The largest river in China, originating in the southeast of Gladang, the main peak of Tanggula on the Qinghai-Tibet Plateau, winds eastward from the Qinghai-Tibet Plateau, flows through Qinghai, Xizang Autonomous Region, Sichuan, Yunnan, Hubei, Hunan, Jiangxi, Anhui, Jiangsu, Shanghai and other provinces, autonomous regions and municipalities directly under the Central Government 10, and flows into the East China Sea in Shanghai, with a total length of 6,300 kilometers and a drainage area of 654,300.
Since ancient times, there have been different opinions about the source of the Yangtze River. In some modern geographical works, there are two opinions about the source of the Yangtze River: one is that "rivers originate from the same mountain", both the Yangtze River and the Yellow River originate from Bayan Kara, the Yangtze River originates from the southern foot and the Yellow River originates from the northern foot. The other is that the Yangtze River originates from Mount Kekexili. There are two sources: Murusu River in the south, Chumar River in the north, and Chumar River in summer. The Yangtze River Basin Planning Office organized Jiangyuan investigation teams twice, and conducted detailed field investigations in Jiangyuan area, finding out the Jiangyuan water system and its source .10005.10001000000006 The upper reaches of the Yangtze River are located between Kunlun Mountain and Tanggula Mountain, and there are many rivers, among which the largest are Chuma River, Tuotuo River and Dangqu River. According to the principle that "the source of the river is only far away", Tuotuo River is determined as the positive source. There is Dangqu River in the south and Dangqu River in the north. There are more than 40 snow-capped mountains above 6000 meters above sea level. The temperature is low and the four seasons are like winter. The annual precipitation is 200-400 mm, and snowfall is the main factor. The average temperature in July is below 0℃, and it can only reach above 0℃ under the strong radiation of the sun during the day, and the trickle formed by the melting of ice and snow becomes the initial water source of the Yangtze River.
From the source to the estuary, the mainstream Yangtze River crosses three huge steps of China's topography, passes through different geological structures and strata, and receives the inflow of tributaries along the way, which has different influences on the valley shape and flow characteristics of the Yangtze River. According to the hydrological and geomorphological characteristics, the main stream is divided into three sections: the upper reaches from Heyuan to Yichang, the middle reaches from Yichang to Hukou, and the lower reaches below Hukou.
① Upstream part. The upstream part spans two terrain steps. The total length is 4529 kilometers, accounting for 72.0% of the length of the Yangtze River. The basin area is10.006 million square kilometers, accounting for 55.6% of the basin area. Tuotuo Upstream and Tongtian River (from Nangji Balong to Batang Estuary) are very popular in the hinterland of Qinghai-Tibet Plateau. Because they are at the top of the plateau, the valley is open. The river is tortuous, the water flow is slow and scattered, and there are many tributaries. From Batang estuary to Yibin, it is called Jinsha River, which is the transition section from the first step to the second step. The terrain here is steep, with high mountains and deep valleys. Except for the wide river valley in some areas, the river runs through the canyon with a large slope and the river is swift. Below the stone drum in Yunnan, it suddenly turns to the northeast, and the famous Tiger Leaping Gorge is 35 kilometers below the stone drum. The canyon is very long. The narrowest part is only 30 meters. After leaving Tiger Leaping Gorge, cross the northern Yunnan-Guizhou Plateau and enter the second step below the new town in Sichuan Province. After the Minjiang River gathers near Yibin, it is called Yangtze River. The length from Yibin to Yichang is 1030 km, which is customarily called Chuanjiang. The river meanders in Sichuan Basin, with gentle riverbed, and accepts many tributaries such as Tuojiang River, Jialing River and Wujiang River along the way, and the water volume increases greatly. The transition section of the Yangtze River from the second step to the third step runs through three anticlines and two synclines in July, Wushan and Huangling, forming the world-famous Three Gorges of the Yangtze River (Qutang Gorge, Wuxia Gorge and Xiling Gorge), with a total length of about 200 kilometers, and canyons and wide valleys alternately arranged.
② Middle reaches. The Yangtze River flows from the Three Gorges below Yichang to the middle and lower reaches of the Yangtze River. The river surface is widened, the water flow is slow and the river course is curved. It is 927 kilometers long, accounting for 14.7% of the length of the Yangtze River. The basin covers an area of 679,000 square kilometers, accounting for 37.6% of the basin area. Among them, the section from Zhicheng in Hubei to Chenglingji in Hunan is about 420 kilometers long. Hence the name Jingjiang. Jingjiang River is divided into upper Jingjiang River (from Zhicheng to Ouchikou) and lower Jingjiang River (from Ouchikou to Chenglingji). The lower Jingjiang River twists and turns, known as the "nine-bend ileum". There are many lakes on both sides of the middle reaches, which are connected by rivers and lakes, forming two huge water systems, Dongting Lake and Poyang Lake. After the Yangtze River received water from two major river systems and tributaries directly flowing into the river, its water volume more than doubled. Under the entrance of the lake, it enters.
③ downstream section. The water depth is wide, and the length from the mouth of the lake to the mouth of the sea is 844 kilometers, accounting for 13.3% of the length of the Yangtze River. Watershed area123,000 square kilometers, accounting for 6.8% of the watershed area. The main stream of the Yangtze River in Yangzhou and Zhenjiang, Jiangsu Province is also called the Yangtze River. It is named after the Yangtze River in ancient times and Yangzi County today. Now the name of the Yangtze River is commonly used by foreigners. The average tidal current entering the Yangtze River estuary is 266,000 cubic meters per second, which is 8.8 times of the Yangtze River's average flow into the sea for many years. Under normal circumstances, the total tidal current is about 3.25 billion cubic meters at a time, and it can reach 4.5 billion cubic meters at high tide. Due to the backward flow of seawater, the flow speed of the river slows down, and the sediment carried by it is deposited in the downstream reach, especially near the estuary. So dozens of sandbars of different sizes have been formed in the middle of the river, the largest of which is the largest.
