Yellow River Information

The Yellow River is the second longest river in my country. It originates from the Bayan Har Mountains in Qinghai. Its main stream runs through nine provinces and autonomous regions, passing through Qinghai, Sichuan, Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi, Henan, and Shandong. , with a total length of 5,464 kilometers, a drainage area of ??750,000 square kilometers, an annual runoff of 57.4 billion cubic meters, and an average runoff depth of 79. However, the water volume is not as large as that of the Pearl River. There are 35 main tributaries along the river. The larger tributaries include Huangshui River and Tao River in the upper reaches, Qingshui River, Fen River, Wei River and Qin River in the middle reaches, and Yi River and Luo River in the lower reaches. There are no lakes on both sides of the river, the lower reaches of the Yellow River are very small, and there are very few rivers flowing into the Yellow River. The mouth of the Yellow River is 1,500 meters wide, usually 500 meters, and the narrower part is only 300 meters. The water depth is generally 2.5 meters, and in some places the depth is only 1.2 to 1.3 meters.

Geographical environment: From the source of the river to Guide, there are many mountains and grassland plateaus, which belong to the Qinghai-Tibet Plateau. The altitudes are all above 3,000 meters and the peaks are over 4,000 meters. The source valley is 4,200 meters above sea level. The terrain on both sides of the valley in the river source section is gentle. The drainage is poor, forming a large area of ??swampland with many lakes; the section from Guide to Mengjin is the Loess Plateau area. The Loess Plateau is Luliang Xibo, the Wei River Valley to the south, the Ordos Plateau to the north, and the Lanzhou Valley to the west; the Loess Plateau The altitude is generally 1000-1300 meters, the landform is undulating, steep slopes and deep ravines, the gully ground slope is 15-20 degrees, the gully area accounts for 40-50%, the channel density is 3-5 kilometers/square kilometers, the cutting depth is more than 100 meters; below Mengjin Entering the low-lying North China Plain, the altitude does not exceed 50 meters. After entering the lower reaches, the river course is flat, with an average specific drop of only 0.12. The water flow slows down and a large amount of sediment accumulates, 4-5 meters above the ground. Due to the multiple changes in the course of the Yellow River, the land area The fan-shaped ancient riverbed and ancient natural embankments have become sloping plains alternately distributed with gentle hills and depressions. The depressions are relatively open and flat.

Ecological Characteristics

There are 121 species (subspecies) of fish in the main stream of the Yellow River. Among the 98 species of pure freshwater fish in the main stream, they account for 78.4% of the total. The main economic fish are spotted carp, polar flat-toothed carp, thick-lipped carp, yellow river carps, Valsalva's yarrow, northern copper carp (pigeon fish), carp, and crucian carp. There are only 16 species of fish in the upper reaches of the Yellow River, and their composition is relatively simple, with only schizothorax, catfish, yarrow, and striped loach from the carp and loach families. The fish species in the middle and lower reaches are generally similar, with Cyprinidae being the main species. There are 71 species of fish in the middle reaches, but there are no natural fish species such as silver carp, bighead carp, bream, and bream. The upper reaches of the middle reaches have schizothorax and striped loach, which are unique to the upper reaches. The types and quantities of fish in the lower reaches are There are many species, with 78 species, including a variety of estuary fish and brackish water fish. According to the survey data of the tributaries of the Yellow River, according to the fish statistics of the Tao River in Gansu, the Wei River, and the Jing River in Shaanxi, the Wei River has more species in its waters, with 30 species, followed by the Tao River with 11 species, and the Jing River with only 4 species. kind. Most of the tributaries in the upper and middle reaches are small fishes of the family Cyprinidae and Loachidae, and there are also a few fishes of the family Cyprinidae and catfish. The economic fish are carp, crucian carp, yarrow and catfish.

Fishery production: The main types of fish caught in the Yellow River have also changed. Among the fish in the main stream, carp has the highest production in history. "Yellow River Carp" is famous in the country, but now the production has dropped significantly. Before the 1960s, carp accounted for 60 to 70% of the catch in the midstream Shaanxi-Jinxi River section, ranking first in the composition of the catch. According to a survey of the catch in the port section of the Yellow River in Shaanxi in 1981-82, changes in the catch over the past decade have Carp accounted for only 21% of the catch, while catfish took over the main position accounting for 41.1%, followed by yellow catfish accounting for 26.3%. A survey of fish catches in the main stream of the Yellow River in Pinglu County, Shanxi Province in 1983 showed that carp accounted for only 20% of the total, while catfish accounted for as much as 60%, becoming the main catch. In the downstream Shandong section, carp accounted for 50-70% of the total production in the early 1950s, but dropped to 15% in the 1960s. By 1981-82, according to surveys, it had dropped to only 7.1%.

The status of the fishery labor force in the eight provinces and districts along the main flow path of the Yellow River is as follows: Except for Qinghai Province, which has no statistics, the fishery professional fishing labor force in seven provinces and districts including Gansu, Ningxia, Inner Mongolia, Shanxi, Shaanxi, Henan, and Shandong was 26,964 in 1980. In 1983, it dropped to 11,320 people, accounting for 3.0% and 2.1% of the total labor force of the same type in the country; the part-time fishing labor force was 24,843 people in 1980, and increased to 25,873 people in 1983, accounting for 8.9% and 5.7 of the total labor force of the same type in the country, respectively. %. Over the past 30 years, the number of carp, the main economic fish in the catch of the Yellow River, has dropped significantly, and the composition of the catch group has also changed accordingly. In the early 1980s, a survey was conducted on the carp in the catch of the Tongguan Port section of the Yellow River. , most of them are 3-year-old individuals with an average weight of 0.7 kg per tail accounting for 44.7%, followed by 4-year-old individuals with an average weight of 1.5 kg accounting for 28.4%.

