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99-457: Mengjin began its life as an ancient ferry crossing for the Yellow River . According to legend, King Wu of Zhou crossed the Yellow River at this location, after forming an alliance with the other nobles, leading to the theory that the original name was actually ( 盟 津 ; Méngjīn ; 'ferry crossing of the alliance') rather than 孟 津 ; Mèngjīn . According to this theory, it

198-474: A "war-induced natural disaster". The goal of the operation was to stop the advancing Japanese troops by following a strategy of "using water as a substitute for soldiers". The 1938 flood of an area covering 54,000 km (20,800 sq mi) took some 500,000 to 900,000 Chinese lives, along with an unknown number of Japanese soldiers. The flood prevented the Japanese Army from taking Zhengzhou , on

297-669: A drastic eastward turn at its confluence with the Wei at Tongguan in Shaanxi . However, the official division for the middle reaches of the river run from Hekou in Togtoh County , Inner Mongolia , to Zhengzhou , Henan . The middle reaches are 1,206 km (749 mi) long, with a basin area of 344,000 square kilometers (133,000 sq mi), 45.7% of the total, with a total elevation drop of 890 m (2,920 ft), an average drop of 0.074%. There are 30 large tributaries along

396-609: A north–south extent of about 1,100 km (680 mi). Its total drainage area is about 795,000 square kilometers (307,000 sq mi). According to the China Exploration and Research Society, the source of the Yellow River is at 34°29′31″N 96°20′25″E  /  34.49194°N 96.34028°E  / 34.49194; 96.34028 in the Bayan Har Mountains near the eastern edge of

495-399: A population of 120 million people, while over 420 million people live in the immediate provinces which rely on it as a water source. The basin comprises 13 percent of China's cultivated land area. The area receives very uneven rainfall, only 2 percent of China's water runoff —water and sediment flow has decreased five-fold since the 1970s, and until recently, the river frequently did not reach

594-436: A temperature around 0 °C (32 °F) or even below lower. This favors the frost weathering process and freeze-thaw cycles which lead to physical weathering of the rocks at the mountain top. This process changes the rocks into small sized grains. High relief and gradient: When the melting water and river water from the mountain water flows down from the mountain top, it creates a large amount of potential energy because of

693-593: Is "River of the Peacock" ( Tibetan : རྨ ་ ཆུ , Wylie : rma.chu , THL : Ma chu ; 玛曲 ; 瑪曲 ; Mǎ qǔ ). The Yellow River first formed sometime during the Late Miocene , Pliocene or Pleistocene , as a result of the Tibetan Plateau being uplifted. The river has long been critical to the development of northern China, and is regarded by scholars as a cradle of civilization . Flooding of

792-546: Is at the northwest of the Loess Plateau while the finest is at the southeast. Some studies found that the loess that formed during Middle Pleistocene is expansive and thick. Therefore, the main period for the formation of the Loess Plateau is Middle Pleistocene. Most of the loess in the west of Liupan Mountain is yellow. However, the loess in the east has many different colors, such as deep reddish-orange, brownish-gold. The color differences indicate that Liupan Mountain

891-419: Is formed. Two types of loess are defined by their formation process. Typical loess is loess that is deposited during late Pleistocene and Holocene. It is formed under arid or semi-arid conditions. Secondary loess is loess that is compacted by upper loess and does not experience the weathering and carbonation process. Also, it is formed by the transformation of fluvial and lake loess in semi-arid areas. Both

990-421: Is located in the northwest of the Loess Plateau. Wind escarpment in the Loess Plateau marks a boundary between Mu Us Desert and the Loess Plateau. It also represents a transition from loess accumulation to wind erosion in the Loess Plateau. Many linear bedrock ridges are formed behind the wind escarpment, which are parallel to the wind direction. In the northern Loess Plateau, the bedrock ridges are pointing towards

1089-568: Is running to the sea with sufficient volume, 1.4 billion tons are carried to the sea per year. One estimate gives 34 kilograms of silt per cubic meter, as opposed to 10 for the Colorado and 1 for the Nile . Its average discharge is said to be 2,110 cubic meters per second (32,000 for the Yangtze), with a maximum of 25,000 and minimum of 245. However, since 1972, it often runs dry before it reaches

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1188-493: Is the most important factor. During Spring, many strong dust storms happen in the Loess Plateau which usually last for more than two days. With a longer dust storm event, the loess can travel a longer distance. The dust storm is blown from northwest to the Loess Plateau. Although the source of loess materials is from the Gobi Desert and the sand deserts, they are not produced by those deserts. The three mountains, including

