Misplaced Pages

#575424

111-780: The Dihing or Burhi Dihing (Dihong = wide river) is a large tributary, about 380 kilometres (240 mi) long, of the Brahmaputra River in Upper Assam in northeastern India. The river originates at 2,375 metres (7,792 ft) above sea level in the Eastern Himalayas (the Patkai Hills) in Arunachal Pradesh and flows through Tinsukia and Dibrugarh Districts in Assam to its confluence with

222-540: A ball drive, gear drive, or impact mechanism. Rotors can be designed to rotate in a full or partial circle. Guns are similar to rotors, except that they generally operate at very high pressures of 275 to 900 kPa (40 to 130 psi) and flows of 3 to 76 L/s (50 to 1200 US gal/min), usually with nozzle diameters in the range of 10 to 50 mm (0.5 to 1.9 in). Guns are used not only for irrigation, but also for industrial applications such as dust suppression and logging . Sprinklers can also be mounted on moving platforms connected to

333-419: A circular or semi-circular pattern. Traveling Sprinklers: These move along the hose path on their own, watering as they go, ideal for covering long, narrow spaces. Each type offers different advantages based on garden size and shape, water pressure, and specific watering needs. Subirrigation has been used for many years in field crops in areas with high water tables . It is a method of artificially raising

444-589: A clock or timer. Most automatic systems employ electric solenoid valves . Each zone has one or more of these valves that are wired to the controller. When the controller sends power to the valve, the valve opens, allowing water to flow to the sprinklers in that zone. There are two main types of sprinklers used in lawn irrigation, pop-up spray heads and rotors. Spray heads have a fixed spray pattern, while rotors have one or more streams that rotate. Spray heads are used to cover smaller areas, while rotors are used for larger areas. Golf course rotors are sometimes so large that

555-426: A computerized set of valves . In sprinkler or overhead irrigation, water is piped to one or more central locations within the field and distributed by overhead high-pressure sprinklers or guns. A system using sprinklers, sprays, or guns mounted overhead on permanently installed risers is often referred to as a solid-set irrigation system. Higher pressure sprinklers that rotate are called rotors and are driven by

666-581: A deep gorge (the " Yarlung Tsangpo Grand Canyon ") across the eastern extremity of the Himalayas with canyon walls that extend upward for 5,000 m (16,000 ft) and more on each side. During that stretch, the river crosses the China-India line of actual control to enter northern Arunachal Pradesh, where it is known as the Dihang (or Siang) River, and turns more southerly. The Yarlung Tsangpo leaves

777-494: A direct financial cost to the farmer. Irrigation often requires pumping energy (either electricity or fossil fuel) to deliver water to the field or supply the correct operating pressure. Hence increased efficiency will reduce both the water cost and energy cost per unit of agricultural production. A reduction of water use on one field may mean that the farmer is able to irrigate a larger area of land, increasing total agricultural production. Low efficiency usually means that excess water

888-407: A diversion of the channel into the existing floodplain channel. The Brahmaputra channel is governed by the peak and low flow periods during which its bed undergoes tremendous modification. The Brahmaputra's bank line migration is inconsistent with time. The Brahmaputra river bed has widened significantly since 1916 and appears to be shifting more towards the south than towards the north. Together with

999-416: A flood (spate), water is diverted to normally dry river beds (wadis) using a network of dams, gates and channels and spread over large areas. The moisture stored in the soil will be used thereafter to grow crops. Spate irrigation areas are in particular located in semi-arid or arid, mountainous regions. Micro-irrigation , sometimes called localized irrigation , low volume irrigation , or trickle irrigation

1110-409: A higher profit than potatoes. The land is flood irrigated twice a day to simulate tidal flooding; the water is pumped from the sea using wind power. Additional benefits are soil remediation and carbon sequestration . Until the 1960s, there were fewer than half the number of people on the planet as of 2024. People were not as wealthy as today, consumed fewer calories and ate less meat , so less water

1221-424: A rectangular or square pattern. They are good for covering large, flat areas evenly. Impact (or Pulsating) Sprinklers: These create a rotating, pulsating spray, which can cover a circular or semi-circular area. They are useful for watering large lawns. Stationary Sprinklers: These have a fixed spray pattern and are best for smaller areas or gardens. Rotary Sprinklers: These use spinning arms to distribute water in

SECTION 10

#1732793565576

1332-708: A result of irrigation and the subsequent effects on natural and social conditions in river basins and downstream of an irrigation scheme . The effects stem from the altered hydrological conditions caused by the installation and operation of the irrigation scheme. Amongst some of these problems is depletion of underground aquifers through overdrafting . Soil can be over-irrigated due to poor distribution uniformity or management wastes water, chemicals, and may lead to water pollution . Over-irrigation can cause deep drainage from rising water tables that can lead to problems of irrigation salinity requiring watertable control by some form of subsurface land drainage . In 2000,

1443-424: A single sprinkler is combined with a valve and called a 'valve in head'. When used in a turf area, the sprinklers are installed with the top of the head flush with the ground surface. When the system is pressurized, the head will pop up out of the ground and water the desired area until the valve closes and shuts off that zone. Once there is no more pressure in the lateral line, the sprinkler head will retract back into

