Headwaters in Tibet
Basin of the Brahmaputra
The Brahmaputra is the main strand of the Meghna opens into the Indian Ocean water-rich stream in Asia. It flows with a length of approximately 3100 kilometers to the confluence with the Ganges through the territory of the countries China, India and Bangladesh. His run is partly variable and partly difficult to access and crosses several cultural regions, which has led to many different names for sections.
Name of the river sections
The east facing upper reaches of the Brahmaputra is called in Tibet in Tibetan Matsang or tachographs Tsangpo ( in Wylie transliteration: rta mchog gtsang po), in Chinese Mǎquán Hé马 泉河/马 泉河; then it is called in Tibetan Yarlung Tsangpo ཡར་ཀླུང་གཙང་པོ ( yar lopment gtsang po), the cleaning, according to another source " from the highest peak water coming down ," and in Chinese Yǎlǔ Zàngbù Jiang雅鲁藏布江/雅鲁藏布江.
In the Indian state of Arunachal Pradesh has the sharply bent to the south river the name Dihang or Siang. After a change of direction to the west at the mouth of the largest tributary, the Lohit, he is, now the state of Assam by fluent, Brahmaputra ( ब्रह्मपुत्र ), which in Sanskrit means " son of Brahma ". An older name of this section of the river was ( in Sanskrit writings and in parts of Assam ) Luit or Lohitya, as used to be considered as the upper reaches of the larger Dihang instead of Lohit. Today, the name in Hindi ब्रह्मपुत्र, Brahmaputra is spoken on ব্ৰহ্মপুত্ৰ Assamese and Bengali ব্রহ্মপুত্র Brohmoputro.
With a turn to the south of the river enters the territory of Bangladesh and partly leads from there, partly from the junction of the Old Brahmaputra (formerly the main stream ) the name Jamuna. From the meeting with the much less bulky transition of power swings in the south-east and is now called Padma until it changes its name from the mouth of the Meghna last major tributary to its mouth in the Bay of Bengal.
High valley of the Tsangpo
The Brahmaputra ( Tsangpo ) rises on the northern side of the central Himalaya 130 km east of the Gang Rinpoche ( Kailash ). After the union of three source streams whose mean and water- richest glacier Jema Yangdzom (Tibetan: rje ma g.yang ' dzoms ) pours, the river is called for the next 268 km Matsang. The river runs for a total of 2057 km within Tibet, mostly about 160 kilometers north parallel to the main line of the Himalayas in the east. His often rectilinear valley divides there, accompanied by major fault lines, the Himalayas to the south from the Trans Himalayas in the north. The intriguing and dry grasslands upper valley is wide over longer distances and settled, interrupted by narrow passages. The ramification flowing Tsangpo is about 650 river kilometers and running in more than 3650 meters above sea level the highest navigable waterway of the earth. Its average discharge is between good 900 m³ / s at Yangcun (near Lhasa ) and almost 2000 m³ / s at the beginning of the great canyons.
Canyons in Pemako
In the Dihangschluchten, called the upper part Yarlung Tsangpo Canyon, the river cuts through the mountains in the northeast first, then south. This 250 km long, up to 3000 meters deep gorge is on both sides of individual peaks around 5000 meters dominates ( Namjagbarwa, 7782 m, Gyala Peri, 7294 m) and is often considered the deepest gorge in the earth called. 1913 FM Bailey managed to prove that the Tsangpo forms the upper reaches of the Brahmaputra, and only in 1998 was the roughest section will reach there with multiple, up to 35 meters high waterfalls of the Tsangpo from one of the international expeditions. From the Tibetan them this holy Pemako said territory was long kept secret.
From the mouth of the river Tsangpo Parlung Dihang is called. Just a few hundred meters, the below the canyons in the state of Arunachal Pradesh narrow valley receives high monsoonal rainfall, but without a pronounced dry season, so the flow increases rapidly in water management and dense rain forest, the slopes are covered. For this transverse valley of the Siang ( Dihang ) occurs abruptly into the long-range Bengal lowland. His water supply in this case is almost 6000 m³ / s
Brahmaputra ( Jamuna ) in the lowlands of Bengal
The suddenly reduced gradient leaves the heavily sediment- laden river at the foot of the hills form a large, flat alluvial fan, about whom he in strongly interwoven run the deepest region of the plane of Assam reached and there on the western direction of flow of its largest tributary, the branches as far flowing Lohit, pivots. Together with the recently introduced culminated nearly uniform size Dibang leads the Lohit about 4000 m³ / s and thus increases the power by around 65 % now called Brahmaputra. In the course of the river bed reaches several times a width of almost 15 kilometers, which is, however, only completed in 3 months of the monsoon season entirely. Then, the flow can thus lead up to 55,500 m³ / s water at Pandu in Assam, as the minimum drain, however, is only just over 1000 m³ / s have been registered (Middle Rhine discharge: 2300 m³ / s).