1287-469: Is transporting, the dust may deposit at the windward slope of the mountain. Monsoon is also important to determine the source of loess because monsoon will affect the wind direction. There are winter monsoonal winds flowing from Mongolia because of the high-pressure cell in Siberian-Mongolia. This plays an important role in transporting dust and loess to the Loess Plateau. Dust storm: This

1386-540: The 1897 flood . The 1931 flood killed an estimated 1,000,000 to 4,000,000, and is the worst natural disaster recorded (excluding famines and epidemics). On 9 June 1938, during the Second Sino-Japanese War , Nationalist troops under Chiang Kai-shek broke the levees holding back the river near the village of Huayuankou in Henan, causing what has been called by Canadian historian, Diana Lary,

1485-560: The Bayan Har Mountains , and the Anemaqen ( Amne Machin ) Mountains in Qinghai. The river water is clear and flows steadily. Crystal clear lakes are characteristic of this section. The two main lakes along this section are Lake Gyaring (Zhaling) and Lake Ngoring (Eling), with capacities of 4.7 billion and 10.8 billion m (166 and 381 billion ft ), respectively. At elevations over 4,290 m (14,070 ft) above sea level they are

1584-615: The Bohai Sea . The river is named for the yellow color of its water, which comes from the large amount of sediment discharged into the water as the river flows through the Loess Plateau . The Yellow River basin was the birthplace of ancient Chinese civilization . According to traditional Chinese historiography , the Xia dynasty originated on its banks around 2100 BC; Sima Qian 's Shiji ( c.  91 BC ) record that

1683-655: The Gobi Desert and the deserts nearby, including the Tengger Desert , Badain Jaran Desert , Ulan Buh Desert, Mu Us Desert and Hobq Desert. However, the main source is the Gobi Desert. This is proven because their minerals, isotopes and chemicals are similar. Both of the places have quartz as the main mineral of the loess. The value of Sr/ Sr is extremely high and both of them have high Eu/Yb and Eu/Eu ratios, which are trace elements . These data prove that

1782-462: The Gulf of Bohai , draining a basin of 752,443 square kilometers (290,520 sq mi) which nourishes 140 million people with drinking water and irrigation. The Yellow River passes through seven present-day provinces and two autonomous regions , namely (from west to east) Qinghai , Sichuan , Gansu , Ningxia , Inner Mongolia , Shaanxi , Shanxi , Henan , and Shandong . Major cities along

1881-561: The Hangu Pass ; it saw numerous battles and was also an important chokepoint protecting the Han capitals of Chang'an and Luoyang . Major flooding in AD 11 is credited with the downfall of the short-lived Xin dynasty , and another flood in AD 70 returned the river north of Shandong on essentially its present course. From around the beginning of the 3rd century, the importance of the Hangu Pass

1980-530: The Loess Plateau , is a plateau in north-central China formed of loess , a clastic silt-like sediment formed by the accumulation of wind-blown dust . It is located southeast of the Gobi Desert and is surrounded by the Yellow River . It includes parts of the Chinese provinces of Qinghai , Gansu , Shaanxi and Shanxi . The depositional setting of the Chinese Loess Plateau was shaped by

2079-479: The Spring and Autumn period and Qin dynasty indicate that the Yellow River at that time flowed considerably north of its present course. These accounts show that after the river passed Luoyang , it flowed along the border between Shanxi and Henan Provinces, then continued along the border between Hebei and Shandong before emptying into Bohai Bay near present-day Tianjin . Another outlet followed essentially

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2178-535: The Yangtze : one in the western headwaters of the rivers where they are closest to one another, another from the upper reaches of the Han River , and a third using the route of the old Grand Canal . Due to its heavy load of silt the Yellow River is a depositing stream – that is, it deposits part of its carried burden of soil in its bed in stretches where it is flowing slowly. These deposits elevate

2277-710: The Yushu Tibetan Autonomous Prefecture . The source tributaries drain into Gyaring Lake and Ngoring Lake on the western edge of Golog Prefecture high in the Bayan Har Mountains of Qinghai . In the Zoige Basin along the boundary with Gansu , the Yellow River loops northwest and then northeast before turning south, creating the " Ordos Loop ", and then flows generally eastward across the North China Plain to

2376-421: The 'Earth Suspended River' . At Kaifeng , Henan, the Yellow River is 10 meters (33 ft) above the ground level. Tributaries of the Yellow River listed from its source to its mouth include: The lower reaches of the Yellow River have no tributaries. The Yellow River is notable for the large amount of silt it carries—1.6 billion tons annually at the point where it descends from the Loess Plateau . If it

