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50-541: The desert is expanding in size. The expansion of the Tengger and its neighbour, the Badain Jaran Desert , has been apparent since the 1950s, when large volumes of water were diverted from rivers to feed agricultural expansion and huge tracts of forest were removed. Since 1958, local governments have mobilised residents for afforestation campaigns to prevent the desert's spread. By 2004, the desert's expansion

100-412: A chorion coating which has a brown colour. These eggs, also known as cysts, are metabolically inactive and can remain in total stasis for two years while in dry oxygen-free conditions, even at temperatures below freezing. This characteristic is called cryptobiosis , meaning "hidden life". While in cryptobiosis, brine shrimp eggs can survive temperatures of liquid air (−190 °C or −310 °F) and

150-557: 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

200-455: A model organism for use in toxicological assays, despite the recognition that it is too robust an organism to be a sensitive indicator species . In pollution research Artemia , the brine shrimp, has had extensive use as a test organism and in some circumstances is an acceptable alternative to the toxicity testing of mammals in the laboratory. The fact that millions of brine shrimp are so easily reared has been an important help in assessing

250-468: 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

300-405: A segmented body to which is attached broad leaf-like appendages . The body usually consists of 19 segments, the first 11 of which have pairs of appendages, the next two which are often fused together carry the reproductive organs, and the last segments lead to the tail. The total length is usually about 8–10 millimetres (0.31–0.39 in) for the adult male and 10–12 mm (0.39–0.47 in) for

350-400: A small percentage can survive above boiling temperature (105 °C or 221 °F) for up to two hours. Once placed in briny (salt) water, the eggs hatch within a few hours. The nauplius larvae are less than 0.4 mm in length when they first hatch. Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilisation . Thelytoky

400-512: Is a desert in China which spans the provinces of Gansu , Ningxia and Inner Mongolia . It covers an area of 49,000 square kilometers (19,000 sq mi; 12,000,000 acres). By size it is the third largest desert in China. 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

450-505: Is a particular form of parthenogenesis in which the development of a female individual occurs from an unfertilised egg. Automixis is a form of thelytoky, but there are different kinds of automixis. The kind of automixis relevant here is one in which two haploid products from the same meiosis combine to form a diploid zygote . Diploid Artemia parthenogenetica reproduce by automictic parthenogenesis with central fusion (see diagram) and low but nonzero recombination. Central fusion of two of

500-512: 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

550-587: Is achieved by the rhythmic beating of the appendages acting in pairs. Respiration occurs on the surface of the legs through fibrous, feather-like plates (lamellar epipodites). Males differ from females by having the second antennae markedly enlarged, and modified into clasping organs used in mating. Adult female brine shrimp ovulate approximately every 140 hours. In favourable conditions, the female brine shrimp can produce eggs that almost immediately hatch. While in extreme conditions, such as low oxygen level or salinity above 150‰, female brine shrimp produce eggs with

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600-683: 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), 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

650-449: 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 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

700-677: 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 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

750-455: 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

800-512: 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

850-662: Is the only genus in the family Artemiidae . The first historical record of the existence of Artemia dates back to the first half of the 10th century AD from Lake Urmia , Iran , with an example called by an Iranian geographer an "aquatic dog", although the first unambiguous record is the report and drawings made by Schlösser in 1757 of animals from Lymington , England . Artemia populations are found worldwide, typically in inland saltwater lakes, but occasionally in oceans. Artemia are able to avoid cohabiting with most types of predators, such as fish, by their ability to live in waters of very high salinity (up to 25%). The ability of

900-547: The Artemia genome was assembled and annotated , revealing a genome containing an unequaled 58% of repeats , genes with unusually long introns and adaptations unique to the extremophilic nature of Artemia in high salt and low oxygen environments. These adaptations include a unique energy-intensive endocytosis -based salt excretion strategy resembling salt excretion strategies of plants, as well as several survival strategies for extreme environments it has in common with

950-446: The Artemia to produce dormant eggs, known as cysts , has led to extensive use of Artemia in aquaculture . The cysts may be stored indefinitely and hatched on demand to provide a convenient form of live feed for larval fish and crustaceans . Nauplii of the brine shrimp Artemia constitute the most widely used food item, and over 2,000 metric tons (2,200 short tons) of dry Artemia cysts are marketed worldwide annually with most of

1000-469: 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

1050-540: The Mediterranean area about 5.5  million years ago , around the time of the Messinian salinity crisis . The Laboratory of Aquaculture & Artemia Reference Center at Ghent University possesses the largest known Artemia cyst collection, a cyst bank containing over 1,700 Artemia population samples collected from different locations around the world. Artemia is a typical primitive arthropod with

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1100-716: The United States Fish and Wildlife Service to add A. monica to the endangered species list under the Endangered Species Act (1973). The diversion of water by the Los Angeles Department of Water and Power resulted in rising salinity and concentration of sodium hydroxide in Mono Lake. Despite the presence of trillions of brine shrimp in the lake, the petition contended that the increase in pH would endanger them. The threat to

1150-536: 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

1200-573: The naupliar eye , is situated anteriorly in the centre of the head and is the only functional optical sense organ in the nauplii, which is functional until the adult stage. Brine shrimp can tolerate any levels of salinity from 25 ‰ to 250‰ (25–250 g/L), with an optimal range of 60‰–100‰, and occupy the ecological niche that can protect them from predators. Physiologically, optimal levels of salinity are about 30–35‰, but due to predators at these salt levels, brine shrimp seldom occur in natural habitats at salinities of less than 60–80‰. Locomotion

1250-548: 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

1300-505: 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. Brine shrimp Artemia is a genus of aquatic crustaceans also known as brine shrimp , Aqua Dragons or sea monkeys . It

