Brahmaputra River – Trade, Irrigation, Flooding | Britannica

Brahmaputra River, a large river in Central and South Asia. It flows approximately 1,800 miles (2,900 kilometres) from its source in the Himalayas to its confluence with the Ganges (Ganga) River, where the combined waters of the two rivers pour into the Bay of Bengal.

The Brahmaputra flows through the Tibetan Autonomous Region of China, the Indian states of Arunachal Pradesh and Assam, and Bangladesh. For the majority of its length, the river functions as an important interior waterway. However, it is not navigable between the Tibetan mountains and the Indian plains. In its lower course, the river is both a creator and a destroyer, depositing vast amounts of fertile alluvial soil while also causing destructive and regular floods.

Physical features

Physiography

The Chemayungdung Glacier, which covers the Himalayan slopes about 60 miles (100 km) southeast of Lake Mapam in southwestern Tibet, serves as the source of the Brahmaputra. The three headstreams that emerge there are the Kubi, Angsi, and Chemayungdung. From its source, the river flows about 700 miles (1,100 kilometres) eastward between the Great Himalayas to the south and the Kailas Range to the north. Throughout its upper course, the river is commonly referred to as the Tsangpo (“Purifier”); it is also known by its Chinese name (Yarlung Zangbo) and various local Tibetan names.

In Tibet, the Tsangpo receives numerous tributaries. The Raka Zangbo (Raka Tsangpo) is the most major left-bank tributary, joining the river west of Xigazê (Shigatse), while the Lhasa (Kyi) flows past the Tibetan capital of Lhasa and joins the Tsangpo at Qüxü. The Nyang Qu (Gyamda) River flows into the river from the north at Zela (Tsela Dzong). A second river, the Nyang Qu (Nyang Chu), meets the Tsangpo at Xigazê.

After passing through Pi (Pe) in Tibet, the river abruptly turns north and northeast and flows through a series of enormous tight gorges between the steep massifs of Gyala Peri and Namjagbarwa (Namcha Barwa) in a series of rapids and cascades. The river then turns south and southwest, flowing through a steep gorge (the “Grand Canyon” of the Tsangpo) across the eastern tip of the Himalayas, with canyon walls extending upward for 16,500 feet (5,000 metres) or more on each side. During that section, the river enters northern Arunachal Pradesh state in northeastern India, where it is known as the Dihang (or Siang) River, and then swings southward.

The Dihang emerges from the highlands, bends southeast, and drops into a low-lying basin as it enters northeastern Assam. Just west of Sadiya, the river bends southwest and joins two mountain streams, the Lohit and the Dibang. Below that confluence, around 900 miles (1,450 kilometres) from the Bay of Bengal, the river is commonly referred to as the Brahmaputra (“Son of Brahma”. Even in the dry season, the river in Assam is strong, and during the rains, its banks are more than 5 miles (8 km) apart. Several quickly running Himalayan streams, including the Subansiri, Kameng, Bhareli, Dhansiri, Manas, Champamati, Saralbhanga, and Sankosh, join the river as it winds its way through the valley for 450 miles (700 kilometres). The primary tributaries from the hills and plateau to the south are the Burhi Dihing, Disang, Dikhu, and Kopili.

The Brahmaputra enters Bangladesh’s lowlands after turning south around the Garo Hills below Dhuburi, India. After passing through Chilmari, Bangladesh, it is joined on its right bank by the Tista River before continuing 150 miles (240 km) south as the Jamuna River. (South of Gaibanda, the Old Brahmaputra exits the left bank of the main stream and runs past Jamalpur and Mymensingh before joining the Meghna River at Bhairab Bazar.) Before confluence with the Ganges, the Jamuna receives the combined waters of the Baral, Atrai, and Hurasagar rivers on its right bank and becomes the point of departure for the massive Dhaleswari River on its left. The Buriganga (“Old Ganges”) is a tributary of the Dhaleswari that flows past Bangladesh’s capital, Dhaka, before joining the Meghna River above Munshiganj.

Climate

The temperature in the Brahmaputra valley differs from that of Tibet, which is severe, cold, and dry, to Bangladesh and Assam, which are both generally hot and humid. Tibetan summers are pleasant and bright, but winters are bitterly cold, with average lows of less than 32 °F (0 °C). Because the upper river valley is under the Himalayan rain shadow, Lhasa experiences very little yearly precipitation—roughly 16 inches (400 mm)—there.

The monsoon (wet, dry) climate, which is typical of the subcontinent, governs the Indian and Bangladeshi portions of the valley, albeit with some modifications from other regions. The average annual temperature in Dhaka is 29 °C (79 °F), while the hot season is shorter than usual. Throughout the year, there is a lot of humidity and comparatively substantial precipitation. The annual rainfall, which ranges from 70 to 150 inches (1,780 to 3,810 mm), primarily occurs between June and early October, however there are also occasional light showers from March through May.

