The riverbed of Tongtian River is 3000 ~ 4000 meters above sea level. The upper part of the valley is open, the river is wide and shallow, and there are rows of sandbars in the river, and the water flow is loose. The banks are not high mountains, but relatively gentle hills. After crossing the Chumar estuary, the mountains on both sides of the river gradually approached the river bank. The mountain on the left bank belongs to the famous Bayan Kara. Over this mountain is the source of the Yellow River, the second longest river in China. The lower section of Tongtian River is relatively straight, the river is gradually stable, the water gradient is increased, the water potential is turbulent, the mountains on both sides are increased, and the elevation of the valley bottom is reduced from more than 4,000 meters upstream to more than 3,000 meters. It is a typical canyon river.

Tongtian River flows through the extremely cold climate zone. Except for the eastern edge of the plateau, most areas are windy, with low temperature and thin air, with great vertical difference. The average temperature for many years is below 0℃. In the lower valley areas, the climate is mild and humid. There are phyllite, granite, gneiss, hard sandstone and mica schist in basin geology, and red sandstone and limestone in Tanggula rock phase.

Tongtian River, from the junction of Chumar River to the junction of Deng 'ailongqu, is a transition zone from hilly area of high plains to alpine valley area, with wide river valley and developed terraces. From the junction of Deng Ailongqu to the junction of the three provinces, it is an alpine canyon area. The mountains on both sides are steep and the water depth is swift. There are many big bends and small bends along the way, as if reluctant to miss the snowy mountain glacier that gave birth to her and raised her. There are Julia Bend, Gangcha Bend, Jumuqi Bend, Brown Bend and Landa Bend. There are big and small bends. Its majestic momentum and magnificent scenery are amazing, and its winding all the way is amazing. This winding river near the ring is called meandering or snake. The S-shaped bend in Tongtianhe is very similar to the Taiji diagram in the Eight Diagrams. This S-shaped bend is a special form of "snake bend"-"snake-embedded bend". Generally speaking, "snake bend" can only be formed in plains or wide valleys composed of loose sediments, and it is difficult to develop in rocks, because "concave bank erosion and convex bank accumulation" are difficult to occur on rocks. The uplift of the earth's crust is an important reason for this "embedded serpentine bend". Generally speaking, a river first forms a "serpentine bend" in the plains and basins composed of loose sediments, and then encounters the continuous uplift of the earth's crust, which gives the river the power to cut, while the flow of the river has been bound in the earlier "serpentine bend", so the river keeps its original "serpentine bend" shape and keeps cutting until it deeply cuts into the lithosphere of the earth's crust, which seems to be "embedded". Tongtianhe's Snake Song not only has the scientific value of geoscience research, but also has the aesthetic value in the form of Snake Song. Tongtian River is the source of the Yangtze River. Near the Tongtian River, it is also the source of the Yellow River and Lancang River, and is called the "Three Rivers Source". It is 278 kilometers long from Nangji Balong to the mouth of Chumar River, which is called the upper section of Tongtian River and belongs to the source area. It is 550 kilometers long from the mouth of Chumar River to the mouth of Batang River, which is called the lower section of Tongtian River and does not belong to the source area. In order to protect the ecological environment in this area, the state has established the "Sanjiangyuan Nature Reserve". The source of the Yangtze River is the region with the most remarkable biodiversity characteristics at high altitude in the world, and it is known as the natural germplasm resource pool of alpine organisms. Sanjiangyuan region has a unique and typical alpine ecosystem, which is a typical representative of the alpine environment in Central Asia Plateau and the alpine grassland in the world. Vegetation types include coniferous forest, broad-leaved forest, mixed coniferous and broad-leaved forest, shrub, meadow, grassland, swamp and aquatic vegetation, cushion vegetation and sparse vegetation, which can be divided into 14 formations and 50 formations. There are three kinds of national second-class protected plants, namely Picea crassifolia, Meconopsis rubra and Cordyceps sinensis, and 3 1 species of Orchidaceae listed in Appendix II of the International Trade Convention. There are 34 species of provincial key protected plants in Qinghai Province. There are 85 species of wild animals, 237 species of birds (including 263 subspecies) and 48 species of amphibians and reptiles. There are 69 species of national key protected animals, including Tibetan antelope, wild yak, snow leopard 16, and 35 species of blue sheep and Tibetan gazelle.

Most of the mountains, terraces and beaches on both sides of the main and tributaries of Tongtian River are covered with dwarf forests and turf, while the vegetation on both sides of the lower section is dense, trees and forests gradually appear, and the economy has changed from pure animal husbandry to agriculture and animal husbandry. Cold-tolerant crops such as highland barley can be planted in terraced fields and tributary valleys on both sides of the river. Yushu and Yudu counties have farmland 1.4 million mu, and Gangsang Temple and Zhimenda terraces grow highland barley, wheat, rape, Chinese cabbage and radish.

Most of Tongtianhe River Basin is located in Yushu Tibetan Autonomous Prefecture, Qinghai Province, at the source of Sanjiang River in the hinterland of Qinghai-Tibet Plateau in the southwest of Qinghai Province, with an average elevation of more than 4,200 meters. Yushu Tibetan means "site". It is connected with Haixi Mongolian and Tibetan Autonomous Prefecture in the north, Bayinguoleng Autonomous Prefecture in Xinjiang in the northwest, Guoluo Tibetan Autonomous Prefecture in the east, Ganzi Tibetan Autonomous Prefecture in Sichuan Province in the southeast and Qamdo and Naqu areas in Tibet in the southwest. It governs six counties, namely Yushu, Chengduo, Nangqian, Zaduo, Zhiduo and Qumalai, with a total population of 283 1 10,000, including 269,800 Tibetans, accounting for 95.3% of the total population.

