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83-410: This desert is home to some of the tallest stationary dunes on Earth, with some reaching a height of more than 500 meters (1,600 ft; 0.31 mi), although most average at around 200 meters (660 ft). Its tallest dune is also measured, from base to peak, as the world's third tallest dune and highest stationary dune in the world. The desert also features over 100 spring-fed lakes that lie between

166-556: A hypersaline lake forming a salt crust around the rim of the lake. Although their true sources are still debated it is believed that they are being maintained by underground water streams. Most arid deserts in China are surrounded by mountains that provide water sources, and this is the case with the Badain Jaran Desert. Runoff from the mountains is then collected through gravel deposits and this allows them to run through

249-662: A 25% increase in global annual dust emissions between the late nineteenth century to present day. The increase of desertification has also increased the amount of loose sand and dust that the wind can pick up ultimately resulting in a storm. For example, dust storms in the Middle East “are becoming more frequent and intense in recent years” because “long-term reductions in rainfall [cause] lower soil moisture and vegetative cover ”. Dust storms can contribute to certain respiratory disorders such as pneumonia, skin irritations, asthma and many more. They can pollute open water, reduce

332-419: A major role in determining the biological composition of the soil , studies have shown that, in many environments, the rate of erosion and runoff decreases exponentially with increased vegetation cover. Unprotected, dry soil surfaces blow away with the wind or are washed away by flash floods, leaving infertile lower soil layers that bake in the sun and become an unproductive hardpan. Early studies argued one of

415-416: A major role in determining the biological composition of the soil , studies have shown that, in many environments, the rate of erosion and runoff decreases exponentially with increased vegetation cover. Unprotected, dry soil surfaces blow away with the wind or are washed away by flash floods, leaving infertile lower soil layers that bake in the sun and become an unproductive hardpan. This spread of arid areas

498-485: A mixture of solid bedrock and loose gravel. Several small lakes and oases scatter the desert around which limited vegetation is able to grow. The Badain Jaran Desert is well known for its numerous scattered and colorful lakes. Containing more than 140 lakes they are mainly found in the southern region in the desert. These lakes can easily be found in the larger valleys between large dunes. They are believed to provide

581-437: A probable increase from 14 million in 2010 to nearly 200 million by 2050. This presents a future crisis for the region, as neighboring nations do not always have the ability to support large populations of refugees. In Mongolia , the land is 90% fragile dry land, which causes many herders to migrate to the city for work. With very limited resources, the herders that stay on the dry land graze very carefully in order to preserve

664-498: A result, changing ocean temperature and reductions in sulfate emissions have caused a re-greening of the region. This has led some scholars to argue that agriculture-induced vegetation loss is a minor factor in desertification. Human population dynamics have a considerable impact on overgrazing, over-farming and deforestation, as previously acceptable techniques have become unsustainable. There are multiple reasons farmers use intensive farming as opposed to extensive farming but

747-468: A sand jeep at the tourist centers located along the S317 highway. Visitors can also choose to hire a driver for a daily fee. The vehicles available for tourists are 4X4 military jeeps with reinforced frames and deflated tires. These jeeps are able to drive through the desert, ascend and descend sand dunes. They remain operational for many hours. These trips by land include several stops at lakes, scenic spots and

830-464: A wide north-west bend of the river. The high population (940 in/km in 2015) and croplands density implies a high water demand , estimated at 2,400,000 m (85,000,000 cu ft)/year in the 2001–2012 time frame. This demand is mainly satisfied using the river (71%) and groundwater (29%). Notwithstanding the water influx from the rivers descending from the north-west side of the Qilian mountains,

913-455: Is a lack of political will, and lack of funding to support land reclamation and anti-desertification programs. Desertification is recognized as a major threat to biodiversity . Some countries have developed biodiversity action plans to counter its effects, particularly in relation to the protection of endangered flora and fauna . Techniques focus on two aspects: provisioning of water, and fixation and hyper-fertilizing soil. Fixating

