hard and thickly sprinkled with fine gravel. There are benches, flattened ridges and tabular masses of consolidated clay (yardangs) that are in a distinctly defined laminae, three stories being sometimes superimposed one upon the other, while their vertical faces are abraded, and often undercut, by the wind. The formations themselves are separated by parallel gullies or wind furrows, 6 to 20 feet deep, all sculptured in the direction of the prevailing northeast to southwest wind. There is no drifting sand or sand dunes, except in the south towards the outlying foothills of the Altyn Tagh.

There are numerous indications that suggest the presence of an extensive lake in this region which is now completely desiccated. These indications include salt stained depressions of a lacustrine appearance; traces of former lacustrine shorelines, more or less parallel and concentric; the presence in places of vast quantities of fresh water mollusc shells (species of Lymnaea and Planorbis); the existence of belts of dead poplars; patches of dead tamarisks and extensive beds of withered reeds, all of these are always on top of the yardangs, never in the wind etched furrows. It was also called Yan Ze (鹽澤) in Shiji, which means "salt marsh", indicating that the lake was salty. The lake had already shrunk considerably by the Qing dynasty. It had shifted its location to Kara Koshun by the latter half of the nineteenth century, then back again to Lop Nor in 1921 through human intervention. The building of dams by Chinese garrisons in the twentieth century blocked the water from the rivers feeding in to Lop Nor and it is now primarily salt flats. The dried up Lop Nor basin is covered with a salt crust from thick.

Natural vegetation is sparse in the region and poor in the number of species. A scientific expedition to the Lop Nor region in 1979 1982 collected only 36 species of plants, belonging to 13 families (mainly Chenopodiaceae and Compositae) and 26 genera. The expedition also collected only 127 species of animals (23 mammals, 91 birds, 7 reptiles, and 1 amphibian).

The whole of this region is swept bare of sand by the terrific sand storms (burans) of the spring months and the particles of wind blown sand act like a sand blast. Abrasion of the rocks forms yardangs. The desert itself is abraded, filed, eroded and carried bodily away into the network of lakes in which the Tarim River wanders. The sand also blows across the lower, constantly shifting waterways of the Tarim River and deposits itself onto gigantic dunes that choke the eastern end of the Taklamakan Desert.