In the course of the Brahmaputra flow in quick succession to water-rich tributaries, the southern edge of the Himalayas to rainfall from the hill country in the south ( Shillong Plateau ) exceeded. The town of Cherrapunji lying there became known by precipitation record levels. It is bordered in part, directly to the river, first at the Kaziranga National Park, then in the greatest city on its shores, Guwahati, where the narrowest one kilometer width instead of the Brahmaputra lies, and finally at the western foothills of the plateau, where the stream after turns south and reached Bangladesh.
Delta area and age Brahmaputra
Where from the west joins the Tista in the stream now called Jamuna, branches off to the east as a small arm of the Old Brahmaputra. The main flow keeps its interlaced nature and has a flow rate of an average of 21,200 m³ / s The catchment area comprises the Brahmaputra far 651,335 km ².
After the confluence with the main branch of the Ganges, also called Padma ( 11,400 m³ / s), the mighty current flows under this name to the southwest.
The lower section of the river reaches as Lower Meghna, divided into several estuaries, the Bay of Bengal. With an average water flow of 36,500 m³ / s, the power only from the Amazon and the Congo is exceeded. The total length of the river system is about 3350 km
Along with numerous branching off from the Ganges estuary of smaller forms the Lower Meghna großflächigste the estuary of the earth, known as the Ganges delta.
The Old Brahmaputra follows his former power gutters across the Dhaka Division, it flows through the city of Mymensingh and flows, divided into two branches, the one in the Upper Meghna, on the other hand in another branch of the Jamuna, the Dhaleshwari that with one of his side arms, the Buriganga, the capital of Bangladesh, Dhaka, touched.
Characteristics and development of the river system
The Brahmaputra is in its course much mapped out by tectonic processes and structures that has spawned with the Eurasian plate so far, the current collision process of the Indian plate.
The west east running Tsangpo records over long distances by the Erdnaht that separates the two plates. There is evidence that the eastern Tsangpo was until the Miocene of the upper reaches of the current flowing through Myanmar Irrawaddy. The deflection south to today's lowlands of Assam out was before the Himalayas lifted out strong; the transverse valley of Dihang transverse to the line highest peak of the Himalayas is therefore antecedent.
In the western valley of the Tsangpo lead many tributaries meet its flow direction is assumed that that this part of the valley originally drained to the west. The river would then be followed by a today only 75 meters higher pass away today's Kali Gandaki and might even have been the gigantic gorge created.
The rugged gorge of the Yarlung Tsangpo has been reshaped to a through opening out, especially ice-age glaciers, and on the other by repeated bursts of up to 680 meters deep Eisstauseen, which had formed in front of them and about 300 kilometers far ranged into Tibetan highlands. In addition to the Lößanwehungen the sediments of this Eisstauseen brought the fertile soil for today's " bread basket of Tibet " show.
Also in the mouth region tectonic uplift across much of the structure of the flow system. The one with the lower reaches of the Ganges united Brahmaputra, which is the biggest power in Asia exists, so only since the 18th century coming to an end. Previously led both streams separately into the Bay of Bengal, where the Brahmaputra to the east, along the present-day Old Brahmaputra was docked and the broad stream channels of today's Upper Meghna. The western shift to the present Jamuna running successes, especially since an earthquake in 1782. At the same time the western part of the Ganges Delta, what the Padma arm of the Ganges had become his dominant main current lifts.
Depending on the course of the estuaries of the Brahmaputra either as now, the main strand of the largest river system in Asia, or separated from the Ganges (but still einmündender Upper Meghna ), after the Yangtze River ( with 31,900 m³ / s ) is thus the second largest electricity with about 25,000 m³ / s
The river gradient of Dihangschluchten starts at around 3000 meters above sea level and ends at a short distance of only 300 meters. It represents one of the largest hydro-electric potential of the earth dar. In China there is therefore efforts, in the Yarlung Tsangpo changes in Medog ( Metog ) on the north- eastern point of the river loop around the Namjagbarwa / Namcha Barwa, its direction from northeast to southwest, a to build 160 -meter high dam for a hydroelectric power plant, which would be the largest of the earth with 26 turbines and a planned capacity of 40,000 MW. In China also feasibility studies are underway to drain water in the semi-arid north-east of the country. Since both projects can bring disadvantages for the downstream areas with it, this both increases the potential for conflict with India and Bangladesh.
Has long been attempting to regulate the lowland sections of the river by technical measures to make for commercial river traffic more usable. Because of great technical complexity, this is so far succeeded only very limited. Often the river creates during flooding new riverbeds and caused so much economic damage. In addition, a broadening tendency of the Jamuna bed is noted; from an average of 6.2 kilometers wide in 1830 to 10.6 km in 1992, which may be due to an increase in sediment transport.