1554-711: A small discharge to each plant. Micro-irrigation uses less pressure and water flow than sprinkler irrigation. Drip irrigation delivers water directly to the root zone of plants. Subirrigation has been used in field crops in areas with high water tables for many years. It involves artificially raising the water table to moisten the soil below the root zone of plants. Irrigation water can come from groundwater (extracted from springs or by using wells ), from surface water (withdrawn from rivers , lakes or reservoirs ) or from non-conventional sources like treated wastewater , desalinated water , drainage water , or fog collection . Irrigation can be supplementary to rainfall , which

1665-609: A unique landscape along its course. Ledo , Margherita , Digboi , Duliajan and Naharkatia ( Nahorkotiya ) are the small towns in its valley. Dihing is one of the largest contributors to the Brahmaputra River. The plains of the Dihing Valley has a rich variety of flora and fauna. The Betel nuts are produced most in the areas of the Dihing Plains. According to historical as well as geographical records,

1776-399: Is supplementary to rainfall as happens in many parts of the world, or whether it is ' full irrigation' whereby crops rarely depend on any contribution from rainfall. Full irrigation is less common and only happens in arid landscapes experiencing very low rainfall or when crops are grown in semi-arid areas outside of any rainy seasons. Surface irrigation, also known as gravity irrigation, is

1887-631: Is a classic example of a braided river and is highly susceptible to channel migration and avulsion . It is also one of the few rivers in the world that exhibits a tidal bore . It is navigable for most of its length. The Brahmaputra drains the Himalayas east of the Indo-Nepal border, south-central portion of the Tibetan plateau above the Ganga basin, south-eastern portion of Tibet, the Patkai hills,

1998-480: Is a form of sprinkler irrigation utilising several segments of pipe (usually galvanized steel or aluminium) joined and supported by trusses , mounted on wheeled towers with sprinklers positioned along its length. The system moves in a circular pattern and is fed with water from the pivot point at the center of the arc. These systems are found and used in all parts of the world and allow irrigation of all types of terrain. Newer systems have drop sprinkler heads as shown in

2109-621: Is a natural phenomenon which is ecologically important because it helps maintain the lowland grasslands and associated wildlife. Periodic floods also deposit fresh alluvium, replenishing the fertile soil of the Brahmaputra River Valley. Thus flooding, agriculture, and agricultural practices are closely connected. The effects of flooding can be devastating and cause significant damage to crops and houses, serious bank erosive with consequent loss of homesteads, school and land, and loss of many lives, livestock, and fisheries. During

2220-503: Is a system where water is distributed under low pressure through a piped network, in a pre-determined pattern, and applied as a small discharge to each plant or adjacent to it. Traditional drip irrigation use individual emitters, subsurface drip irrigation (SDI), micro-spray or micro-sprinklers, and mini-bubbler irrigation all belong to this category of irrigation methods. Drip irrigation, also known as microirrigation or trickle irrigation, functions as its name suggests. In this system, water

2331-603: Is also called Tsangpo-Brahmaputra and red river of India (when referring to the whole river including the stretch within the Tibet Autonomous Region ). In its Tibetan and Indian names, the river is unusually masculine in gender. The upper reaches of the Brahmaputra River, known as the Yarlung Tsangpo from the Tibetan language, originates on the Angsi Glacier , near Mount Kailash, located on

SECTION 20

#1732793565576

2442-415: Is also the means of delivery of fertilizer. The process is known as fertigation . Deep percolation, where water moves below the root zone, can occur if a drip system is operated for too long or if the delivery rate is too high. Drip irrigation methods range from very high-tech and computerized to low-tech and labor-intensive. Lower water pressures are usually needed than for most other types of systems, with

2553-442: Is called Brahmaputra and Doima (mother of water) and Burlung-Buthur by native Bodo tribals, it then enters the state of Assam , and becomes very wide—as wide as 20 km (12 mi) in parts of Assam. The reason for such an unusual course and drastic change is that the river is antecedent to the Himalayas, meaning that it had existed before them and has entrenched itself since they started rising. The Dihang, winding out of

2664-422: Is common in many parts of the world as rainfed agriculture , or it can be full irrigation, where crops rarely rely on any contribution from rainfall. Full irrigation is less common and only occurs in arid landscapes with very low rainfall or when crops are grown in semi-arid areas outside of rainy seasons. The environmental effects of irrigation relate to the changes in quantity and quality of soil and water as

2775-535: Is crucial in planning upstream engineering to prevent flooding on the bridge. China had built the Zangmu Dam in the upper course of the Brahmaputra River in the Tibet region and it was operationalised on 13 October 2015. The main tributaries from the mouth: tributary tributary (km) (km ) (m /s) ( Sunkosh ) ( Bhareli ) ( Siyom ) (Matsang Tsangpo) Period: 1971–2000 The Kachari group called

2886-422: Is delivered at or near the root zone of plants, one drop at a time. This method can be the most water-efficient method of irrigation, if managed properly; evaporation and runoff are minimized. The field water efficiency of drip irrigation is typically in the range of 80 to 90% when managed correctly. In modern agriculture, drip irrigation is often combined with plastic mulch , further reducing evaporation, and

2997-457: Is dependent upon farmers having sufficient access to water. However, water scarcity is already a critical constraint to farming in many parts of the world. There are several methods of irrigation. They vary in how the water is supplied to the plants. The goal is to apply the water to the plants as uniformly as possible, so that each plant has the amount of water it needs, neither too much nor too little. Irrigation can also be understood whether it

3108-424: Is less expensive to install than a center pivot, but much more labor-intensive to operate – it does not travel automatically across the field: it applies water in a stationary strip, must be drained, and then rolled to a new strip. Most systems use 100 or 130 mm (4 or 5 inch) diameter aluminum pipe. The pipe doubles both as water transport and as an axle for rotating all the wheels. A drive system (often found near