The flow fields of runoff resources and hydraulic resources are 24 27' ~ 35 54' north latitude and 90 33' ~12219' east longitude. Located in the East Asian monsoon region, except for a small part of the plateau cold climate, most areas have subtropical monsoon climate. There is abundant precipitation, and the average precipitation in the basin reaches 1057. Rainwater has become the main source of recharge for most rivers. Runoff mainly comes from upstream and middle reaches, accounting for 47. 1% and 47.2% respectively, while the downstream only accounts for 5.7%. The average annual runoff for many years is 975.5 billion cubic meters. The exploitable hydropower resources are about 1 0.97 billion kilowatts, and the annual power generation is about1trillion kilowatts, accounting for 50 trillion kilowatts of exploitable hydropower resources in China.
The main stream of the Yangtze River has a long history, with numerous tributaries and abundant water. It doesn't freeze all year round. The navigation mileage of the main stream is 70,000 kilometers, and the navigation channel available for motorboats is about 30,000 kilometers. The main stream of Yichang is a ship below 3000 kilometers, and a 10,000-ton seagoing ship can reach Nanjing directly. At the same time, the main stream is connected with the ocean, which not only facilitates the connection between the basin and the coastal areas, but also carries out economic and trade exchanges with foreign countries, so it is called the golden waterway.
Source: Gladandong Snow Mountain, Tanggula Mountain, Qinghai-Tibet Plateau. With a total length of 6380Km, it is the third largest river in the world and the largest river in China. World River Rankings: First, the Nile (Africa and Egypt); Second, the Amazon River (Brazil in South America); Three, the Yangtze River (Asia, China) covers an area of 6.5438+0.8 million square kilometers, ranking first in the country. It flows through nine provinces and two cities: (pointing to the map) Qinghai → Sichuan → Tibet → Yunnan → Chongqing → Hubei → Hunan → Anhui → Jiangxi → Jiangsu → Shanghai, and enters the East China Sea through Wusongkou, Shanghai.
The Yangtze River is the largest river in China, and it was called "Great River" in ancient times. It flows through Tibet, Sichuan, Yunnan, Hubei, Hunan, Jiangxi, Anhui, Jiangsu and other provinces, and flows into the East China Sea in Shanghai. There are 742 cities and counties in the basin, with a total population of nearly 400 million and a total area of 65.438+0.8 million square kilometers. There are Yalong River, Jiangsu River and Yalong River.
The Yangtze River and the Grand Canal intersect in Zhenjiang City, Jiangsu Province. Over Yichang City, Hubei Province, there are many rapids in the upper reaches. Yichang to Hukou in Jiangxi is the middle reaches, with meandering development and numerous lakes (Poyang Lake and Dongting are the largest). Below the mouth of the lake is Chongming Island, downstream and wide, which is impacted by the estuary.
The Yangtze River is rich in water and hydraulic resources. When there is plenty of water, a 10,000-ton boat can go to Wuhan and a boat can go back to Changyi. The important cities along the Yangtze River are Chongqing, Wuhan, Nanjing and Shanghai.
There are no fewer than 30 kinds of names and aliases for the main reaches of the Yangtze River. Yibin to Yichang, Hubei, because most of it flows through Sichuan Province, commonly known as Chuanjiang. The Yangtze River bends into several shapes near Jiangjin, Sichuan, also called Jijiang. The reach from Baidicheng, fengjie county, Sichuan Province to Yichang Three Gorges is commonly known as Xiajiang. Zhicheng, Hubei Province to Chenglingji, Yueyang City, Hunan Province, is commonly known as Jingjiang River because it flows through the ancient Jingzhou area. This section of the river twists and turns, known as Jiujiang.
Not long ago, scientists surveyed the Yangtze River again and found that its length was 62 1 1.3 kilometers, which was more than 80 kilometers shorter than the recognized 6300 kilometers. But this result has not changed the position of the Yangtze River as the longest river in Asia and the third longest river in the world. The length of the Yangtze River reach is as follows: Dangqu (from the source to Nangji Balong) is 360.8 kilometers, and Tuotuo is 357.6 kilometers.
With its rich resources, the Yangtze River waters the motherland and nurtures the children of all ethnic groups. With its vast river basin, the Yangtze River connects the majestic mountains in the west and the vast sea in the east. In the new era, the water of the Yangtze River has irrigated the more fertile land of the motherland and contributed to the promotion of the four modernizations with a brand-new attitude. Therefore, it can be said that the Yangtze River is an "infinite source" and "has the feelings of a mother".
The source of the upper reaches of the Yangtze River is detached, which originated from the Gladden Snow Mountain in Tanggula Mountain, the southwestern border of Qinghai, and was called Tongtianhe after the adjustment. From Batang estuary in Yushu county to Yibin city in Sichuan province, it is called Jinsha River. Yibin is called the Yangtze River and Yangzhou is called the Yangtze River. The Yangtze River flows through Tibet, Sichuan, Chongqing, Yunnan, Hubei, Hunan, Jiangxi, Anhui, Jiangsu and other provinces and cities and joins the East China Sea in Shanghai. There are tributaries such as Yalong River, Minjiang River, Tuojiang River, Jialing River, Wujiang River, Xiangjiang River, Hanjiang River, Ganjiang River, Qingyi River and Huangpu River. In Zhenjiang, Jiangsu.