Brief introduction and detailed information of Mu Us Desert
The sand belt along the Great Wall in northern Shaanxi and the sand in the south of Ordos (Yikezhaomeng) in Inner Mongolia are continuously distributed in the Mu Us Desert, so the sand in the southeast of Ordos Plateau and along the Great Wall in northern Shaanxi are collectively called "Mu Us Sandy Land".
Location The Mu Us Desert is one of the four major sandy lands in China, located between Yulin area of Shaanxi Province and Erdos city of Inner Mongolia Autonomous Region, with an area of 42,200 square kilometers. It is located at 37 27.5'-39 22.5' north latitude and107 20'-130' east longitude. Including the southern Ordos of Inner Mongolia Autonomous Region, the sandstorm area in the northern Yulin City of Shaanxi Province and the northeast Yanchi County of Ningxia Hui Autonomous Region.
More precipitation is beneficial to plant growth. Originally, it was a relatively developed area of animal husbandry, with a large area of fixed and semi-fixed sand dunes. The Great Wall of Wan Li runs through the southern edge of the desert from east to west. ?
The elevation of Mu Us sandy land is mostly at1100-1300m, slightly higher in the northwest, reaching 1400- 1500m, and it can reach 1600m in some areas. The valley in the southeast is as low as 950 meters.
Mu Us Desert Landscape Atlas Mu Us desert area is mainly located in the lake alluvial plain depression between Ordos Plateau and Loess Plateau. Beams exposed at the periphery of the sand area and extending into the sand area are mainly Cretaceous red and gray sandstone, and the rock strata are basically horizontal, and most of the beams have flat top surfaces.
Various Quaternary sediments are obviously sandy, and loose sand layers are transported by the wind to form flowing quicksand. Plain high beach land (including plain watershed land and Liangbian high beach land) is mainly distributed in Holocene Pliocene lacustrine alluvium.
The annual average temperature in the climatic sand area is 6.0-8.5℃, 1 month average temperature is -9.5- 12℃, the average temperature in July is 22-24℃, and the annual precipitation is 250-440mm, which is concentrated in July-September, accounting for 60-75% of the annual precipitation, especially in August. The precipitation varies greatly from year to year, and the rainy year is 2-4 times that of the dry year. Drought and waterlogging often occur, and drought is greater than waterlogging.
Atlas of Mu Us Desert Landscape Atlas of Mu Us Desert (2) Rainstorms and hail disasters are frequent in summer, and the maximum daily precipitation can reach 100-200mm. The annual precipitation in the eastern part of the sandy land is 400-440 mm, which belongs to the shallow chestnut grassland belt. The quicksand and Bala (semi-fixed and fixed dunes) are widely distributed, and the precipitation in the northwest is 250-300 mm, which belongs to the brown calcareous semi-desert belt.
Land types and utilization of Mu Us sandy land are at the intersection of several natural zones, and vegetation and soil show transitional characteristics. Except for the semi-desert belt of brown calcareous soil in the northwest, the semi-desert belt of gray calcareous soil in Yanchi area in the southwest, and the forest grassland belt of gray cinnamon soil in the warm temperate zone of the Loess Plateau in the southeast.
The land use types in Mu Us Desert are complex, and different land use patterns are often intertwined. Farming, forestry and animal husbandry land are staggered, showing obvious regional differences from southeast to northwest. The southeast has superior natural conditions, serious man-made damage and large flow. In addition to quicksand, there are patches of semi-fixed and fixed sandy land in the northwest.
Farmland in the eastern and southern regions is highly concentrated in valley terraces and beaches, while farmland in the northwest region decreases and grassland distribution increases. The existing land for agriculture, animal husbandry and forestry has not been fully utilized and the management is extensive.
The quicksand area of the whole region 1.38 square kilometers. After the founding of New China, sand fixation, water diversion and sand pulling, irrigation development, afforestation, soil improvement and desert transformation have achieved remarkable results. Through various transformation measures, the southeast of Mu Us Sandy Land has changed.
The research on the origin and evolution history has long been a professional knowledge; Because I know how it became like this, and I know how to improve it. There are several theories about geological reasons and historical reasons, but it is generally believed that most areas of the Mu Us Desert used to be rich in water and grass in ancient times. In the 5th century, the south of Maowusu (now Beibaichengzi in Jingbian County) was once the political and economic center of Xiongnu.
At that time, the Mu Us Desert had vast grass beaches and clear rivers. According to research, in ancient times, this area was a good pasture with abundant water plants and pleasant scenery.
Later, due to unreasonable reclamation, climate change and war, the ground vegetation was completely lost, and sand was blown on the spot, forming the later desert (sand). The Mu Us Desert gradually expanded during the 1000-2000 years. Sand accumulation began in the Tang Dynasty, and a vast desert was formed in the Ming and Qing Dynasties.
The researcher's viewpoint in the evolution process is that there is a small piece of primitive desert between Eqi Banner, Etuokeqian Banner and Wushen Banner. According to textual research, the most primitive desert in Mu Us Desert is only a small piece in the west of modern sandy land.
However, because the shallow surface of the whole Ordos Plateau is composed of gravel formed in geological period, once the turf is destroyed, it becomes a desert. Therefore, after excessive nomadism in history, the desert finally spread like infectious psoriasis.
Maowusu Desert Maowusu area once developed agriculture during the pre-Qin, Qin and Han dynasties, and then it was a nomadic area until the early Tang Dynasty.
