What is the highest basin in China?

The highest basin in China is Qaidam Basin.

Qaidam basin is a plateau basin, located in the northwest of Qinghai Province. It is a closed basin surrounded by Kunlun Mountain, Altun Mountain and Qilian Mountain, with a range of 9016 ′ e-9916 ′ e, 35 00 ′ n-39 20 ′ n, and the basin is slightly triangular, with a length of about 800 kilometers from east to west. It is one of the three inland basins in China, and it is a huge closed intermountain fault basin. Located in the northwest of Qinghai Province and the northeast of Qinghai-Tibet Plateau, mainly in Haixi Mongolian and Tibetan Autonomous Prefecture. Northwest and north reach Altun Mountain; Southwest to Kunlun Mountain; There is Qilian Mountain in the northeast, covering an area of 257,768 square kilometers. Inland is rich in iron ore, copper ore, tin ore, salt ore and other minerals, so it is called "cornucopia". Qaidam is a Mongolian language, which was compiled by the Qing rulers to clear the language barrier and consolidate the rule of the northwest frontier after pacifying the western regions, and was personally examined and approved by Emperor Qianlong. It is clearly recorded in Sixteen Volumes, an important reference book for studying the history and geography of northwest ethnic minorities: "Mongolian, Qaidam, is vast." Riverside, spacious, hence the name. " Deliberately meaning "vast", however, due to some subjective and objective reasons such as history, some people have adopted the interpretation of "salt ze". In fact, there are different opinions in academic circles.

Geographical features

Qaidam basin is a plateau basin, located in the northwest of Qinghai Province, mainly in Haixi Mongolian and Tibetan Autonomous Prefecture. It is a closed basin surrounded by Kunlun Mountain, Altun Mountain, Qilian Mountain and other mountains, with a range of 9016 ′ e-9916 ′ e, 35 00 ′ n-39 20 ′ n. The basin is slightly triangular, with an area of about 800 kilometers from east to west and 300 kilometers from north to south. It is one of the three inland basins in China.

Qaidam Basin is the highest elevation basin among the four great basin in China. Qaidam is not only a salt world (there are many salt lakes and swamps in the southeast), but also rich in oil, coal and various metal deposits, such as oil in Lenghu, coal in You Xiang and lead-zinc mine in Xitieshan. Therefore, the Qaidam Basin has the reputation of "cornucopia".

geologic structure

The basement of the basin is Precambrian crystalline metamorphic rock series. The terrain is slightly inclined from northwest to southeast, and the altitude gradually drops from 3000 meters to about 2600 meters. The landform is concentric and annular, and from the edge to the center, it is alluvial gravel fan-shaped land (Gobi), alluvial-diluvial silt plain, lacustrine silty clay plain and lacustrine silt saline soil plain in turn, and the change law is. Salt lakes and swamps are widely distributed in low-lying areas.

The ratio of the inner edge of the Gobi belt in the northwest of the basin is high, and the hills below 100 meters are clustered. The southeastern part of the basin has serious subsidence, and the alluvial area and lake plain are vast. Major lakes, such as South and North Horuson Lake and Dabson Lake, are distributed here. There are large swamps in the lower reaches of Qaidam River, Sulingole River and Golmud River and around the lake.

Due to the uplift of a series of low mountain fault blocks of metamorphic rocks in the northeast of the basin, a secondary small intermountain basin was formed between the basin and Qilian Mountain. From west to east, there are Huahaizi, Dachaidan, Delingha and Wulan basins in turn, and the rivers in these basins pour into lakes in their low-lying centers respectively.

Most rivers are intermittent, and the total number of rivers is only 100, mainly distributed in the east of the basin, and the water network in the west is extremely sparse. Most lakes in the basin have been salinized, and there are more than 20 large and small salt lakes.

climate

main feature

Qaidam basin belongs to plateau continental climate. Characterized by drought. The annual precipitation decreases from 200mm in the southeast to 15mm in the northwest, and the annual average relative humidity is 30-40%, and the lowest can be lower than 5%. The annual average temperature in the basin is below 5℃, and the temperature changes dramatically. The annual absolute temperature difference can reach above 60℃, the daily temperature difference is often around 30℃, and it can drop below 0℃ at night in summer. The wind is strong, and the number of gale days above magnitude 8 can reach 25-75 days, and there can even be a gale of 40 meters per second in the west, with strong wind erosion.

climate change

From 196 1 to 2006, the temperature in China increased by 0. 10-0.20℃ and that in Qinghai Plateau by 0.33℃ every 10. Among them, the Qaidam basin is as high as 0.44℃ per 10 year. As a result, the Qaidam basin has become the most significant warming area in Qinghai Plateau and even the whole country.

While the temperature rises, the precipitation in the Qaidam Basin continues to increase. Since 1998, the precipitation in most areas of Qaidam basin has been increasing continuously, and the increasing trend is obviously greater than that in other areas of Qinghai Province. From 1998 to 2008, the average annual precipitation in all parts of the Qaidam Basin ranged from 13.5 to 95.5 mm, and compared with the historical average, the precipitation in most areas increased by more than 10%.