2475-506: The Bayan Har Mountains and ending at Hekou Town ( Togtoh County ), Inner Mongolia just before it turns sharply to the south. This segment has a total length of 3,472 kilometers (2,157 mi) and total basin area of 386,000 square kilometers (149,000 sq mi), 51.4% of the total basin area. Along this length, the elevation of the Yellow River drops 3,496 meters (11,470 ft), with an average grade of 0.10%. The source section flows mainly through pastures, swamps, and knolls between

2574-725: The Gobi Altay Mountains, the Hangayn Mountains and the Qilian Mountains are responsible for making loess materials for the desert and plateau. High elevation: According to the environmental lapse rate , the air temperature will decrease by 6 °C (43 °F) per 1,000 metres (3,300 ft). Therefore, the higher the mountain, the more extreme climate. All three mountains are higher than 2,500 metres (8,200 ft), ranging from 2,500 to 5,500 metres (8,200 to 18,000 ft). The mountain top may have

2673-482: The Jinshan Valley. The abundant hydrodynamic resources stored in this section make it the second most suitable area to build hydroelectric power plants. The famous Hukou Waterfall is in the lower part of this valley on the border of Shanxi and Shaanxi . In the lower reaches, from Zhengzhou to its mouth, a distance of 786 km (488 mi), the river is confined to a levee -lined course as it flows to

2772-477: The Loess Plateau during interglacial periods by southeasterly prevailing winds and winter monsoon winds. After the deposition of sediments on the plateau, they were gradually compacted to form loess under the arid climate. The Loess Plateau is one of the largest and thickest loess plateaus in the world. Its 635,000 km2 area corresponds to around 6.6% of the land area in China. Around 108 million people inhabit

2871-578: The Loess Plateau was shaped by the tectonic movement since Neogene. After that, because of the East Asia Monsoon in Quaternary, the loess and different erosional features started to form. However, because of human activities, many areas in the Loess Plateau turned into erosional environments. Loess does not necessarily mean the same as silt. Loess is yellow eolian sediments that were transported by wind from an arid or semi-arid region during

2970-447: The Loess Plateau wind escarpment. Because of the streamline compression of the wind escarpment, the wind speed is increased. As a result, the Loess Plateau is not only a site of loess deposition but also a source of dust because of strong wind erosion. Wind erosion is very severe during the glacial period. During the glacial period, there is very little vegetation, so it favors wind erosion. Loess vertical joints distribution depends on

3069-412: The Loess Plateau, the contribution of gully erosion on total sediment production in the hilly areas is about 60% to 90%. It is serious in the Loess Plateau. To know the contribution of gully erosion, we can measure the gully volume changes. There are three types of gullies in the Loess Plateau, including floor gullies, hill slope gullies and valley bank gullies. In conclusion, the geomorphic outline of

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3168-399: The Loess Plateau. Because of the strong winds, erosion is also powerful across the plateau. Therefore, erosional features, including wind escarpments, loess vertical joints and gullies are present. In the past few decades, the environment and climate has changed, including the rainfall pattern, vegetation cover, and the natural hazards . These changes may relate to human development in

3267-506: The North China Plain to irrigated agriculture. Construction began in earnest in 1957. From the 1970s to the 1990s, the dry-up trends accelerated, with the Yellow River failing to reach its mouth for an average of approximately 180 days per year in the 1990s. In 1997, the Yellow River did not reach the sea for 226 consecutive days. The Yellow River basin has an east–west extent of about 1,900 kilometers (1,180 mi) and

3366-399: The Quaternary period. Around 6% of the land in the world is covered with loess. Loess record the past climate and environment. The Chinese Loess Plateau is one of the largest sinks of loess in the world. When the sediments are transported to the Loess Plateau, they are silt materials. After they deposit in arid areas and under strong chemical weathering and the process of carbonation, loess

3465-566: The Xia were founded after the tribes around the Yellow River united to combat the frequent floods in the area. The river has provided fertile soil for agriculture, but since then has flooded and changed course frequently, with one estimate counting 1,593 floods in the 2,540 years between 595 BC and 1946 AD. As such, the Yellow River has been considered a blessing and a curse throughout history, and has been nicknamed both "China's Pride" and "China's Sorrow". The Yellow River's basin presently has

3564-477: The Yellow River Basin by the south dike of the Yellow River. The total drop in elevation of the lower reaches is 93.6 m (307 ft), with an average grade of 0.012%. The silts received from the middle reaches form sediments here, elevating the river bed. Excessive sediment deposits have raised the riverbed several meters above the surrounding ground. That is why this part of the river is called

3663-421: The Yellow River is 3.91 billion tons in 1933. The highest silt concentration level was recorded in 1977 at 920 kg/m (57.4 lb/ft ). These sediments later deposit in the slower lower reaches of the river, elevating the river bed and creating the famous "river above ground". From Hekou to Yumenkou, the river passes through the longest series of continuous valleys on its main course, collectively called