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996-599: Is a major river system of northern China. It flows approximately 630 kilometres (390 mi) from its headwaters on the northern Gansu side of the Qilian Mountains north-northeast into the endorheic Ejin Basin in the Gobi Desert . The river forms one of the largest inland deltas or alluvial fans in the world. Its drainage basin covers about 78,600 square kilometres (30,300 sq mi) in parts of

1079-430: Is a type of gradual land degradation of fertile land into arid desert due to a combination of natural processes and human activities. The immediate cause of desertification is the loss of most vegetation. This is driven by a number of factors, alone or in combination, such as drought, climatic shifts, tillage for agriculture, overgrazing and deforestation for fuel or construction materials. Though vegetation plays

1162-512: Is a well-preserved Tibetan-Buddhist temple located in the middle of the desert. It was built in 1868 at the side of a lake. Its isolation allowed it to survive untouched and safe from the Cultural Revolution . The fine state of preservation allows visitors to explore the temples attractions including statues, wood carvings, artifacts and a small white pagoda. The temple is only accessible by land. Visitors normally reach it by renting

1245-420: Is caused by a variety of factors, such as overexploitation of soil as a result of human activity and the effects of climate change . At least 90% of the inhabitants of drylands live in developing countries , where they also suffer from poor economic and social conditions. This situation is exacerbated by land degradation because of the reduction in productivity, the precariousness of living conditions and

1328-484: Is extracted from the aquifers, increasing the water deficit; finally, in the downstream area the positive effects of the water replenishment programme of the Chinese government are visible in the increase of the stored water volume in the 2001–2012 period. Along the river course a series of stream gauges are located. For each, the following table states position and average of the (yearly cumulated) discharge. Following

1411-458: Is mostly due to the climate conditions before the growing season, which influence the rate of evapotranspiration and subsequent plant growth. The expansion of the Gobi is attributed mostly to human activities, locally driven by deforestation , overgrazing , and depletion of water resources, as well as to climate change . South America is another area vulnerable by desertification, as 25% of

1494-470: Is no single metric which can define all aspects. However, more intense climate change is still expected to increase the current extent of drylands on the Earth's continents: from 38% in late 20th century to 50% or 56% by the end of the century, under the "moderate" and high-warming Representative Concentration Pathways 4.5 and 8.5. Most of the expansion will be seen over regions such as "southwest North America,

1577-455: Is one of the few places where the singing sand phenomenon occurs, in which the sand emits a sharp, loud noise that can be maintained for more than a minute. Although it is not fully understood, it is believed that it is caused by an electrostatic charge that is generated as wind pulls the top layers of sand down a dune slope. This will produce a low pitched rumble that can reach over 105 decibels. The "singing" starts with an avalanche of sand down

1660-450: Is only shared by around 35 other beaches and deserts around the world. Under the same circumstances, it is also possible to generate another acoustic phenomenon. Moving a hand gently through the dry sand of a "booming sand dune" will shear the upper layer of sand off the slope and generate a burping sound emission (pulse-like, short bursts of sound). The Badain Jaran Desert is made up of hundreds of dunes ranging from small to large. Most of

1743-562: Is still considered to be at risk of disappearing entirely. To limit desertification, the Great Green Wall (Africa) initiative was started in 2007 involving the planting of vegetation along a stretch of 7,775 km, 15 km wide, involving 22 countries to 2030. The purpose of this mammoth planting initiative is to enhance retention of water in the ground following the seasonal rainfall, thus promoting land rehabilitation and future agriculture. Senegal has already contributed to

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1826-453: Is through the use of nitrogen-rich fertilizer. Due to the higher cost of this fertilizer, many smallholder farmers are reluctant to use it, especially in areas where subsistence farming is common. Several nations, including India, Zambia, and Malawi have responded to this by implementing subsidies to help encourage adoption of this technique. Some research centres (such as Bel-Air Research Center IRD/ISRA/UCAD) are also experimenting with