3219-765: Is often called the Tsangpo-Brahmaputra river. The lower reaches are sacred to Hindus . While most rivers on the Indian subcontinent have female names, this river has a rare male name. Brahmaputra means "son of Brahma " in Sanskrit . It is known by various names in different regional languages: Brôhmôputrô in Assamese ; Tibetan : ཡར་ཀླུངས་གཙང་པོ་ , Wylie : yar klung gtsang po Yarlung Tsangpo ; simplified Chinese : 布拉马普特拉河 ; traditional Chinese : 布拉馬普特拉河 ; pinyin : Bùlāmǎpǔtèlā Hé . It

3330-421: Is often no alternative for farmers but to use water polluted with urban waste directly to water their crops. There can be significant health hazards related to using untreated wastewater in agriculture. Municipal wastewater can contain a mixture of chemical and biological pollutants. In low-income countries, there are often high levels of pathogens from excreta. In emerging nations , where industrial development

3441-443: Is often the irrigation choice for developing nations, for low value crops and for large fields. Where water levels from the irrigation source permit, the levels are controlled by dikes ( levees ), usually plugged by soil. This is often seen in terraced rice fields (rice paddies), where the method is used to flood or control the level of water in each distinct field. In some cases, the water is pumped, or lifted by human or animal power to

Dihing River - Misplaced Pages Continue

3552-422: Is outpacing environmental regulation, there are increasing risks from inorganic and organic chemicals. The World Health Organization developed guidelines for safe use of wastewater in 2006, advocating a ‘multiple-barrier' approach wastewater use, for example by encouraging farmers to adopt various risk-reducing behaviors. These include ceasing irrigation a few days before harvesting to allow pathogens to die off in

3663-586: Is practiced in the vineyards at Lanzarote using stones to condense water. Fog collectors are also made of canvas or foil sheets. Using condensate from air conditioning units as a water source is also becoming more popular in large urban areas. As of November 2019 a Glasgow-based startup has helped a farmer in Scotland to establish edible saltmarsh crops irrigated with sea water. An acre of previously marginal land has been put under cultivation to grow samphire , sea blite , and sea aster ; these plants yield

3774-520: Is significantly influenced by the melting of snow in the upper part of its catchment area. This increase in river flow, caused by the substantial retreat of snow, leads to a higher downstream discharge. Such a rise in discharge often results in severe catastrophic issues, including flooding and erosion. The Brahmaputra River is characterized by its significant rates of sediment discharge, the large and variable flows, along with its rapid channel aggradations and accelerated rates of basin denudation. Over time,

3885-478: Is similar in principle and action to subsurface basin irrigation. Another type of subirrigation is the self-watering container, also known as a sub-irrigated planter . This consists of a planter suspended over a reservoir with some type of wicking material such as a polyester rope. The water is drawn up the wick through capillary action. A similar technique is the wicking bed ; this too uses capillary action. Modern irrigation methods are efficient enough to supply

3996-437: Is supplied at one end using a large hose. After sufficient irrigation has been applied to one strip of the field, the hose is removed, the water drained from the system, and the assembly rolled either by hand or with a purpose-built mechanism, so that the sprinklers are moved to a different position across the field. The hose is reconnected. The process is repeated in a pattern until the whole field has been irrigated. This system

4107-419: Is supplied to plants. Surface irrigation , also known as gravity irrigation, is the oldest form of irrigation and has been in use for thousands of years. In sprinkler irrigation , water is piped to one or more central locations within the field and distributed by overhead high-pressure water devices. Micro-irrigation is a system that distributes water under low pressure through a piped network and applies it as

4218-795: Is the 9th largest river in the world by discharge, and the 15th longest . It originates in the Manasarovar Lake region, near Mount Kailash , on the northern side of the Himalayas in Burang County of Tibet where it is known as the Yarlung Tsangpo River . The Brahmaputra flows along southern Tibet to break through the Himalayas in great gorges (including the Yarlung Tsangpo Grand Canyon ) and into Arunachal Pradesh. It enters India near

4329-583: Is used for irrigation in agriculture, the nutrient (nitrogen and phosphorus) content of the treated wastewater has the benefit of acting as a fertilizer . This can make the reuse of excreta contained in sewage attractive. In developing countries , agriculture is increasingly using untreated municipal wastewater for irrigation – often in an unsafe manner. Cities provide lucrative markets for fresh produce, so they are attractive to farmers. However, because agriculture has to compete for increasingly scarce water resources with industry and municipal users, there

4440-556: Is usually not considered as a form of irrigation. Rainwater harvesting is the collection of runoff water from roofs or unused land and the concentration of this. Irrigation with recycled municipal wastewater can also serve to fertilize plants if it contains nutrients, such as nitrogen, phosphorus and potassium. There are benefits of using recycled water for irrigation, including the lower cost compared to some other sources and consistency of supply regardless of season, climatic conditions and associated water restrictions. When reclaimed water

4551-731: The Holocene . One idea about the most recent avulsion is that the change in the course of the main waters of the Brahmaputra took place suddenly in 1787, the year of the heavy flooding of the river Tista. In the middle of the 18th century, at least three fair-sized streams flowed between the Rajshahi and Dhaka Divisions, viz., the Daokoba, a branch of the Tista, the Monash or Konai, and