3762-439: The Yellow River, arranged according to the first year of operation (in brackets): As reported in 2000, the 7 largest hydro power plants (Longyangxia, Lijiaxia, Liujiaxia, Yanguoxia, Bapanxia, Daxia and Qinglongxia) had the total installed capacity of 5,618 MW. The main bridges and ferries by the province names in the order of downstream to upstream are: Shandong Loess Plateau The Chinese Loess Plateau , or simply

3861-464: The Yellow River. One, which he identifies as Confucian , advocated containing the river between higher levees, thus maximizing the amount of river basin land that could be cultivated. The other, which he associates with Taoism , favored lower levees separated by as much as 5-10 kilometers. In one particular long-running debate during the 11th century reigns of the Renzong and Shenzong emperors, when

3960-417: The amount and grain size of the sediments will increase. More than 90% of the loess is calcite , feldspar , mica and quartz . Among that, around 50% is quartz. The 10% left are orthoclase , viitaniemiite , sudoite , clinochlore and nimite . From the mineralogical, isotopic, and chemical results, it is easy to find the provenance of the loess. The sources of loess in the Chinese Loess Plateau are

4059-400: The apparent sedimentation rate also increases. There are two reasons. There are other factors that control the grain size changes. Besides the variations in the wind intensity, the grain size may also affect by the aridity of the source areas. This changes the transporting distance of the sediments. During interglacial periods, the Loess Plateau retreated northwesterly while it moves towards

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4158-579: The central plains from the Khitai was overruled in 1020: the Chanyuan Treaty between the two states had expressly forbidden the Song from establishing new moats or changing river courses. Breaches occurred regardless: one at Henglong in 1034 divided the course in three and repeatedly flooded the northern regions of Dezhou and Bozhou . The Song worked for five years futilely attempting to restore

4257-516: The deadliest natural disasters ever recorded. Before modern disaster management, when floods occurred, some of the population might initially die from drowning and many more would suffer later from the ensuing famine and spread of diseases. In Chinese mythology , the giant Kua Fu drained the Yellow River and the Wei River to quench his burning thirst as he pursued the Sun. Historical documents from

4356-481: The desert are from the mountain. After that, the wind will transport the sediments to the Loess Plateau and sort the sediments. Tectonic activities: When there are tectonic activities in High Asia, energy is released. This causes the denudation of the rock and downcutting of rivers of the mountains. Loess materials are formed from the mountains during tectonic activities. Besides, the sediments are also produced by

4455-411: The development of the joints. Many vertical loess joints can be easily found on the vertical cliffs of tableland. The joints and the loess-paleosol interface are orientated perpendicularly. Also, in a dry loess layer, vertical loess joints are the wet part of it. Therefore, it is very difficult to notice the loess vertical joints in deep strata. The water from rainfall and irrigation will infiltrate into

4554-541: The end of Tang dynasty , for unclear reasons. In the Shaanxi loess plateau, it is referred to as 'river, my lord' ( 老爺河 , [lo˦˩˨ i˧ xɤu̯˧] ) in the Jin language. In Mongolian , it is called Šar mörön ( Шар мөрөн 'yellow river') or Khatan gol ( Хатан гол 'queen river'). The river is mentioned in the Kul Tigin stele as the 'green river' ( Old Turkic : yašïl ügüz , 𐰖𐱁𐰞𐰽𐰺𐰍). The Tibetan name

4653-400: The flat North China Plain , sometimes taking a new channel and inundating most farmland, cities or towns in its path. The traditional Chinese response of building higher and higher levees along the banks sometimes also contributed to the severity of the floods: When flood water did break through the levees, it could no longer drain back into the river bed as it would after a normal flood, as

4752-464: The floods is the large amount of fine-grained loess carried by the river from the Loess Plateau , which is continuously deposited along the bottom of its channel. The sedimentation causes natural dams to slowly accumulate. These subaqueous dams are unpredictable and generally undetectable. Eventually, the enormous amount of water needs to find a new way to the sea, forcing it to take the path of least resistance . When this happens, it bursts out across

4851-499: The founding of the Ming dynasty . The course changed again in 1391 when the river flooded from Kaifeng to Fengyang in Anhui . It was finally stabilized by the eunuch Li Xing during the public works projects following the 1494 flood . The river flooded many times in the 16th century, including in 1526, 1534, 1558, and 1587. Each flood affected the river's lower course. The 1642 flood