The remarkable influence of global warming on the Qaidam Basin also makes it the most sensitive and significant area of climate change in the whole Qinghai-Tibet Plateau. There are various indications that the climate in Qaidam basin has changed from warm dry to warm wet.

Catastrophic weather

On 2011March 17, a disastrous dusty weather occurred in Golmud, Qaidam basin, Qinghai province from 1: 33 to 2: 28 am, with the maximum wind speed of 26.3 meters per second. This is also the sandstorm weather with the highest wind speed in the Qaidam Basin in recent 40 years, which has affected the production and life of local people.

At that time, when the dust passed, the maximum visibility was less than 1 m. After the windy and dusty weather, snowflakes floated over Golmud City. According to the meteorological department, the temperature drop in Golmud is around 8℃ due to dust and snowfall.

ecological environment

Vegetation condition

The natural landscape of Qaidam Basin is arid desert, and the main soil types are salinized desert soil and gypsum desert soil. The latter is mainly distributed in the west of the basin, and meadow soil and swamp soil are generally salinized.

Vegetation is sparse and simple, with less than 200 species, mainly shrubs, semi-shrubs and herbs with high drought resistance, and more halophytes. The vegetation structure is simple, and about 6/ 10 associations are composed of one or several species.

In the foothill alluvial fan and alluvial plain, the desert vegetation community is mainly composed of ramie, ephedra, Haloxylon ammodendron and red sand shrubs; In salt marshes, along salt lakes and rivers, Cyperaceae plants densely form grass mounds, among which the dominant halophytes are Juncus purpurea, Seriphidium sericeum and black moss. Reed and Leymus chinensis dominate the periphery of salt lakes and swamps.

Animal distribution

The fauna in Qaidam Basin is characterized by the transition from Meng Xin to Qinghai-Tibet. Wild animals mainly include wild camels, wild donkeys, wild yaks, antelopes, green sheep, marmots, wolves, Ma Xiong, roe deer, foxes and badgers. Due to reclamation and hunting, wild animals have been greatly reduced, and some are on the verge of extinction.

resource development

mineral resources

There are more than 200 proven ore occurrences with more than 50 kinds, among which salt, oil, lead, zinc and borax are particularly rich, with a total salt reserve of about 60 billion tons. Glauber's salt, potassium salt and borate have industrial development value. For example, Qarhan Potash Plant has become an important chemical raw material base in China. Oil storage structures are widely distributed in the basin, and there are important oil and gas accumulation zones in the west. Xitieshan lead-zinc mine is one of the largest known lead-zinc mines in China.

The Qaidam Basin covers an area of 250,000 square kilometers, and the potential value of various resource reserves reaches 17.2 trillion yuan. In order to attract domestic and foreign capital and build the Qaidam Basin into a resource industrial base in western China, the Haixi State Party Committee and State Government actively constructed a new economic pattern with resource economy as the main body, with GDP growth exceeding 15% for three consecutive years.

An industrial base has been built in Qaidam Basin to produce 2.5 million tons of crude oil, 6.5438 billion cubic meters of natural gas, 700,000 tons of potash fertilizer, 2 million tons of crude salt, 6.5438 million tons of soda ash and nearly 6.5438 million tons of copper, lead, zinc and asbestos.

Medicinal material resources

According to the investigation data of Tibetan medicine resources in the Qaidam Basin by the relevant departments of Haixi Mongolian and Tibetan Autonomous Prefecture, there are 782 kinds of medicinal plants, animals and minerals in the Qaidam Basin, and the Chinese and Tibetan medicines produced are not only rich in reserves, but also have good medicinal effects. For example, white-lipped deer antler is recognized as a first-class nourishing medicinal material, and Lycium barbarum planted in large quantities in the basin has been tested and analyzed by Northwest Plateau Institute of Biology of Chinese Academy of Sciences and Northwest Agricultural University, and its medicinal effective components exceed all similar medicinal materials in China.

Rhodiola is a medicinal plant distributed in this basin, which has been considered by the medical community as a new source of nutritional supplements after ginseng and acanthopanax senticosus. Studies show that Rhodiola sachalinensis is rich in amino acids and a variety of essential trace elements, which not only has the functions of anti-hypoxia, anti-cold, anti-fatigue, but also has the functions of delaying human aging, preventing and treating senile diseases, and has become an essential medicine for tourists entering Tibet.

The red wolfberry in Qaidam basin is also famous, especially for its pollution-free and organic nature. It is the largest pollution-free organic Lycium barbarum planting area in China, mainly exported to European and American markets.

The famous salt lake

Qinghai Province has salt lakes, some of which are in this basin, while Keke Salt Lake and Gahai Salt Lake are in other areas (Laangcuo in Tibet is just a salt lake).