Dihing River - Misplaced Pages Continue

4662-519: The Jamalpur and Mymensingh districts. In an 8.8 magnitude earthquake on 2 April 1762 , however, the main channel of the Brahmaputra at Bhahadurabad point was switched southwards and opened as Jamuna due to the result of tectonic uplift of the Madhupur tract . Rising temperatures significantly contribute to snow melting in the upper Brahmaputra catchment. The discharge of the Brahmaputra River

4773-577: The United States , China , and European countries like the United Kingdom , also fund and organize some schemes within other nations. By 2021 the global land area equipped for irrigation reached 352 million ha, an increase of 22% from the 289 million ha of 2000 and more than twice the 1960s land area equipped for irrigation. The vast majority is located in Asia (70%), where irrigation

4884-573: The commercial greenhouse production, usually for potted plants . Water is delivered from below, absorbed by upwards, and the excess collected for recycling. Typically, a solution of water and nutrients floods a container or flows through a trough for a short period of time, 10–20 minutes, and is then pumped back into a holding tank for reuse. Sub-irrigation in greenhouses requires fairly sophisticated, expensive equipment and management. Advantages are water and nutrient conservation, and labor savings through reduced system maintenance and automation . It

4995-445: The 1998 flood, over 70% of the land area of Bangladesh was inundated, affecting 31 million people and 1 million homesteads. In the 1998 flood which had an unusually long duration from July to September, claimed 918 human lives and was responsible for damaging 1,600 km (990 mi) of roads and 6,000 km (3,700 mi) embankments, and affecting 6,000 km (2,300 sq mi) of standing crops. The 2004 floods, over 25% of

5106-639: The Bay of Bengal through the Meghna estuary and lesser channels flowing through the delta. The growth of the Ganga-Brahmaputra Delta is dominated by tidal processes. The Ganga Delta , fed by the waters of numerous rivers, including the Ganga and Brahmaputra, is 105,000 km (41,000 sq mi), one of the largest river deltas in the world. The Ganges – Brahmaputra – Meghna system has

5217-646: The Bay of Bengal. This final part of the river is called Meghna. The Brahmaputra enters the plains of Bangladesh after turning south around the Garo Hills below Dhuburi, India. After flowing past Chilmari, Bangladesh, it is joined on its right bank by the Tista River and then follows a 240 km (150 mi) course due south as the Jamuna River. (South of Gaibanda, the Old Brahmaputra leaves

5328-494: The Brahmaputra at Dihingmukh. Its watershed covers about 6,000 square kilometres (2,300 sq mi). The Dihing has created number of oxbow lakes in the area. Namdapha river is a tributary of the Dihing on its northern bank. Disang river is a tributary of the Dihing in its southern bank. The Jeypore-Dihing Rainforest, Namdapha National Park , numerous petroleum fields, wet-paddy fields, bamboo orchards and tea gardens provide

5439-460: The Brahmaputra at Pandu was 72,726 m /s (2,568,300 cu ft/s) August 1962 while the lowest was 1,757 m /s (62,000 cu ft/s) in February 1968. The increased rates of snow and glacial melt are likely to increase summer flows in some river systems for a few decades, followed by a reduction in flow as the glaciers disappear and snowfall diminishes. This is particularly true for

5550-537: The Brahmaputra is an important river for irrigation and transportation in the region. The average depth of the river is 30 m (100 ft) and its maximum depth is 135 m (440 ft) (at Sadiya ). The river is prone to catastrophic flooding in the spring when the Himalayan snow melts. The average discharge of the Brahmaputra is about ~22,000 m /s (780,000 cu ft/s), and floods reach about 103,000 m /s (3,600,000 cu ft/s). It

5661-560: The Daokoba, which was showing an equally rapid tendency to cut towards the east. The junction of these rivers gave the Brahmaputra a course worthy of her immense power, and the rivers to right and left silted up. In Renault's Altas they very much resemble the rivers of Jessore, which dried up after the hundred-mouthed Ganga had cut her new channel to join the Meghna at the south of the Munshiganj subdivision. Irrigation There are several methods of irrigation that differ in how water

SECTION 50

#1732793565576

5772-614: The Dihing once flowed through entire Upper Assam and met the Brahmaputra at Mahuramukh in Bokakhat . At that time the rivers Disang, Dikhou , Disai, Dhansiri were all tributaries to the Dihing. The river later dried out during the 17th century (as mentioned in Buranjis ) and changed course to join the Brahmaputra at Dihingmukh. Even before that, the river met the Brahmaputra near the confluence of Subansiri river . At that time

5883-797: The Dikhou river had an independent route and flowed as Kolong and joined the Brahmaputra at Kajalimukh in Nagaon district . Brahmaputra River The Brahmaputra is a trans-boundary river which flows through Southwestern China , Northeastern India , and Bangladesh . It is known as Brahmaputra or Luit in Assamese , Yarlung Tsangpo in Tibetan , the Siang/Dihang River in Arunachali , and Jamuna River in Bengali . By itself, it

5994-656: The Himalayas to the south and the Kailas Range to the north. In Tibet, the Tsangpo receives a number of tributaries. The most important left-bank tributaries are the Raka Zangbo (Raka Tsangpo), which joins the river west of Xigazê (Shigatse), and the Lhasa (Kyi), which flows past the Tibetan capital of Lhasa and joins the Tsangpo at Qüxü . The Nyang River joins the Tsangpo from the north at Zela (Tsela Dzong). On