1909-411: Is useful is contour trenching . This involves the digging of 150 m long, 1 m deep trenches in the soil. The trenches are made parallel to the height lines of the landscape, preventing the water from flowing within the trenches and causing erosion. Stone walls are placed around the trenches to prevent the trenches from closing up again. This method was invented by Peter Westerveld. Enriching of

1992-467: The Bilutu Peak . Bilutu Peak (必鲁图峰) is also a location which is commonly accessed using the sandjeeps. It is the world's highest stationary dune rising 450 meters (1,480 ft) over the surrounding area, and peaking at 1,611 meters (5,285 ft) above sea level. The surrounding dunes only reach about 200 meters (660 ft). Although the biggest, it is one of several large stationary dunes within

2075-508: The Juyan Lake Basin . The delta is made of the alluvial fan of the river itself, crossed by hundreds of dry channels entrenched by the river during its frequent course changes. Because the climate of the area has followed a drying trend over the past 10,000 years or so, the delta is no longer considered active (i.e. deposits are not being built up significantly) and is slowly being eroded by wind and water action. The analysis of

2158-899: The North African climate cycle that alters the path of the North African Monsoon , caused by an approximately 40,000-year cycle in which the axial tilt of the earth changes between 22° and 24.5°). Some statistics have shown that, since 1900, the Sahara has expanded by 250 km to the south over a stretch of land from west to east 6,000 km long. Lake Chad , located in the Sahel region, has undergone desiccation due to water withdrawal for irrigation and decrease in rainfall. The lake has shrunk by over 90% since 1987, displacing millions of inhabitants. Recent efforts have managed to make some progress toward its restoration, but it

2241-575: The Yellow River , which lies farther east but flows for a significant distance in the same direction paralleling the Ruo River. The former Tangut city of Khara-Khoto , now deserted, lies near the lower end of the river. According to legend, the city was abandoned after Ming forces diverted the river away from the city in 1372. European explorers that visited the area include Pyotr Kuzmich Kozlov (1907–1909) and John DeFrancis (1935). In

2324-536: The megadunes in the desert average about 400 meters (1,300 ft) from the base while the rest average around 200 meters (660 ft). Out of all the megadunes, the Bilutu Peak (" bì lǔ tú fēng ", 必鲁图峰) is the most famous. It towers at 500 meters (1,600 ft) from the base and is the tallest dune in Asia, (third tallest in the world). Unlike most of the smaller dunes the Bilutu Peak is stationary which makes it

2407-400: The precipitation fallen annually over the basin is concentrated in this area, creating two main river courses that join just north of the hydrometric station of Yingluo. The midstream area is characterized by the presence of wide ranges of cultivated fields, mainly in the oases that follow the principal route of the river. The city of Zhangye , main centre of the region, is located next to

2490-542: The 20th century, China's main spaceport, the Jiuquan Satellite Launch Center was constructed in the lower course of the Ruo Shui, with launch pads on both sides of the river. The basin subdivision reflects the different hydrological dynamics typical of the numerous natural contexts to be found within the basin. Most of the population is found in the midstream area, together with the oases and

2573-786: The Badain Jaran Desert covers a significant part of the south-central part of the Inner Mongolia Autonomous Region as well as the North part of Gansu province. Located in the Alxa Plateau at about 1,200 meters (3,900 ft) above sea level it is listed as a subsection to the Gobi Desert . It is bound to the north by the Gobi and to the East by Mount Lang which separates it from the Ulan Buh Desert (Pinyin: wū lán bù hé shā mò Chinese: 乌兰布和沙漠) Although most of

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2656-547: The Badain Jaran Desert. Upon reaching the top there will be a clear view of the surrounding dunes as well as several colorful lakes. Also known as the ancient black city, it is located in the northwestern side of the desert near the Ruo Shui River and is located fairly close to the new city of Ejin. The ancient city was a Tangut city founded in 1032 which became the center of the Tangut empire. When Genghis Khan conquered