Kaka salt lake

Chaka Salt Lake is located in the northeast of Qaidam Basin and the west of Chaka Basin. The southwest of Chaka Basin is divided by the intermountain fault basin between Elashan and Xiligou, and the northeast is separated by Nanshan and Qinghai Lake in Qinghai. The southern and northern parts of the basin are controlled by faults, forming a closed internal flow faulted basin with an area of 2400 square kilometers. Chaka stone salt mining has a long history. As early as the Western Han Dynasty, the local Qiang people had already eaten salt.

Chaerhan salt lake

If you drive along National Highway 2 15, you will find a straight road near Golmud, floating like a bridge on the Chaerhan Salt Lake. If it weren't for the four characters of "Zhang Wan Salt Bridge", you would think that this is an ordinary expressway, but in fact it is a 32-kilometer-long salt bridge, which is called "Zhang Wan Salt Bridge" because it has been transformed into a market system.

human landscape

crops

The existing cultivated land in the basin is concentrated in the oases in the east and southeast, mainly producing grain and oil, with high output per unit area.

traffic

The transportation industry has begun to take shape. The Qinghai-Tibet railway has been opened to traffic and the expressway has been connected to the internet. High-speed railways have basically run through all parts of the state. At the same time, the Gedun Railway connecting the Qinghai-Tibet Railway with Dunhuang in Gansu Province has entered the later stage of the project. It is expected that the 20 18 line will be completed and opened to traffic, and it has been completed in Qinghai. A number of emerging towns such as Golmud City, Delingha City, Lenghu Town, Dachaidan Town and Mangya Town have emerged.

Train: You can take the K9803 Express (Xining-Golmud), with hard sleeper 194.00 yuan.

All the trains entering Tibet stopped at Golmud, and some trains also stopped at Delingha.

Cars: There are shuttle buses to Xining, the provincial capital, all over Qaidam, and there are also shuttle buses to neighboring areas (Dunhuang) inside and outside the province.

Aircraft: At present, branch flights from Xi 'an to Golmud, Xining to Delingha, Xining to Dunhuang to Huatugou have been opened.

Scenery wonders

Baker beam

On a Gobi desert in Qaidam basin, there is a hill about 2 kilometers long, which is called a shell beam by the locals. The thin saline-alkali soil covering layer on the surface of the shell beam is actually a shell accumulation layer of Claphabranchia and Gastropoda with a thickness of more than 20 meters. This rare natural wonder is the largest paleontological stratum found in the inland basin of China so far.

Reed boat

Shell bundle more than 20 kilometers to the west, came to the position of reed boat. This is a piece of land to be developed, so there is no fixed name. People usually say that it is in a small lake in the northwest of the Neolithic site "Nomhongta Vintari Ha". This area is the lowest place in the Qaidam Basin. The ancient sea left little lakes and swamps, so the rivers here are extremely developed, and large and small lakes exude fragrance in the depths of Gobi.

bai longdui

Ya Dan is a Uyghur language, which means "mound and steep wall", also known as "wind erosion forest" and "sand stone forest". It is a peculiar wind erosion landform.

The "Ya Dan" landform area starts from Yiliping in the west, ends at Dezong Mahai Lake in the north, ends at Mahai in the east and ends at Ertai Jinji in the south, with an east longitude of 97 degrees 18 minutes and a north latitude of 37 degrees 59 minutes, which is about 200 square kilometers west of Dachaidan Town. Due to the geological changes of hundreds of millions of years, the exposed tertiary strata were lifted by folds and broken by faults, and under the long-term action of external forces, the residual hills and trough-shaped lowlands formed by various surface materials were eroded.

Due to the erosion of strong winds and sandstorms, the cracks in the Hanhai saline-alkali beach in the basin are getting bigger and bigger with the passage of time. The originally flat surface has developed into many irregular ridges and grooves, which extend in the direction of prevailing winds. The grooves are getting bigger and bigger, and the ridges are getting smaller and smaller. Many unconnected mounds have appeared, forming a unique spectacle on the Gobi Desert, which is the famous "Ya Dan landform".

Desert control

Qinghai province has taken various measures to speed up the pace of ecological management, and the oasis area in Qaidam basin has been expanding. According to satellite remote sensing monitoring, the degree of wind erosion and desertification in the sand area of Qaidam Basin has slowed down. In recent years, the desertification area has decreased significantly, and the land desertification area has decreased by 2.7% compared with that before 2000. With the improvement of vegetation, the number of wild animals in Qaidam basin has also increased greatly.

Since 2000, 227,000 mu of farmland has been returned to forests in Qaidam Basin, with 65,438 520,000 mu of artificial afforestation and 65,438 680,000 mu of closed hills for afforestation. The compensation area for ecological benefits of national key public welfare forests has been expanded to 8,656,600 mu.

Great basin elevation: Qaidam basin elevation? 2000m-3000m

What is the altitude of Tarim Basin? 1000m-2000m

What is the altitude of Junggar basin? 500m-1000m

What is the altitude of Sichuan Basin? 200-500 meters