4950-423: The infiltration of water and accumulation of the sediments in the water. In the underdevelopment stage a few or nearly zero joints are found. And lastly in the undeveloped stage no vertical joint is found. The loess is very dry. The average moisture content is 16.22%. Gully erosion acts as an important source for sediments. If an area has gully erosion, it means that the area has serious land degradation. In

5049-425: The loess is from the Gobi Desert. The Gobi Desert is located at the north of the plateau. Although the distance between the Gobi Desert and the Chinese Loess Plateau is quite far, it is possible that the loess can travel such a great distance. There are a few reasons why the source of loess is from the Gobi Desert and the sand deserts. Prevailing wind : The prevailing wind of the sand deserts and Gobi Desert are from

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5148-519: The loess strata through the vertical joint surface and pore concentration zone. The joint systems in the loess strata are of different sizes, properties, periods, and origins. Loess Vertical Joints distribute all over the loess plateau. The joints in landslides can be categorized by their different features. The original joints are formed on the major scarp, minor scarp, original vertical cliffs and flanks. They are no displacement and closed. Unloading vertical joints and weathering vertical joints are at

5247-475: The loess structure, water moisture, strata and microtopography. There are vertical development features and lateral development features. Vertically, joints can be found in different loess strata, including late, middle and early Pleistocene loess layers. It is one of the most significant structures of the Loess Plateau. The development and size of the vertical loess joints depend on the vegetation coverage and slope. Steep slope and poor vegetation coverage favor

5346-433: The middle reaches, and the water flow is increased by 43.5% on this stage. The middle reaches contribute 92% of the river's silts. The middle stream of the Yellow River passes through the Loess Plateau , where substantial erosion takes place. The large amount of mud and sand discharged into the river makes the Yellow River the most sediment -laden river in the world. The highest recorded annual level of silts discharged into

5445-445: The mountains are different in different locations. One of the highest mountains in the Loess Plateau is called Mahan Mountain. The elevation of this mountain is around 3,670 metres (12,040 ft), which is 1,300 metres (4,300 ft) higher than the loess line. It is a flat-topped mountain and has paleo-peneplain remnants on the mountain top. Some of the mountain slopes, especially the windward slope (north slope), were forested in

5544-510: The next belt, which is the river valley belt. The River valley belt includes flood plains , river terraces and river beds. The terraces with higher height are mostly covered with thick loess. It will change to another form of landscape, which is loess ridge, by strong erosion. If the erosion is weak, the higher terraces will change to loess tableland. These flat river basins , which include valley flat and lower terraces, are important for construction and agricultural activities. Mu Us Desert

5643-559: The north Loess Plateau. The geomorphology of the Loess Plateau is formed by the erosion and deposition of loess. In the Loess Plateau, the geomorphology usually changes from rocky mountains to Alluvial plain at piedmont to river valley belt. This pattern keeps repeating from the Northwest to the Southeast of the Loess Plateau. The height of the rocky mountains is much higher than the loess deposit. The height and morphology of

5742-530: The northeast across the North China Plain before emptying into the Bohai Sea . The basin area in this stage is only 23,000 square kilometers (8,900 sq mi), a mere 3% of the total, because few tributaries add to the flow in this stage; nearly all rivers to the south drain into the Huai River , whereas those to the north drain into the Hai River . The Huai River Basin, for example, is separated from

5841-457: The northeast. However, the direction of the ridges slowly rotates to the North in the central Loess Plateau. At North Loess Plateau, the ridges are oriented 118° ±14° while they are oriented 179° ± 11° at central Loess Plateau. This indicates the role of wind erosion. The monsoon wind direction in Quaternary is consistent with modern climatology. To observe near-surface wind vectors, they compared

5940-467: The northwest, it carries the loess of different sizes. When it arrives at the Loess Plateau, the energy of the wind starts to decrease, so it drops the largest and heaviest loess first. It continues to move towards the southeast of the Loess Plateau, the energy of the wind keeps decreasing. Therefore, the finest loess materials are deposited at the southeast end of the Plateau. That is why the coarsest loess

6039-403: The northwest. Since the Gobi Desert and the sand deserts are located northwest of the Chinese Loess Plateau, the prevailing wind builds a linkage for all these places. The loess can travel to the plateau through the prevailing wind. No mountain in between: In the transport pathway of the dust, there is no high mountain in between. In the situation where high mountains block the dust when the dust

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6138-474: The past century, each causing tremendous loss of life and property. Nowadays, explosives dropped from aircraft are used to break the ice dams before they become dangerous. Before modern dams appeared in China, the Yellow River used to be extremely prone to flooding. In the 2,540 years from 595 BC to 1946 AD, the Yellow River has been reckoned to have flooded 1,593 times, shifting its course 26 times noticeably and nine times severely. These floods include some of