Hydrology

Over time, the Brahmaputra’s path has seen multiple changes. The most notable of these modifications was the Tista River’s eastward diversion, which happened in 1787 during an extraordinarily high Tista flood, and the subsequent creation of the new Jamuna channel. The Tista’s waters abruptly changed course and joined the Brahmaputra across from Bahadurabad Ghat in the Mymensingh district, following an old, abandoned channel. The current Old Brahmaputra channel was once the course of the Brahmaputra, which flowed past the town of Mymensingh and entered the Meghna River near Bhairab Bazar until the late 18th century.

At the period, the route of today’s Jamuna River was followed by a tiny stream known as the Konai-Jenai, which was most likely a spill channel of the Old Brahmaputra. Following the Tista flood of 1787, the Brahmaputra began to cut a new route along the Konai-Jenai, gradually converting it around 1810 into the main stream, today known as the Jamuna.

Plant and animal life

The vegetation along the higher reaches of the Brahmaputra (Tsangpo) on Tibet’s high plateau is primarily xerophytic (drought-resistant) shrubs and grasses. As the river descends from Tibet, increasing precipitation promotes forest development. Assam has forests of sal (genus Shorea), a valuable wood tree that is also used to cultivate the lac bug, which generates the resin needed in shellac production. Tall reed jungles grow much lower in the swamps and depressed water-filled areas (jheels) of the vast floodplains.

Many fruit trees grow in the Assam Valley’s cities and villages, producing plantains, papayas, mangoes, and jackfruit. Bamboo thickets exist in Assam and Bangladesh. Nipa palms (Nypa fruticans) and other halophytic (salt-tolerant) vegetation are common in the delta region’s mangrove swamps.

The most notable animal in Assam’s swamps is the one-horned rhinoceros, which has become extinct in other parts of the world; Kaziranga National Park (designated a UNESCO World Heritage site in 1985) provides a refuge for the rhinoceros as well as other wildlife in the valley, including elephants, Bengal tigers, leopards, wild buffalo, and deer. Fish species include the pabda (Omdok pabda), chital (Notopterus chitala), and mrigal (Cirrhinus cirrhosus).

People

The people of the Brahmaputra valley come from a variety of backgrounds and cultures. Tibetans practise Buddhism and speak Tibetan. They raise livestock and cultivate the valley using river water for irrigation.

The Assamese are descended from people who spoke Tibeto-Burman languages in the surrounding highlands, as well as those from India’s lowlands to the south and west. Assamese is similar to Bengali, a language used in India’s West Bengal state and Bangladesh. Since the late nineteenth century, a large number of immigrants from Bangladesh’s Bengal Plain have entered Assam, settling to cultivate unoccupied lands, notably low floodplains.

In the Bengal Plain, the river flows through an area largely populated by Bengalis who cultivate the lush valley. The hilly borders of the plain are populated by the tribal Garo, Khasi, and Hajong of Meghalaya, India.

Economy of the Brahmaputra River

Irrigation and flood control

Flood control techniques and embankment construction began after 1954. In Bangladesh, the Brahmaputra embankment, which runs west of the Jamuna River from north to south, aids in flood management. The Tista Barrage Project serves two purposes: irrigation and flood control.

Until the 21st century, little power was harnessed along the Brahmaputra, despite the estimated potential of 12,000 megawatts in India alone. Assam has seen an increase in the number of hydroelectric plants completed, the most notable of which is the Kopili Hydel Project in the state’s south. Another big project, the Ranganadi plant in Arunachal Pradesh, has a much higher producing capacity than the Kopili station. In addition, a massive hydroelectric plant on Tibet’s Tsangpo River become fully operational in late 2015.

Navigation and transport

Near Lhazê (Lhatse Dzong), Tibet, the river becomes navigable for around 400 miles (640 kilometres). Coracles (boats made of hides and bamboo) and big ferries navigate its waters at 13,000 feet (4,000 metres) above sea level. Several suspension bridges span the Tsangpo.

Because it flows through a heavily rainy region in Assam and Bangladesh, the Brahmaputra is more significant for inland shipping than irrigation. The river has traditionally served as a waterway connecting the Indian states of West Bengal and Assam, while political disputes have occasionally hindered commerce flow through Bangladesh. The Brahmaputra is navigable throughout the Bengal Plain and Assam, up to Dibrugarh, 700 miles (1,100 kilometres) from the sea. In addition to all forms of local vessels, powered launches and steamers may readily go up and down the river, transporting bulky raw materials, lumber, and crude oil.

Study and exploration

The upper course of the Brahmaputra was surveyed as early as the 18th century, although it remained largely unknown until the nineteenth century. The explorations of the Indian surveyor Kinthup (reported in 1884) and J.F. Needham in Assam in 1886 established the Tsangpo River as the Brahmaputra’s upper channel. During the first quarter of the twentieth century, several British expeditions studied the Tsangpo upstream in Tibet to Xigazê, as well as the river’s mountain gorges. Recent scientific research has focused on studying the hydrology of the Brahmaputra for watershed management and flood risk prevention.

Final Word,We hope that this post helped you in finding the information about latest Brahmaputra River If you liked this article, then please share to social networking site and your friend thanks for visiting Job Rajasthan.com

Leave a Comment