2739-535: The Chinese provinces of Gansu and Inner Mongolia , which flows within the Zhangye area of Gansu; when it flows across Jiuquan area, it was renamed as Ruo Shui; when it flows across Alxa League , it is called Ejin River. About 2,000 years ago, the river was said to have a much more abundant flow than it does today and thus its perennial reaches stretched much farther out into the desert than it does today. Parts of

2822-611: The Communist Chinese government. Relatives of the dead are only permitted during the time of Qingming . In November 2013, a memorial dedicated to the dead was quickly destroyed by the local government. Many graves and human remains were also removed since then to prevent people from visiting. Ruo Shui Ejin River ( Chinese : 额济纳河 ), also Etsin Gol , Ruo Shui ( Chinese : 弱水 ; lit. 'weak water', 'weak river') or Ruo He in ancient times,

2905-488: The Earth. Such variations influence the strength of the West African Monsoon, inducing feedback in vegetation and dust emission that amplify the cycle of wet and dry Sahara climate. There is also a suggestion the transition of the Sahara from savanna to desert during the mid- Holocene was partially due to overgrazing by the cattle of the local population. Research into desertification is complex, and there

2988-643: The Gobi Desert itself is still a distance away from Beijing , reports from field studies state there are large sand dunes forming only 70 km (43.5 mi) outside the city. In Mongolia , around 90% of grassland is considered vulnerable to desertification by the UN. An estimated 13% of desertification in Mongolia is caused by natural factors; the rest is due to human influence particularly overgrazing and increased erosion of soils in cultivated areas. During

3071-404: The Mongolia government has listed forest fires , blights , unsustainable forestry and mining activities as leading causes of desertification in the country. The transition from sheep to goat farming in order to meet export demands for cashmere wool has caused degradation of grazing lands. Compared to sheep, goats do more damage to grazing lands by eating roots and flowers. To mitigate

3154-422: The agricultural consortia. The main course of the river starts in the Qilian mountains at an elevation of 3650 m asl . The loamy sediment load gives the waters a dark colour which, during time, has contributed to the river being described as Hei (黑), that is Black . The orography in this part is obviously quite steep, with elevation peaks up to 5544 m asl and vegetation mainly made up of wild shrubs. Most of

3237-400: The aridity of the surrounding terrain provided an easy route for Huns and Mongols to launch raids. Since then, the river valley has been intensely cultivated and logged. However, clearing of the landscape has caused increased erosion, leading to desertification of the region and a gradual reduction of the river flow. The lower part of the river was once confused to be the middle reach of

3320-469: The available discharge data, a flow increase is present in the upstream area (up until Yingluoxia), followed by gradually decreasing values in the midstream area. This flow weakening is the result of the net balance between the tributaries descending from the north-east side of the Qilian Shan and the considerable derivations related to the cropfield area. Desertification Desertification

3403-412: The best time to visit is between June and October. Since the Badain Jaran Desert falls under temperate arid and extremely arid climatic zones, it is important to be prepared when traveling through the dunes. The average annual rainfall is only between 50 and 60mm and is mainly centered between June and August; however, the evaporation of precipitation is between 40 and 80 times than that of rainfall. Besides

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3486-622: The camp was used for " re-education through labor " to imprison intellectuals and former government officials that were declared to be "rightist" in the Anti-Rightist Movement of the Communist Party . Out of 3,000 prisoners, 2,500 died between 1957 and 1960, during the height of the Great Chinese Famine . The remains of the camp and the unmarked graveyards were poorly maintained and are heavily guarded by

3569-493: The city it flourished again under Mongol rule. However, the city fell to Chinese armies in 1372 during the Ming dynasty and was left abandoned and in ruins. It has been untouched since. Although not accessible using the same jeeps, it is possible to find transport in the city of Ejin. The infamous Jiabiangou Labor Camp was located on the edge of the desert and 27 kilometers (17 mi) from Jiuquan , Gansu . Between 1957 and 1961,