6105-760: The Nile river in Egypt and Sudan; and in the Mississippi-Missouri river basin, the Southern Great Plains, and in parts of California in the United States. Smaller irrigation areas are spread across almost all populated parts of the world. By 2012, the area of irrigated land had increased to an estimated total of 3,242,917 km (801 million acres), which is nearly the size of India. The irrigation of 20% of farming land accounts for

6216-687: The Salangi. The Lahajang and the Elengjany were also important rivers. In Renault's time, the Brahmaputra as a first step towards securing a more direct course to the sea by leaving the Mahdupur Jungle to the east began to send a considerable volume of water down the Jinai or Jabuna from Jamalpur into the Monash and Salangi. These rivers gradually coalesced and kept shifting to the west till they met

6327-560: The adjacent floodplain. Lastly, flood basins are often formed between the levees of adjacent rivers. During the monsoon season (June–October), floods are a very common occurrence. Deforestation in the Brahmaputra watershed has resulted in increased siltation levels, flash floods, and soil erosion in critical downstream habitat, such as the Kaziranga National Park in middle Assam. Occasionally, massive flooding causes huge losses to crops, life, and property. Periodic flooding

6438-705: The ancient pilgrimage centre of Hajo , the Brahmaputra cuts through the rocks of the Shillong Plateau , and is at its narrowest at 1 km (1,100 yd) bank-to-bank. The terrain of this area made it logistically ideal for the Battle of Saraighat , the military confrontation between the Mughal Empire and the Ahom Kingdom in March 1671. The first combined railroad/roadway bridge across the Brahmaputra

6549-626: The capital of Bangladesh, and joins the Meghna River above Munshiganj. The Jamuna joins with the Ganga north of Goalundo Ghat, below which, as the Padma, their combined waters flow to the southeast for a distance of about 120 km (75 mi). After several smaller channels branch off to feed the Ganga-Brahmaputra delta to the south, the main body of the Padma reaches its confluence with the Meghna River near Chandpur and then enters

6660-469: The center pivot. This type of system is known as LEPA (Low Energy Precision Application). Originally, most center pivots were water-powered. These were replaced by hydraulic systems ( T-L Irrigation ) and electric-motor-driven systems (Reinke, Valley, Zimmatic). Many modern pivots feature GPS devices. A series of pipes, each with a wheel of about 1.5 m diameter permanently affixed to its midpoint, and sprinklers along its length, are coupled together. Water

6771-485: The centre of the wheel line) rotates the clamped-together pipe sections as a single axle, rolling the whole wheel line. Manual adjustment of individual wheel positions may be necessary if the system becomes misaligned. Wheel line systems are limited in the amount of water they can carry, and limited in the height of crops that can be irrigated. One useful feature of a lateral move system is that it consists of sections that can be easily disconnected, adapting to field shape as

SECTION 60

#1732793565576

6882-711: The components of these irrigation systems are hidden under ground, since aesthetics are important in a landscape. A typical lawn sprinkler system will consist of one or more zones, limited in size by the capacity of the water source. Each zone will cover a designated portion of the landscape. Sections of the landscape will usually be divided by microclimate , type of plant material, and type of irrigation equipment. A landscape irrigation system may also include zones containing drip irrigation, bubblers, or other types of equipment besides sprinklers. Although manual systems are still used, most lawn sprinkler systems may be operated automatically using an irrigation controller , sometimes called

6993-650: The construction of Brahmaputra Express Highways. The course of the Brahmaputra River has changed dramatically over the past 250 years, with evidence of large-scale avulsion, in the period 1776–1850, of 80 km (50 mi) from east of the Madhupur tract to the west of it. Prior to 1843, the Brahmaputra flowed within the channel now termed the "Old Brahmaputra" . The banks of the river are mostly weakly cohesive sand and silts, which usually erodes through large scale slab failure, where previously deposited materials undergo scour and bank erosion during flood periods. Presently,

7104-444: The contemporary slow migration of the river, the left bank is being eroded away faster than the right bank. The Brahmaputra River experiences high levels of bank erosion (usually via slab failure) and channel migration caused by its strong current, lack of riverbank vegetation, and loose sand and silt which compose its banks. It is thus difficult to build permanent structures on the river, and protective structures designed to limit

7215-408: The crop or field requirements. Increasing the application efficiency means that the amount of crop produced per unit of water increases. Improved efficiency may either be achieved by applying less water to an existing field or by using water more wisely thereby achieving higher yields in the same area of land. In some parts of the world, farmers are charged for irrigation water hence over-application has

7326-588: The deepening of the Bengal Basin caused by erosion will result in the increase in hydraulic radius, and hence allowing for the huge accumulation of sediments fed from the Himalayan erosion by efficient sediment transportation. The thickness of the sediment accumulated above the Precambrian basement has increased over the years from a few hundred meters to over 18 km (11 mi) in the Bengal fore-deep to

7437-471: The dry season when water availability is crucial for the irrigation systems. The course of the Brahmaputra River has changed drastically in the past two and a half centuries, moving its river course westwards for a distance of about 80 km (50 mi), leaving its old river course, appropriately named the old Brahmaputra river, behind. In the past, the floodplain of the old river course had soils which were more properly formed compared to graded sediments on

7548-410: The entire field uniformly with water, so that each plant has the amount of water it needs, neither too much nor too little. Water use efficiency in the field can be determined as follows: Increased irrigation efficiency has a number of positive outcomes for the farmer, the community and the wider environment. Low application efficiency infers that the amount of water applied to the field is in excess of