Main fishing methods: The fishing gear and fishing methods used in fishery production operations in the main stream of the Yellow River are mostly gillnets in the upper and middle reaches, and there are also ground pull nets. The gillnets are divided into single-layer and three-layer. Triple flow gill net is more efficient. In addition, there are many types of roller fishing, fishing hooks and clips, but there are only four or five types in the middle reaches.

Characteristics of the fishing area: 8 species of Schizothorax subfamily and Loach subfamily in the upper reaches, carp, crucian carp, and catfish in the middle reaches, and swordfish, common carp, grass carp, and catfish in the lower reaches.

Upstream: From the source of the river to Guide, there are many mountains and grassland plateaus on both sides of the river. The altitude is above 3,000 meters, and the peak can exceed 4,000 meters. Lakes, grasslands, swamps, and rivers have stable clear water flow, low water consumption and large water production. There are many lakes, the largest lakes are Xingxiu Sea and Eling Lake. The climate is cold on the plateau, and the fish species are Central Asian plateau flora. There are few species and rich resources. Fish resources have not been exploited for a long time.

Middle reaches: From Guide to Mengjin, there are multi-path alpine gorges with rapid water flow and large slopes. From Guide to Liujia Gorge, the valley is extremely deep. The river is 50-70 meters wide and the narrowest point is less than 15 meters. The depth of the valley is 100-500 meters, the water flow is rapid, the cliffs are narrow and steep, and it contains rich hydraulic resources. A large reservoir was built on the canyon. After the Yellow River leaves Qingtong Gorge and enters the Hetao, it forms a large alluvial plain with gentle water flow and abundant carp, crucian carp and catfish resources. Richer. The Yellow River flows through Hekou Town, turns south, and passes through the Qin and Jin Gorges. The total length to Longmen is only 718 kilometers, with a drop of 611 meters, which is larger than the drop. The 130-kilometer river section from Longmen to Tongguan, Nafen, Wei, Jing, and Luo The water volume has greatly increased, the sediment has accumulated in large quantities, the river channel is unstable, and carp resources are abundant. The middle reaches pass through the high loess slopes, carrying a large amount of sediment, causing great harm to the downstream, and it is a key river section to eradicate water damage.

Downstream: The section from Mengjin to the North China Plain is the downstream, with a total length of 874 kilometers. The river is wide and flat, with slow flow and siltation. The river bed is 4-5 meters above the ground on average. It is an above-ground river and has fish resources. The most abundant fishery reaches include estuarine migratory fish, channel fish, settled fish, brackish water fish and aquatic fish.

The upper reaches of the Yellow River from the source to Hekou Town, Tuoketuo County, Inner Mongolia Autonomous Region, is 3,472 kilometers long; the middle reaches from Hekou Town to Taohua Valley, Zhengzhou, Henan, is 1,206 kilometers long; the lower reaches below Taohua Valley are , the river is 786 kilometers long. (There are many opinions on the division of the upper, middle and lower reaches of the Yellow River. The division plan of the Yellow River Conservancy Commission is used here.) The Yellow River traverses China from east to west. The basin is 1,900 kilometers long from east to west and 1,100 kilometers wide from north to south, with a total area of ??752,443 square kilometers.

The Yellow River, like a lion with its back arched and head held high, crosses the mountains of Qinghai and Gansu Provinces from the Qinghai-Tibet Plateau; crosses the Hetao Plains of Ningxia and Inner Mongolia; and gallops between Shanxi and Shaanxi Among the high mountains and deep valleys; break through the "Dragon Gate", turn east at the foot of Huashan Mountain in Xiyue, cross the North China Plain, and rush to the coast of the Bohai Sea. It flows through 9 provinces and regions, gathering more than 40 main tributaries and more than 1,000 streams, with a journey of 5,464 kilometers and a drainage area of ??more than 750,000 square kilometers. It is the second largest river in China.

The average annual precipitation in the entire basin is about 400 mm, while the average annual runoff of the Yellow River is only 57.4 billion cubic meters, ranking eighth among Chinese rivers. Within the basin, together with the downstream Henan and Shandong riverside areas, there are more than 200 million acres of cultivated land and a population of about 100 million.

The annual average natural runoff of the entire Yellow River is 58 billion cubic meters, the average annual runoff depth in the basin is 77 mm, the per capita water volume in the basin is 593 cubic meters, and the average water volume per mu of cultivated land is 324 cubic meters.

The middle reaches of the Yellow River flows through the Loess Plateau, and its tributaries bring in large amounts of sediment, making the Yellow River the river with the most sediment in the world. The maximum annual sand transport volume reached 3.91 billion tons (1933), and the maximum sand content was 920 kg/cubic meter (1977). The annual average sediment transport volume of Sanmenxia Station is about 1.6 billion tons, and the average sediment content is 35 kg/cubic meter.

Information data

Length 5464 kilometers

Source altitude 4800 meters

Average flow 1774.5 cubic meters/second

The basin area is 752,443 square kilometers

The source is Qinghai Province

It flows into the Bohai Sea

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