3652-644: The compound transverse megadune area. Their maximum depth reaches around 15 meters (49 ft) and attain a maximum size of around 1.5 square kilometers (0.58 sq mi; 370 acres). The lake water can be extremely saline. The shallow lakes in the southeastern region of the desert tend to have low salt concentration, averaging at less than 20 grams per liter (0.67 oz/U.S. qt; 0.80 oz/imp qt). Other lakes can show higher salt concentrations going up to more than 330 grams per liter (11 oz/U.S. qt; 13 oz/imp qt). The Badain Jaran megadunes

3735-462: The desert, providing water sources for the scattered oases. Within the desert there can be two main types of lakes found regarding their morphometry . The largely elongated shallow lakes mainly appear in the megadune area in the southeastern margin of the desert. Their depth often reaches less than 2 meters (6 ft 7 in) and only measure about .2 square kilometers (0.077 sq mi; 49 acres). The oval-shaped, deep lakes can also be found in

3818-681: The development of deserts has occurred naturally over long intervals of time. The modern study of desertification emerged from the study of the 1980s drought in the Sahel . Desertification is a gradual process of increased soil aridity . Desertification has been defined in the text of the United Nations Convention to Combat Desertification (UNCCD) as "land degradation in arid, semi-arid and dry sub-humid regions resulting from various factors, including climatic variations and human activities." Definition of Desert – That area of

3901-562: The different components of the hydrological balance in the three main areas of the basin allows to distinguish the different geoclimatic mechanisms at work. The hydrological balance, in its most complete version and formulate for a generic sub-basin, is structured as follows: Δ W = P + R i n + G i n − E T − R o u t − G o u t {\displaystyle \Delta W=P+R_{in}+G_{in}-ET-R_{out}-G_{out}} . Most of

3984-669: The difficulty of access to resources and opportunities. Geographic areas most affected are located in Africa ( Sahel region), Asia ( Gobi Desert and Mongolia ) and parts of South America . Drylands occupy approximately 40–41% of Earth's land area and are home to more than 2 billion people. Effects of desertification include sand and dust storms , food insecurity , and poverty . Methods of mitigating or reversing desertification include improving soil quality , greening deserts , managing grazing , and tree-planting ( reforestation and afforestation ). Throughout geological history,

4067-473: The dunes also contribute to maintain their fixed state. This rigid structure also allows peaks, cliffs, gullies and even caves to form as a result of water erosion and desertification . The Badain Jaran Desert, like the Tengger Desert which lies to the east (and with which the Badain Jaran Desert is currently merging due to extensive desertification) is about one-half barren, sandy desert and one-half

4150-406: The dunes in the desert are not stationary, the larger ones usually ranging above 200 meters (660 ft) are static. With these dunes only the shallow surface of the sand is constantly shifting. The middle and lower layers of the highest dunes have been compacted for more than 20,000 years causing the sand particles to harden resulting in solid layers of sand and sandstone. High moisture levels inside

4233-501: The dunes, some of which are fresh water while others are extremely saline. These lakes give the desert its name which is Mongolian for "mysterious lakes". These lakes are not completely studied and high pH lakes harbor extremely interesting animal communities. It is also crossed by one river, the Ruo Shui ("weak water"), which has formed an alluvial plain in the desert. Measuring over 49,000 square kilometers (19,000 sq mi),

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4316-470: The earth where the sum of rain and snowfall is much less than other areas, where the annual average rainfall is less than 25CM. Definition by UNO (1995) – Land degradation in barren, humid and sub-humid areas due to climate change and human activities is called desertification. As of 2005, considerable controversy existed over the proper definition of the term desertification with more than 100 formal definitions in existence. The most widely accepted of these