7659-502: The exception of low-energy center pivot systems and surface irrigation systems, and the system can be designed for uniformity throughout a field or for precise water delivery to individual plants in a landscape containing a mix of plant species. Although it is difficult to regulate pressure on steep slopes, pressure compensating emitters are available, so the field does not have to be level. High-tech solutions involve precisely calibrated emitters located along lines of tubing that extend from

7770-567: The flood problem remains unsolved. At least a third of the land of Majuli Island has been eroded by the river. Recently, it is suggested that a highway protected by concrete mat along the river bank and excavation of the river bed can curb this menace. This project, named the Brahmaputra River Restoration Project, is yet to be implemented by the government. Recently the Central Government approved

7881-534: The ground. In flower beds or shrub areas, sprinklers may be mounted on above ground risers or even taller pop-up sprinklers may be used and installed flush as in a lawn area. Hose-end sprinklers are devices attached to the end of a garden hose, used for watering lawns, gardens, or plants. They come in a variety of designs and styles, allowing you to adjust the water flow, pattern, and range for efficient irrigation. Some common types of hose-end sprinklers include: Oscillating Sprinklers: These spray water back and forth in

7992-409: The image that follows. As of 2017 most center pivot systems have drops hanging from a U-shaped pipe attached at the top of the pipe with sprinkler heads that are positioned a few feet (at most) above the crop, thus limiting evaporative losses. Drops can also be used with drag hoses or bubblers that deposit the water directly on the ground between crops. Crops are often planted in a circle to conform to

8103-490: The irrigation results in flooding or near flooding of the cultivated land. Historically, surface irrigation is the most common method of irrigating agricultural land across most parts of the world. The water application efficiency of surface irrigation is typically lower than other forms of irrigation, due in part to the lack of control of applied depths. Surface irrigation involves a significantly lower capital cost and energy requirement than pressurised irrigation systems. Hence it

8214-641: The left bank of the mainstream and flows past Jamalpur and Mymensingh to join the Meghna River at Bhairab Bazar.) Before its confluence with the Ganga, the Jamuna receives the combined waters of the Baral , Atrai , and Hurasagar Rivers on its right bank and becomes the point of departure of the large Dhaleswari River on its left bank. A tributary of the Dhaleswari, the Buriganga ("Old Ganga"), flows past Dhaka,

8325-399: The levee top and the surrounding floodplains is typically 1 m (3 ft) along small channels and 2–3 m (7–10 ft) along major channels. Crevasse splay, a sedimentary fluvial deposit which forms when a stream breaks its natural or artificial levees and deposits sediment on a floodplain, are often formed due to a breach in the levee, forming a lobe of sediments which progrades onto

8436-399: The level of the land. Surface irrigation is even used to water urban gardens in certain areas, for example, in and around Phoenix, Arizona . The irrigated area is surrounded by a berm and the water is delivered according to a schedule set by a local irrigation district . A special form of irrigation using surface water is spate irrigation , also called floodwater harvesting. In case of

8547-441: The line is moved. They are most often used for small, rectilinear, or oddly-shaped fields, hilly or mountainous regions, or in regions where labor is inexpensive. A lawn sprinkler system is permanently installed, as opposed to a hose-end sprinkler, which is portable. Sprinkler systems are installed in residential lawns, in commercial landscapes, for churches and schools, in public parks and cemeteries, and on golf courses . Most of

8658-519: The majority of the river's flow, continues due south as the Jamuna ( Jomuna ) to merge with the lower Ganga, called the Padma River ( Pôdma ). The eastern branch, formerly the larger, but now much smaller, is called the lower or Old Brahmaputra ( Brommoputro ). It curves southeast to join the Meghna River near Dhaka . The Padma and Meghna converge near Chandpur and flow out into

8769-510: The mountains, and one in late summer caused by runoff from monsoon rains. The river flow is strongly influenced by snow and ice melting of the glaciers, which are located mainly on the eastern Himalaya regions in the upstream parts of the basin. The snow and glacier melt contribution to the total annual runoff is about 27%, while the annual rainfall contributes to about 1.9 m (6 ft 3 in) and 22,000 m /s (780,000 cu ft/s) of discharge. The highest recorded daily discharge in

8880-528: The mountains, turns towards the southeast and descends into a low-lying basin as it enters northeastern Assam state. Just west of the town of Sadiya, the river again turns to the southwest and is joined by two mountain streams, the Lohit, and the Dibang. Below that confluence, about 1,450 km (900 mi) from the Bay of Bengal, the river becomes known conventionally as the Brahmaputra ("Son of Brahma"). In Assam,

8991-469: The northern side of the Himalayas in Burang County of Tibet . The source of the river was earlier thought to be on the Chemayungdung glacier, which covers the slopes of the Himalayas about 60 mi (97 km) southeast of Lake Manasarovar in southwestern Tibet. From its source, the river runs for nearly 1,100 km (680 mi) in a generally easterly direction between the main range of

9102-560: The northern slopes of the Meghalaya hills, the Assam plains, and northern Bangladesh. The basin, especially south of Tibet, is characterized by high levels of rainfall. Kangchenjunga (8,586 m) is the only peak above 8,000 m and hence is the highest point within the Brahmaputra basin. The Brahmaputra's upper course was long unknown, and its identity with the Yarlung Tsangpo was only established by exploration in 1884–86. The river