6237-431: The past. The alluvial plain at piedmont is composed of Alluvial fans which can be found in this area, and which are located at the foot of the rocky mountains. The size of this belt depends on the amount of runoff and weathering materials from the rocky mountains. Old alluvial fans are covered with eolian loess . Further from the rocky mountains, loess tableland and loess "Ping" can be found and even links with

6336-456: The plateau; Chinese environmental officials are trying to find sustainable ways to manage the region. There are three main types of morphology in the Loess Plateau. They are loess platform, loess ridges, and loess hills . Loess tableland is flat and with many loess strata. It is mostly located at south Loess Plateau. Loess ridges are formed by erosion and are located at the central Loess Plateau. Loess Hills are conical dunes and are located at

6435-540: The present course of the Yellow River include (from west to east) Lanzhou , Yinchuan , Wuhai , Baotou , Luoyang , Zhengzhou , Kaifeng , and Jinan . The current mouth of the Yellow River is located at Kenli County , Shandong. The river is commonly divided into three stages. These are roughly the northeast of the mountainous Tibetan Plateau , the Ordos Loop and Loess Plateau , and the North China Plain . However, different scholars have different opinions on how

6534-534: The present course. The river left these paths in 602 BC and shifted several hundred kilometers to the east. Sabotage of dikes, canals, and reservoirs and deliberate flooding of rival states became a standard military tactic during the Warring States period . As the Yellow River valley was the major entryway to the Guanzhong area and the state of Qin from the North China Plain , Qin heavily fortified

6633-485: The previous course – using over 35,000 employees, 100,000 conscripts, and 220,000 tons of wood and bamboo in a single year  – before abandoning the project in 1041. The more sluggish river then occasioned a breach at Shanghu that sent the main outlet north towards Tianjin in 1048. In 1128, Song troops under the Kaifeng governor Du Chong ( 杜 充 , Dù Chōng , d.   1141) breached

6732-441: The rainy season from July to October, when 60% of the annual volume of the river flows. Maximum demand for irrigation is needed between March and June. In order to capture excess water for use when needed and for flood control and electricity generation, several dams have been built, but their expected life is limited due to the high silt load. A proposed South–North Water Transfer Project involves several schemes to divert water from

6831-477: The regions along the river are mostly deserts and grasslands, with very few tributaries. The flow is slow. The Hetao Plain has a length of 900 km (560 mi) and width of 30 to 50 km (19 to 31 mi). It is historically the most important irrigation plain along the Yellow River. The Ordos Loop formed by an enormous twist of the Yellow River, beginning at Zhongning County in Ningxia and ending with

6930-617: The river bed was sometimes now higher than the surrounding countryside. These changes could cause the river's mouth to shift as much as 480 km (300 mi), sometimes reaching the ocean to the north of the Shandong Peninsula and sometimes to the south. Another historical source of devastating floods is the collapse of upstream ice dams in Inner Mongolia with an accompanying sudden release of vast quantities of impounded water. There have been 11 such major floods in

7029-467: The river flows generally eastwards before entering the 1,500 km (930 mi) long Ordos Loop, which runs northeast at Gansu through the Ordos Plateau and turns east in Inner Mongolia . The river then turns sharply southwards to form the border between Shanxi and Shaanxi , turns eastwards at its confluence with the Wei River , and flows across the North China Plain before emptying into

7128-569: The river has also caused much destruction, including multiple floods that have resulted in the deaths of over one million people. Among the deadliest were the 1332–33 flood or 1344 Yellow River flood during the Yuan dynasty , the 1887 flood during the Qing dynasty which killed anywhere from 900,000 to 2 million people, and a Republic of China era 1931 flood (part of a massive number of floods that year ) that killed 1–4 million people. The cause of

7227-587: The river increased the water's power and this in turn increased its ability to flush sediment. The difficult situation around the confluence of the Yellow River, the Huai, and the Grand Canal, however, still led to a major flood of the regional center Sizhou and Pan's dismissal from court. Subsequently, the river's 1680 flood entirely submerged Sizhou and the nearby Ming Zuling tombs beneath Hongze Lake for centuries until modern irrigation and flood control lowered

7326-566: The river repeatedly broke its levees and migrated north and west, officials battled over whether expensive measures should be taken to return the river to its former channels. The Shenzong emperor ultimately decreed that the river be allowed to remain in its new course. Traditional flood control techniques made use of levees , revetments to absorb the energy of the water, overflow basins, drainage canals and polders . Treatises on traditional flood control techniques were written by officials such as Pan Jixun , who argued that joining branches of