4399-411: The effectiveness of clean energy efforts, and halt most forms of transportation. Dust and sand storms can have a negative effect on the climate which can make desertification worse. Dust particles in the air scatter incoming radiation from the sun (Hassan, 2012). The dust can provide momentary coverage for the ground temperature but the atmospheric temperature will increase. This can disform and shorten

4482-521: The fact that it is much colder, winter and spring have very strong winds coming mainly from the northwest getting to more than 60 days long. These winds can even get up to wind force 8. Due to these aspects of the desert climate, the popular tourist time is based upon when the climate is most comfortable. Appropriate footwear should be worn due to the fact that sand temperatures can exceed 80 °C. The Badain Jaran Temple (bā dān jí lín miào 巴丹吉林庙)

4565-709: The financial impact of desertification in Inner Mongolia , Bai Jingying teaches women how to do traditional embroidery, which they then sell to provide additional income. The Gobi Desert is expanding through desertification, most rapidly on the southern edge into China, which is seeing 3,600 km (1,390 sq mi) of grassland overtaken every year. Dust storms increased in frequency between 1996 and 2016, causing further damage to China's agriculture economy. However, in some areas desertification has been slowed or reversed. The northern and eastern boundaries between desert and grassland are constantly changing. This

4648-490: The gradual and rapid ecosystem changes caused by land use. The study found that, between 1982 and 2015, 6% of the world's drylands underwent desertification driven by unsustainable land use practices compounded by anthropogenic climate change. Despite an average global greening , anthropogenic climate change has degraded 12.6% (5.43 million km ) of drylands, contributing to desertification and affecting 213 million people, 93% of who live in developing economies . There has been

4731-619: The inhabitants of drylands live in developing countries , where they also suffer from poor economic and social conditions. This situation is exacerbated by land degradation because of the reduction in productivity, the precariousness of living conditions and the difficulty of access to resources and opportunities. Many underdeveloped countries are affected by overgrazing, land exhaustion and overdrafting of groundwater due to pressures to exploit marginal drylands for farming. Decision-makers are understandably averse to invest in arid zones with low potential. This absence of investment contributes to

4814-451: The inoculation of tree species with mycorrhiza in arid zones. The mycorrhiza are basically fungi attaching themselves to the roots of the plants. They hereby create a symbiotic relation with the trees, increasing the surface area of the tree's roots greatly (allowing the tree to gather much more nutrient from the soil). The bioengineering of soil microbes, particularly photosynthesizers, has also been suggested and theoretically modeled as

4897-728: The land is classified as drylands and over 68% of the land area has undergone soil erosion as a result of deforestation and overgrazing. 27 to 43% of the land areas in Bolivia, Chile, Ecuador and Peru are at risk due to desertification. In Argentina, Mexico and Paraguay, greater than half the land area is degraded by desertification and cannot be used for agriculture. In Central America, drought has caused increased unemployment and decreased food security - also causing migration of people. Similar impacts have been seen in rural parts of Mexico where about 1,000 km of land have been lost yearly due to desertification. In Argentina , desertification has

4980-666: The land. Agriculture is a main source of income for many desert communities. The increase in desertification in these regions has degraded the land to such an extent where people can no longer productively farm and make a profit. This has negatively impacted the economy and increased poverty rates. There is, however, increased global advocacy e.g. the UN SDG 15 to combat desertification and restore affected lands. Drylands occupy approximately 40–41% of Earth's land area and are home to more than 2 billion people. It has been estimated that some 10–20% of drylands are already degraded,

5063-424: The leeward face of a large dune. This phenomenon requires very specific circumstances to generate the sound. The dunes are silent throughout winter when humidity is retained in the sand. In the summer, when the sand is dry, the booming can be generated, but only on a slope of at least 30 degrees or more, on the leeward face of a dune; the same sand on the shallow, windward side cannot generate any noise. This phenomenon