9213-435: The oldest form of irrigation and has been in use for thousands of years. In surface ( furrow, flood , or level basin ) irrigation systems, water moves across the surface of agricultural lands, in order to wet it and infiltrate into the soil. Water moves by following gravity or the slope of the land. Surface irrigation can be subdivided into furrow, border strip or basin irrigation . It is often called flood irrigation when

9324-512: The only bridge to span the river's major distributary, the Jamuna , was thus opened in June 1998. Constructed at a narrow braid belt of the river, it is 4.8 km (3.0 mi) long with a platform 18.5 m (61 ft) wide, and it is used to carry railroad traffic as well as gas, power and telecommunication lines. Due to the variable nature of the river, the prediction of the river's future course

9435-534: The operating Jamuna river. This change of river course resulted in modifications to the soil-forming process, which include acidification, the breakdown of clays and buildup of organic matter, with the soils showing an increasing amount of biotic homogenization, mottling, the coating around Peds and maturing soil arrangement, shape and pattern. In the future, the consequences of local ground subsidence coupled with flood prevention propositions, for instance, localised breakwaters, that increase flood-plain water depths outside

9546-436: The overarching goal of increasing self-sufficiency. Irrigation water can come from groundwater (extracted from springs or by using wells ), from surface water (withdrawn from rivers , lakes or reservoirs ) or from non-conventional sources like treated wastewater , desalinated water , drainage water , or fog collection . While floodwater harvesting belongs to the accepted irrigation methods, rainwater harvesting

9657-585: The part of Tibet to enter Indian state of Arunachal Pradesh , where the river is called Siang. It makes a very rapid descent from its original height in Tibet and finally appears in the plains, where it is called Dihang. It flows for about 35 km (22 mi) southward after which, it is joined by the Dibang River and the Lohit River at the head of the Assam Valley. Below the Lohit, the river

9768-679: The plateau to the south are the Burhi Dihing, the Disang, the Dikhu, and the Kopili. Between Dibrugarh and Lakhimpur Districts , the river divides into two channels—the northern Kherkutia channel and the southern Brahmaputra channel. The two channels join again about 100 km (62 mi) downstream, forming the Majuli island, which is the largest river island in the world. At Guwahati , near

9879-511: The population of Bangladesh or 36 million people, were affected by the floods; 800 people died; 952 000 houses were destroyed and 1.4 million were badly damaged; 24 000 educational institutions were affected including the destruction of 1200 primary schools, 2 million governments and private tube wells were affected, over 3 million latrines were damaged or washed away, this increases the risks of waterborne diseases including diarrhea and cholera. Also, 1.1 million ha (2.7 million acres) of

9990-567: The production of 40% of food production. The scale of irrigation increased dramatically over the 20th century. In 1800, 8 million hectares globally were irrigated, in 1950, 94 million hectares, and in 1990, 235 million hectares. By 1990, 30% of the global food production came from irrigated land. Irrigation techniques across the globe includes canals redirecting surface water, groundwater pumping, and diverting water from dams. National governments lead most irrigation schemes within their borders, but private investors and other nations, especially

10101-475: The regions saw increases in the area equipped for irrigation, with Africa growing the fastest (+29%), followed by Asia (+25%), Oceania (+24%), the Americas (+19%) and Europe (+2%). Irrigation enables the production of more crops, especially commodity crops in areas which otherwise could not support them. Countries frequently invested in irrigation to increase wheat , rice , or cotton production, often with

10212-498: The rice crop was submerged and lost before it could be harvested, with 7% of the yearly aus (early season) rice crop lost; 270,000 ha (670,000 acres) of grazing land was affected, 5600 livestock perished together with 254 00 poultry and 63 million tonnes (69 million short tons) of lost fish production. Flood-control measures are taken by the water resource department and the Brahmaputra Board, but until now

10323-464: The right bank, a second river called the Nyang Qu (Nyang Chu) meets the Tsangpo at Xigazê. After passing Pi (Pe) in Tibet, the river turns suddenly to the north and northeast and cuts a course through a succession of great narrow gorges between the mountainous massifs of Gyala Peri and Namcha Barwa in a series of rapids and cascades. Thereafter, the river turns south and southwest and flows through

10434-399: The river "Dilao", "Tilao". Early Greek accounts of Curtius and Strabo give its name as Dyardanes ( Ancient greek Δυαρδάνης) and Oidanes. In the past, the course of the lower Brahmaputra was different and passed through the Jamalpur and Mymensingh districts. Some water still flows through that course, now called the Old Brahmaputra, as a distributary of the main channel. A question about

10545-468: The river is mighty, even in the dry season, and during the rains, its banks are more than 8 km (5.0 mi) apart. As the river follows its braided 700 km (430 mi) course through the valley, it receives several rapidly flowing Himalayan streams, including the Subansiri, Kameng, Bhareli, Dhansiri, Manas, Champamati, Saralbhanga, and Sankosh Rivers. The main tributaries from the hills and from

10656-487: The river system in Bangladesh is when and why the Brahmaputra changed its main course, at the site of the Jamuna and the "Old Brahmaputra" fork that can be seen by comparing modern maps to historic maps before the 1800s. The Brahmaputra likely flowed directly south along its present main channel for much of the time since the last glacial maximum , switching back and forth between the two courses several times throughout