7425-693: The river skirts through the high-altitude peat bog known as the Zoigê Wetlands and makes a sharp turn towards the northwest forming the border between Maqu and Zoigê County in Sichuan . Flowing now along the northern edge of Amne Machin, the river reenters Qinghai and gradually curves north towards the Longyang Gorge at Xinghai . The valley section stretches from Longyang Gorge in Qinghai to Qingtong Gorge in Gansu. Steep cliffs line both sides of

7524-501: The river. The water bed is narrow and the average drop is large, so the flow in this section is extremely turbulent and fast. There are 20 gorges in this section, the most famous of these being the Longyang , Jishi, Liujia , Bapan, and Qingtong gorges. The flow conditions in this section makes it the best location for hydroelectric plants. The Yellow River exits Qinghai for the second and final time in these gorges and enters Gansu for

7623-423: The riverbed which flows between natural levees in its lower reaches. Should a flood occur, the river may break out of the levees into the surrounding lower flood plain and take a new channel. Historically this has occurred about once every hundred years. In modern times, considerable effort has been made to strengthen levees and control floods. Below is an incomplete list of hydroelectric power stations built on

7722-837: The sea. Since 2003, China has been working on the South–North Water Transfer Project to alleviate the strain on the river's water supply. When the Yellow River was still somewhat clear, it was simply referred to as 'the river' ( 河 , Old Chinese : *gâi ). Observations made at the Yumenkou gorge, where the river leaves the modern Loess Plateau , indicated the river changed to muddy sometime between 367 BC and 165 AD, according to chronicles' records. The alternative names 'murky river' ( 濁河 , *drôk-gâi ) and '(muddy) yellow river' ( 黃河 , *gwâŋ-gâi ) were attested in 145 BC and in 429 AD respectively. The name Yellow River fully replaces Murky River by

7821-491: The sea. The low volume is due to increased agricultural irrigation, increased by a factor of five since 1950. Water diverted from the river as of 1999 served 140 million people and irrigated 74,000 km (29,000 sq mi) of land. The Yellow River delta totals 8,000 square kilometers (3,100 square miles). However, with the decrease in silt reaching the sea, it has been reported to be shrinking slightly each year since 1996 through erosion. The highest volume occurs during

7920-592: The second time just before Liujia Gorge. Downstream from the Yanguo Gorge, the provincial capital of Lanzhou is built upon the Yellow River's banks. The Yellow River flows northeasterly out of Gansu and into Ningxia before the Qingtong Gorge. After emerging from the Qingtong Gorge, the river comes into a section of vast alluvial plains , the Yinchuan Plain and Hetao Plain . In this section,

8019-468: The slope gradient and high relief. When the water flows through the valleys and unstable rocky slopes, many clastic materials are washed away by the water. The removed materials are transported by the water and deposited in mountain foot and lowland basins. This may even form alluvial fans. There is a huge alluvial fan at the mountain foot of the Gobi Altay Mts. Therefore, the sediments and sands of

8118-490: The southeast during glacial periods . Therefore, the distance between the source areas and the Loess Plateau changes a lot. The grain size will increase in some northwest areas during glacial periods, even though the wind intensity does not change. This may also be associated with the transporting winds. During glacial periods, the Siberian High is enhanced, and the winter monsoon become drier and stronger. Therefore,

8217-554: The southern bank of the Yellow River, but did not stop them from reaching their goal of capturing Wuhan , which was the temporary seat of the Chinese government and straddles the Yangtze River . In 1954, the People's Republic of China announced its General Plan to Fundamentally Control Yellow River Flood Disasters and Develop Yellow River Waterworks. It sought to address both flooding risks and to convert rainfall-fed fields of

8316-584: The southern dikes of the Yellow River in an effort to stop the advancing Jin army. The resulting major river avulsion allowed the Yellow to capture the Si and other tributaries of the Huai River . For the first time in recorded history, the Yellow River shifted completely south of Shandong Peninsula and flowed into the Yellow Sea . By 1194, the mouth of the Huai had been blocked. The buildup of silt deposits

8415-614: The tectonic movement in the Neogene period, after which strong southeast winds caused by the East Asian Monsoon transported sediment to the plateau during the Quaternary period. The three main morphological types in the Loess Plateau are loess platforms, ridges and hills, formed by the deposition and erosion of loess. Most of the loess comes from the Gobi Desert and other nearby deserts. The sediments were transported to

8514-468: The thickness and the size of loess decrease from northwest to southeast. The figure shows the topography of the Chinese Loess Plateau. The loess near the Liu-p’an Mts is the thickest which is around 200 to 300 metres (660 to 980 ft) while the loess near the Yellow River is around 100 metres (330 ft) thick. This is related to the sorting by wind. When the monsoon wind and dust storm are blown from