Yushu Prefecture, founded in195165438+February, is the first minority autonomous prefecture in Qinghai Province and the second in China. Yushu cultivated land for Xiqiang yak in ancient times; Before and after the Sui Dynasty, Su Pi and Mi Duo were under the jurisdiction of two countries, Sun Boru of Tubo in the Tang Dynasty, the land of Nangqian Xiaozhou under Lizhou in the Song Dynasty, and Xuanwei Department of Tubo in the Yuan Dynasty. In the Ming Dynasty, a monk with five rooms in Nangqian was awarded the title of "freely proclaiming Buddhism" for many times. In the late Ming and early Qing dynasties, the heads of Yushu ministries named Qinghai, Mongolia and Huoshuo as all kinds of Tai Chi. Under the direct jurisdiction of the Minister of Qinghai Affairs, the Qing Dynasty was a territory with hundreds of independent tribes. During the Republic of China, Yushu, Nangqian and Yudu counties were established, which were under the administration supervision department of Yushu, and the system of thousands of households below the county level remained unchanged. 1949 10 the office of the military and political commission of Qinghai people's liberation army in Yushu was established, announcing that Yushu area has been completely managed by the people's government. 195 1 12.25 Yushu Tibetan Autonomous Prefecture was established, and 1955 was changed to an autonomous prefecture. The capital of the Autonomous Prefecture is located in Jiegu Town, Yushu City, which is the political, economic, cultural and transportation center of the whole state.

Yushu is known as "the source of rivers, the ancestor of famous mountains, the hometown of yaks, the hometown of singing and dancing", "the ancient road of Tang and Fan" and "the water tower of China". The Yangtze River, the Yellow River, the mother river of the Chinese nation, and the Mekong River, the largest giant river in Southeast Asia, all originated in Yushu. Yushu is an important part of the Qinghai-Tibet Plateau, forming a self-contained natural region in the hinterland of the Qinghai-Tibet Plateau. The Xuefeng Glacier, dominated by the main peak of Tanggula Mountain, has bred three famous rivers in China, such as the Yellow River and Lancang River, headed by the Yangtze River.

Among the 30 ethnic autonomous prefectures in China, it has the highest proportion of main ethnic groups, the highest altitude, the largest per capita area and the most important ecological status. The Yangtze River, the Yellow River and the Lancang River all originate locally. Sanjiangyuan Nature Reserve and Hoh Xil Nature Reserve cover the whole autonomous prefecture and are known as the source of rivers, the hometown of famous mountains, the hometown of yaks, the hometown of singing and dancing, and the Chinese water tower. Jiegu Town, the capital of the Autonomous Prefecture, is an important town of the ancient Tang-Fan Road in history, and also a non-governmental trade distribution center at the junction of Qinghai, Sichuan and Tibet.

Yushu Prefecture is an area with animal husbandry as the main part and agriculture and animal husbandry as the sideline. The average elevation of the whole territory is above 4000 meters. The annual rainfall is about 520 mm. The average annual temperature is 0.0 degrees Celsius. The oxygen content of air is only 40 ~ 60% of sea level. The existing grassland is 2 1 10,000 mu, of which grassland10.70 million mu can be used, with an annual output of 26,500 tons of fresh milk, 45,000 tons of beef and mutton, 0.3 million tons of wool/kloc-0.3 million tons and 900,000 pieces of cattle and sheep skins. The cultivated land is 267,000 mu, mainly planting highland barley, peas, potatoes, rape and taro. There are 26/kloc-0 kinds of minerals, including more than 40 kinds of gold, silver, copper, iron, aluminum, coal, sulfur, crystal and jade, with a total reserve of 30 billion tons. 9 13 kinds of Chinese herbal medicines have been identified, including 808 kinds of plants, including Cordyceps sinensis, Anemarrhena asphodeloides, Fritillaria, rhubarb and Saussurea involucrata. There are 80 kinds of animal medicines, mainly pilose antler and musk. The territory is rich in water resources, with three tributaries criss-crossing and dotted with lakes, with a total drainage area of 237,000 square kilometers, accounting for 89% of the total area of the state. The theoretical reserve of hydropower generation is 610.2 million kilowatts. There are four natural forest areas in Quanzhou with a total area of 390,000 hectares and a forest coverage rate of 2. 1%. In the mountain jungle Yuan Ye, there are all kinds of rare birds and animals, mainly including wild yak, wild donkey, Tibetan antelope, rock sheep, antelope, white-lipped deer, red deer, leopard, snow leopard, lynx, brown bear, black-necked crane, pheasant, snow chicken and other rare birds. The species of birds ranks first in the province, and the species of mammals ranks second in the province.

Yushu has many natural landscapes with plateau characteristics: there are famous Yushu songs and dances in Tibetan areas and mysterious Tang-Fan ancient roads; There are famous Princess Wencheng Temple and Tibetan Buddhist temples of many sects. There are the world's best Mana stone pile in the new village of Ghana and the 25-meter-high bronze statue of Zong Kaba sitting in Gangcha Temple; There are Longbaotan National Nature Reserve, the hometown of black-necked cranes, and Hoh Xil Wildlife Reserve, which are relatively intact. Quanzhou has more than 40 scenic spots.