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5146-426: The life sustenance in the desert supporting camels, goats and horses which are herded by nomads that travel through the desert. Most lakes also support a green ring of vegetation that populate the close vicinity around the lakes. Throughout the desert some lakes change color due to large populations of algae, Brine shrimp and mineral formations at different times in year. Evaporation can also allow others to turn into

5229-412: The life time of clouds which can result in less rainfall. Global food security is being threatened by desertification. The more that population grows , the more food that has to be grown. The agricultural business is being displaced from one country to another. For example, Europe on average imports over 50% of its food. Meanwhile, 44% of agricultural land is located in dry lands and it supplies 60% of

5312-442: The main reason is to maximize yields. By increasing productivity, they require a lot more fertilizer, pesticides, and labor to upkeep machinery. This continuous use of the land rapidly depletes the nutrients of the soil causing desertification to spread. Scientists agree that the existence of a desert in the place where the Sahara desert is now located is due to natural variations in solar insolation due to orbital precession of

5395-661: The marginalization of these zones. When unfavorable agri-climatic conditions are combined with an absence of infrastructure and access to markets, as well as poorly adapted production techniques and an underfed and undereducated population, most such zones are excluded from development. Desertification often causes rural lands to become unable to support the same sized populations that previously lived there. This results in mass migrations out of rural areas and into urban areas particularly in Africa creating unemployment and slums . The number of these environmental refugees grows every year, with projections for sub-Saharan Africa showing

5478-535: The most common causes of desertification was overgrazing, over consumption of vegetation by cattle or other livestock. However, the role of local overexploitation in driving desertification in the recent past is controversial. Drought in the Sahel region is now thought to be principally the result of seasonal variability in rainfall caused by large-scale sea surface temperature variations, largely driven by natural variability and anthropogenic emissions of aerosols (reflective sulphate particles ) and greenhouse gases. As

5561-490: The northern fringe of Africa, southern Africa, and Australia". Drylands cover 41% of the earth's land surface and include 45% of the world's agricultural land. These regions are among the most vulnerable ecosystems to anthropogenic climate and land use change and are under threat of desertification. An observation-based attribution study of desertification was carried out in 2020 which accounted for climate change, climate variability , CO 2 fertilization as well as both

5644-413: The period 1940 to 2015, the mean air temperature increased by 2.24 °C. The warmest ten-year period was during the latest decade to 2021. Precipitation has decreased by 7% over this period resulting in increased arid conditions throughout Mongolia. The Gobi desert continues to expand northward, with over 70% of Mongolia's land degraded through overgrazing, deforestation, and climate change. In addition,

5727-586: The physical expansion of deserts has been rejected as the concept has further evolved since then. There exists also controversy around the sub-grouping of types of desertification, including, for example, the validity and usefulness of such terms as "man-made desert" and "non-pattern desert". The immediate cause of desertification is the loss of most vegetation. This is driven by a number of factors, alone or in combination, such as drought, climatic shifts, tillage for agriculture, overgrazing and deforestation for fuel or construction materials. Though vegetation plays

5810-511: The potential to disrupt the nation's food supply. Techniques and countermeasures exist for mitigating or reversing desertification. For some of these measures, there are numerous barriers to their implementation. Yet for others, the solution simply requires the exercise of human reason. One proposed barrier is that the costs of adopting sustainable agricultural practices sometimes exceed the benefits for individual farmers, even while they are socially and environmentally beneficial. Another issue

5893-410: The precipitation is found in the upstream area, also showing a positive correlation with elevation. The evapotranspiration volumes are almost the same notwithstanding the high area difference among the three areas because of the consistent vegetation presence in the upstream (wild shrubs) and midstream (croplands) areas. In the E T {\displaystyle ET} term, when shifting from

5976-520: The project by planting 50,000 acres of trees. It is said to have improved land quality and caused an increase in economic opportunity in the region. Another major area that is being impacted by desertification is the Gobi Desert located in Northern China and Southern Mongolia. The Gobi Desert is the fastest expanding desert on Earth, as it transforms over 3,600 square kilometres (1,400 square miles) of grassland into wasteland annually. Although