1350-775: The Mediterranean region. Among the highly localized species are A. urmiana from Lake Urmia in Iran. Once abundant, the species has drastically declined due to drought, leading to fears that it was almost extinct. However, a second population of this species has recently been discovered in the Koyashskoye Salt Lake , Ukraine . A. monica , the species commonly known as Mono Lake brine shrimp, can be found in Mono Lake , Mono County, California . In 1987, Dennis D. Murphy from Stanford University petitioned

1400-580: The Russian Bion-3 ( Cosmos 782 ), Bion-5 ( Cosmos 1129 ), Foton 10, and Foton 11 flights. Some of the Russian flights carried European Space Agency experiments. On Apollo 16 and Apollo 17, the cysts traveled to the Moon and back. Cosmic rays that passed through an egg would be detected on the photographic film in its container. Some eggs were kept on Earth as experimental controls as part of

1450-412: 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

1500-456: The brain; instead, local nervous system ganglia may control some regulation or synchronisation of these functions. Autotomy, the voluntary shedding or dropping of parts of the body for defence, is also controlled locally along the nervous system. Artemia have two types of eyes. They have two widely separated compound eyes mounted on flexible stalks. These compound eyes are the main optical sense organ in adult brine shrimps. The median eye, or

1550-622: 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

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1600-494: 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,

1650-645: 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

1700-734: The cyst. Wild brine shrimp eat microscopic planktonic algae . Cultured brine shrimp can also be fed particulate foods including yeast , wheat flour , soybean powder or egg yolk . Artemia comprises sexually reproducing, diploid species and several obligate parthenogenetic Artemia populations consisting of different clones and ploidies (2n->5n). Several genetic maps have been published for Artemia . The past years, different transcriptomic studies have been performed to elucidate biological responses in Artemia , such as its response to salt stress, toxins, infection and diapause termination. These studies also led to various fully assembled Artemia transcriptomes . Recently,

1750-583: The cysts being harvested from the Great Salt Lake in Utah. In addition, the resilience of Artemia makes them ideal animals for running biological toxicity assays and it has become a model organism used to test the toxicity of chemicals. Breeds of Artemia are sold as novelty gifts under the marketing name Sea-Monkeys . The brine shrimp Artemia comprises a group of seven to nine species very likely to have diverged from an ancestral form living in

1800-462: 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

1850-442: 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 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

1900-511: The effects of a large number of environmental pollutants on the shrimps under well controlled experimental conditions. Overall, brine shrimp are abundant, but some populations and localized species do face threats, especially from habitat loss to introduced species . For example, A. franciscana of the Americas has been widely introduced to places outside its native range and is often able to outcompete local species, such as A. salina in

1950-663: The extremophilic tardigrade . Fish farm owners search for a cost-effective, easy to use, and available food that is preferred by the fish. From cysts, brine shrimp nauplii can readily be used to feed fish and crustacean larvae just after a one-day incubation . Instar I (the nauplii that just hatched and with large yolk reserves in their body) and instar II nauplii (the nauplii after first moult and with functional digestive tracts) are more widely used in aquaculture, because they are easy for operation, rich in nutrients, and small, which makes them suitable for feeding fish and crustacean larvae live or after drying. Artemia found favor as

2000-522: 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)

2050-480: The female, but the width of both sexes, including the legs, is about 4 mm (0.16 in). The body of Artemia is divided into head, thorax , and abdomen. The entire body is covered with a thin, flexible exoskeleton of chitin to which muscles are attached internally and which is shed periodically. In female Artemia, a moult precedes every ovulation . For brine shrimp, many functions, including swimming, digestion and reproduction are not controlled through

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2100-426: The haploid products of meiosis (see diagram) tends to maintain heterozygosity in transmission of the genome from mother to offspring, and to minimise inbreeding depression . Low crossover recombination during meiosis likely restrains the transition from heterozygosity to homozygosity over successive generations. In their first stage of development, Artemia do not feed but consume their own energy reserves stored in

2150-496: 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 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

2200-504: The lake's water levels was addressed by a revision to California State Water Resources Control Board 's policy, and the US Fish and Wildlife Service found on 7 September 1995 that the Mono Lake brine shrimp did not warrant listing. Scientists have taken the eggs of brine shrimp to outer space to test the impact of radiation on life. Brine shrimp cysts were flown on the U.S. Biosatellite 2 , Apollo 16 , and Apollo 17 missions, and on

2250-424: 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

2300-565: The southern region in the desert. These lakes can easily be found in the larger valleys between large dunes. They are believed to provide 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

2350-553: The tests. Also, as the take-off in a spacecraft involves a lot of shaking and acceleration , one control group of egg cysts was accelerated to seven times the force of gravity and vibrated mechanically from side to side for several minutes so that they could experience the same violence of a rocket take-off. About 400 eggs were in each experimental group. All the egg cysts from the experiment were then placed in salt water to hatch under optimum conditions. The results showed A. salina eggs are highly sensitive to cosmic radiation; 90% of

2400-486: 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

2450-472: Was estimated as 10 metres per year in some areas. In 2007, a non-profit organisation founded by residents of Minqin County created square ditches lined with hay and grass that they later planted with saxaul to stabilise the sand dunes. In 2010, the central and regional governments announced a five-year reforestation plan to create a 202-km green belt between the Tengger and Badain Jaran deserts. The project

2500-530: Was estimated to receive 280 million yuan in funding and involve the relocation of 1,000 residents. 38°42′N 104°42′E  /  38.700°N 104.700°E  / 38.700; 104.700 This Inner Mongolia location article is a stub . You can help Misplaced Pages by expanding it . Badain Jaran Desert The Badain Jaran Desert ( Chinese : 巴 丹 吉 林 沙 漠 ; pinyin : Bādānjílín Shāmò )

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