Later, after unreasonable reclamation, vegetation destruction, quicksand continued to expand. A researcher in Shaanxi believes that the destruction of forests and grasslands in Mu Us stems from overgrazing of Zhao Wu, the "Liu Huguo" in the early Tang Dynasty. By the Song Dynasty, the desertification of Mu Us had spread to the southeast, and its advancing speed was even faster from the late Ming Dynasty to the early Qing Dynasty.
The Great Wall passes through us. In the middle and late Ming dynasty, "scraping sand" for the Great Wall has always been a national event. The huge cost of scraping sand worried civil and military officials. The consequence of not scraping sand is "riding in and out, like walking on the ground;" They took my property and raped my woman. "
By the middle of the17th century, there was finally no need to scrape sand, because the Ming Dynasty was dead. The Great Wall ceased to be used in the Qing Dynasty.
By 1949, mobile sand dunes are densely distributed in Jingbian, Yulin and Shenmu of the Great Wall, but most of them are fixed and semi-fixed sand dunes in the northwest.
During the formation of Mu Us Desert, thousands of square kilometers of sandy land between Shenmu-Yulin-Wushenqi should be classified as "Xuansun". In fact, until the early Qing dynasty, there were forests and grasslands here; Today, there are still thousands-year-old natural cypress forests and Chinese pine forests in the northwest of Fugu County and Yangshita Township of Zhungeer Banner-they are the witness of the disappearance of dense forests in the eastern part of the Shaanxi-Mongolia border and the last line of defense for desert invasion to the south.
There used to be a story about "Three Major Movements in Yulin". Today is different from the past. Yulin is now a "famous border city".
Since 1959, we have made great efforts to build windbreaks, adjust water and sediment, divert flood and sediment, and carried out a vast project to transform the desert.
There are two forces in contemporary Mu Us governance: the government and the people. Examples of spontaneous sand control by people and enterprises who invest in sand control abound; * * * It is planned by Ningxia, Shaanxi and Inner Mongolia, and approved and guided by the Third North Bureau of the Ministry of Forestry. From the 1960s to the present, half a century's sand control efforts have actually achieved remarkable results on the ground, in addition to stripping away mystery and loss.
265,438+Persistent ecological management at the beginning of the 20th century made more than 6 million mu of quicksand in the Mu Us Desert "stop" and grow green. In particular, Yulin City in northern Shaanxi, which suffered from sandstorms in history, has now been built into a "frontier oasis". The quiet Yuxi River passes through the bustling urban area, and the willows on both sides are lush; Blue waves are rippling in the vast Hongjiannao Lake, and seagulls are flying by the lake.
Yulin City has built more than 165 forests with an area of 1 10,000 mu in the hinterland of the desert, and built four large-scale shelterbelts with a total length of 1500 km, with an afforestation preservation area of 1629 mu, and the forest and grass coverage rate has increased from 0.9% to 25%. More than 6 million mu of the city's 8.6 million mu of quicksand have been fixed and semi-fixed, realizing the reversal of regional desertification. The annual sandstorm weather decreased from more than 20 days in the 1960s and 1970s to less than 10 days.
Shaanxi covers the Yellow River and the Yangtze River, and ecological problems such as soil erosion, desertification and desertification are prominent. As of 2005, there are still more than 44.8 million mu of desertified land. Especially Yulin and Yan 'an in northern Shaanxi, the ecological environment is extremely fragile.
Yulin City has been hit by sandstorms from the north for a long time, and Yuyang City was forced to "expand southward" three times in history. Today, Yulin City's 6.5438+0.76 million mu of backbone forest belt, 6.5438+0.5 million mu of farmland forest net and 2.3 million mu of scattered forest land have firmly locked the yellow sand that was raging in the past.
Shaanxi province has intensified ecological management, and the forest coverage rate in the province has increased from 28.8% to 3 1%. The monitoring results of land desertification released by Shaanxi Provincial Forestry Department in June 2005 show that compared with 1999, the area of desertified land in Shaanxi Province has decreased by 189 mu, the area of desertified land has decreased by 300,000 mu, and the area of extremely severe desertification has decreased by 1952 mu.
In the 1960s, there was barren quicksand half a kilometer away from the suburb of Yulin, but from 265438 to the beginning of the 20th century, there was basically no quicksand within 50 kilometers. Many sandy lands in those days have now become woodlands, grasslands and fertile fields. In the hinterland of the desert, Yulin has also built 6.5438+0.6 million mu of farmland.
Tree planting heroes span the Mu Us Desert in Ningxia, Shaanxi and Inner Mongolia, which is the largest number of tree planting heroes in almost all desert areas in China: Baori, Wuyun Siqing, Yin, Sheng, Wang Youde, Bai Chunlan, Niu, Shi Guangyin ... From the "model workers" in the "commune" era to entrepreneurs in the self-contracted sand era, they survived one by one.
For example, Shi Guangyin of Dingbian, Yulin, spent more than 20 years planting a 6-kilometer-wide green belt on the edge of the 63-kilometer-long desert-the speed of "people entering the sand and retreating", which is equivalent to more than twice the speed at which quicksand eroded Yulin city walls during the Tongzhi period in the late Qing Dynasty.
Traffic Information Jingbian County drives along G20 National Road by car, and you can see the desert scenery along the way.