8613-693: The three stages are divided. This article mainly adopts the division used by the Yellow River Conservancy Commission . The Yellow River derived sediments have been transported out of the Bohai Sea, all way to the North Yellow Sea and South Yellow Sea, and formed a Distal Depocenter around the Shandong Peninsula. The upper reaches of the Yellow River constitute a segment starting from its source in

8712-419: The top and edge of the slope or landslides and mostly in open shape and with little displacement. Sliding joints are in the body of landslides. Usually they are step-shaped and with large displacement. Collapsible joints are formed when there is asymmetrical settlement during rainfall or irrigation. They are located far from the edge of tableland and with apparent displacement. The lateral development of

8811-649: The two largest plateau freshwater lakes nationwide. A significant amount of land in the Yellow River's source area has been designated as the Sanjiangyuan ("'Three Rivers' Sources") National Nature Reserve , to protect the source region of the Yellow River, the Yangtze , and the Mekong . Flowing east at the eastern edge of the Amne Machin Mountains, the Yellow River enters Maqu County in Gansu . Here,

8910-415: The vertical loess joints can be divided into four stages. In the development stage original vertical joints, unloading joints and weathering joints can be found. In this range, the joints are mainly weathering joints and unloading joints. Nothing fill in the joint surfaces. In the micro-development stage, the distribution of the loess joints is sparser. The joints are filling with fine sand. This indicates

9009-506: The water level enough to permit their excavation and the tombs' restoration. Between 1851 and 1855 , the Yellow River returned to the north amid the floods that provoked the Nien and Taiping Rebellions . The 1887 flood has been estimated to have killed between 900,000 and 2 million people, and is the second-worst natural disaster in history (excluding famines and epidemics). The Yellow River more or less adopted its present course during

9108-404: The wind in Quaternary and modern wind. The results show that the wind direction in winter and spring-storm events are the same as the orientation of the bedrock ridges. Therefore, modern windstorms also contribute to shaping the eolian geomorphology. The Yellow River has provided sediments supply continuously which has been reworked by wind. Also, the wind erosion becomes stronger when it reaches

9207-407: Was formed before the loess deposition and it caused the different properties of the loess in different sides of the mountain. Most of the loess is deposited and well preserved at "Yuans", which are very flat. Some studies found that the apparent sedimentation rate, which determines the changes of the rate of deposition , has similar changes as the grain size changes. When the grain size increases,

9306-505: Was man-made, caused by the attempt of the Ming governor of Kaifeng to use the river to destroy the peasant rebels under Li Zicheng who had been besieging the city for the past six months. He directed his men to break the dikes in an attempt to flood the rebels, but destroyed his own city instead: the flood and the ensuing famine and plague are estimated to have killed 300,000 of the city's previous population of 378,000. The once-prosperous city

9405-477: Was merged into Mengjin District. This Henan location article is a stub . You can help Misplaced Pages by expanding it . Yellow River The Yellow River is the second-longest river in China and the sixth-longest river system on Earth, with an estimated length of 5,464 km (3,395 mi) and a watershed of 795,000 km (307,000 sq mi). Beginning in the Bayan Har Mountains ,

9504-521: Was nearly abandoned until its rebuilding under the Kangxi Emperor in the Qing dynasty . The question of how aggressively flooding should be controlled, and whether it should be steered back to its original channels when it migrated, was a topic of controversy in the imperial court. Rival cliques made arguments based on budgetary, technical and strategic criteria. Geographer Charles Greer identifies two competing schools of thought on how to control

9603-510: Was only in later times that the character 盟 was mistakenly replaced by 孟 . The ferry crossing was an important strategic location during times of war. In Chapter 6 of Romance of the Three Kingdoms , Cao Cao explains that part of his strategy in engaging Dong Zhuo 's forces was for Yuan Shao 's forces to take control of Mengjin (see: Battle of Xingyang ). As of 2012, Mengjin is divided to 10 towns. In March 2021, Jili District

9702-513: Was reduced, with the major fortifications and military bases moved upriver to Tongguan . In AD 923, the desperate Later Liang general Duan Ning again broke the dikes, flooding 1,000 square miles (2,600 km ) in a failed attempt to protect his realm's capital from the Later Tang . A similar proposal from the Song engineer Li Chun concerning flooding the lower reaches of the river to protect

9801-462: Was such that even after the Yellow River later shifted its course, the Huai could no longer flow along its historic course, but instead, its water pools into Hongze Lake and then runs southward toward the Yangtze River . A flood in 1344 returned the Yellow River south of Shandong. The Yuan dynasty was waning, and the emperor forced enormous teams to build new embankments for the river. The terrible conditions helped to fuel rebellions that led to

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