6059-568: The river flow through the Hexi Corridor , a valley which once formed a significant portion of the Silk Road . The upper section of the river, also known as the Heihe (or 'Black River'), was first settled by the Chinese in about 100 B.C. Many outposts were created to protect Silk Road traders from the frequent attacks of barbarians , as the water-abundant valley of the river in relation with

6142-446: The rule in the Sahel region. The Sahel has lost approximately 650,000 km of its productive agricultural land over the past 50 years; the propagation of desertification in this area is considerable. The climate of the Sahara has undergone enormous variations over the last few hundred thousand years, oscillating between wet (grassland) and dry (desert) every 20,000 years (a phenomenon believed to be caused by long-term changes in

6225-402: The soil and restoration of its fertility is often achieved by plants. Of these, leguminous plants which extract nitrogen from the air and fix it in the soil, succulents (such as Opuntia ), and food crops/trees as grains , barley , beans and dates are the most important. Sand fences can also be used to control drifting of soil and sand erosion. Another way to restore soil fertility

6308-444: The soil is often done through the use of shelter belts , woodlots and windbreaks . Windbreaks are made from trees and bushes and are used to reduce soil erosion and evapotranspiration . Some soils (for example, clay ), due to lack of water can become consolidated rather than porous (as in the case of sandy soils). Some techniques as zaï or tillage are then used to still allow the planting of crops. Another technique that

6391-492: The total area affected by desertification being between 6 and 12 million square kilometers, that about 1–6% of the inhabitants of drylands live in desertified areas, and that a billion people are under threat from further desertification. The impact of climate change and human activities on desertification are exemplified in the Sahel region of Africa. The region is characterized by a dry hot climate, high temperatures and low rainfall (100–600 mm per year). So, droughts are

6474-524: The total balance of the river in this part is negative (that is more water is lost than acquired). After the stream gauge at Zhengyi, the river describes a wide north-east turn , developing its last 400 km in the western fringe of the Badain Jaran Desert . Apart from the physiological riparian vegetation, this last part of the hydrological basin is mainly desertic, and the water losses caused by both evaporation and deep percolation cause

6557-402: The vegetated (upstream and midstream) to the arid (downstream) areas, the transpiration element decreases in importance in favour of the simple evaporation . The volumetric balances, instead, show different signs: in the mountain area the input-over-output excess can be explained with the important precipitation volumes; in the midstream area the cultivations require a great amount of water that

6640-678: The water flux to weaken. This pattern has caused the river to be named Ruo (弱, Weak ). After the Langxinshan stream gauge, the river splits into two entities: the Dong He (東河, Eastern river ) and the Xi He (西河, Western river ) that follow on in the desert for another 220 km before emptying into two terminal lakes, the Sogo Nur and the Gaxun Nur , respectively, collectively forming

6723-477: The world's food production. Desertification is decreasing the amount of sustainable land for agricultural uses but demands are continuously growing. In the near future, the demands will overcome the supply. The violent herder–farmer conflicts in Nigeria , Sudan , Mali and other countries in the Sahel region have been exacerbated by climate change , land degradation and population growth . At least 90% of

6806-485: The world's tallest stationary dune. While the larger megadunes are stationary (with only the top layer of sand shifting), the smaller dunes are constantly shifting according to wind patterns. This makes desertification a problem in surrounding areas as the desert is constantly expanding. For tourists willing to go more out of their way, the Badain Jaran Desert is definitely a popular tourist attraction. Based upon weather patterns, temperature and sight-seeing possibilities

6889-618: Was that of the Princeton University Dictionary which defined it as "the process of fertile land transforming into desert typically as a result of deforestation , drought or improper/inappropriate agriculture". This definition clearly demonstrated the interconnectedness of desertification and human activities, in particular land use and land management practices. It also highlighted the economic, social and environmental implications of desertification. However, this original understanding that desertification involved

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