10767-449: The river's erosion rate has decreased to 30 m (98 ft) per year as compared to 150 m (490 ft) per year from 1973 to 1992. This erosion has, however, destroyed so much land that it has caused 0.7 million people to become homeless due to loss of land. Several studies have discussed the reasons for the avulsion of the river into its present course, and have suggested a number of reasons including tectonic activity, switches in

10878-491: The river's erosional effects often face numerous issues during and after construction. In fact, a 2004 report by the Bangladesh Disaster and Emergency Sub-Group (BDER) has stated that several of such protective systems have 'just failed'. However, some progress has been made in the form of construction works which stabilize sections of the river, albeit with the need for heavy maintenance. The Bangabandhu Bridge ,

10989-406: The second-greatest average discharge of the world's rivers—roughly ~44,000 m /s (1,600,000 cu ft/s), and the river Brahmaputra alone supplies about 50% of the total discharge. The rivers' combined suspended sediment load of about 1.87 billion tonnes (1.84 billion tons) per year is the world's highest. In the past, the lower course of the Brahmaputra was different and passed through

11100-504: The south. The ongoing subsidence of the Bengal Basin and the high rate of Himalayan uplift continues to contribute to the large water and sediment discharges of fine sand and silt, with 1% clay, in the Brahmaputra River. Climatic change plays a crucial role in affecting the basin hydrology. Throughout the year, there is a significant rise in hydrograph, with a broad peak between July and September. The Brahmaputra River experiences two high-water seasons, one in early summer caused by snowmelt in

11211-400: The sprinkler arrives back at the reel the system shuts off. This type of system is known to most people as a "waterreel" traveling irrigation sprinkler and they are used extensively for dust suppression, irrigation, and land application of waste water. Other travelers use a flat rubber hose that is dragged along behind while the sprinkler platform is pulled by a cable. Center pivot irrigation

11322-493: The sunlight; applying water carefully so it does not contaminate leaves likely to be eaten raw; cleaning vegetables with disinfectant; or allowing fecal sludge used in farming to dry before being used as a human manure. Irrigation water can also come from non-conventional sources like treated wastewater , desalinated water , drainage water , or fog collection . In countries where humid air sweeps through at night, water can be obtained by condensation onto cold surfaces. This

11433-812: The total fertile land was 2,788,000 km (689 million acres) and it was equipped with irrigation infrastructure worldwide. About 68% of this area is in Asia, 17% in the Americas, 9% in Europe, 5% in Africa and 1% in Oceania. The largest contiguous areas of high irrigation density are found in Northern and Eastern India and Pakistan along the Ganges and Indus rivers; in the Hai He, Huang He and Yangtze basins in China; along

11544-463: The upstream course of the Teesta River, the influence of increased discharge, catastrophic floods and river capture into an old river course. From an analysis of maps of the river between 1776 and 1843, it was concluded in a study that the river avulsion was more likely gradual than catastrophic and sudden, and may have been generated by bank erosion, perhaps around a large mid-channel bar, causing

11655-802: The village of Gelling in Arunachal Pradesh and flows southwest through the Assam Valley as the Brahmaputra and south through Bangladesh as the Jamuna (not to be confused with the Yamuna of India). In the vast Ganges Delta , it merges with the Ganges , popularly known as the Padma in Bangladesh, and becomes the Meghna and ultimately empties into the Bay of Bengal . At 3,000 km (1,900 mi) long,

11766-441: The water breakers, may alter the water levels of the floodplains. Throughout the years, bars, scroll bars, and sand dunes are formed at the edge of the flood plain by deposition. The height difference of the channel topography is often not more than 1–2 m (3–7 ft). Furthermore, flooding over the history of the river has caused the formation of river levees due to deposition from the overbank flow. The height difference between

11877-405: The water source by a hose. Automatically moving wheeled systems known as traveling sprinklers may irrigate areas such as small farms, sports fields, parks, pastures, and cemeteries unattended. Most of these use a length of polyethylene tubing wound on a steel drum. As the tubing is wound on the drum powered by the irrigation water or a small gas engine, the sprinkler is pulled across the field. When

11988-414: The water table to allow the soil to be moistened from below the plants' root zone. Often those systems are located on permanent grasslands in lowlands or river valleys and combined with drainage infrastructure. A system of pumping stations, canals, weirs and gates allows it to increase or decrease the water level in a network of ditches and thereby control the water table. Subirrigation is also used in

12099-413: Was a key component of the green revolution; the Americas account for 16% and Europe for 8% of the world total. India (76 million ha) and China (75 million ha) have the largest equipped area for irrigation, far ahead of the United States o fAmerica (27 million ha). China and India also have the largest net gains in equipped area between 2000 and 2020 (+21 million ha for China and +15 million ha for India). All

12210-613: Was constructed at Saraighat . It was opened to traffic in April 1962. The environment of the Brahmaputra floodplains in Assam have been described as the Brahmaputra Valley semi-evergreen forests ecoregion . In Bangladesh, the Brahmaputra is joined by the Teesta River (or Tista), one of its largest tributaries. Below the Tista, the Brahmaputra splits into two distributary branches. The western branch, which contains

12321-666: Was needed to produce their food. They required a third of the volume of water humans presently take from rivers. Today, the competition for water resources is much more intense, because there are now more than seven billion people on the planet, increasing the likelihood of overconsumption of food produced by water-thirsty animal agriculture and intensive farming practices. This creates increasing competition for water from industry , urbanisation and biofuel crops . Farmers will have to strive to increase productivity to meet growing demands for food , while industry and cities find ways to use water more efficiently. Successful agriculture

#575424