TheIndus Basinis the part ofAsiadrained by theIndus Riverand its tributaries. The basin covers an area of 1,120,000 km2(430,000 sq mi)[1][a]traversing four countries:Afghanistan,China,India,andPakistan,with most of the area lying predominantly in the latter two countries.

The Indus Basin

Geography

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The Indus River has two main tributaries: thePanjnad—formed by successive confluences ofSutlej,Beas,Ravi,Jhelum,andChenab Rivers—and theKabul,containing the waters of theSwatandKunar Rivers,as well as others. The Indus and Sutlej originate on theTibetan Plateau,the Ravi, Beas, Chenab and Jhelum originate in the Indian westernHimalayas,and the Kabul and its tributaries originate in theHindu Kushof eastern Afghanistan and northern Pakistan.

The Indus Basin lies in four countries: Pakistan, India, China, and Afghanistan. The largest portion of the basin, at 47%, lies in Pakistan while India contains the second biggest share at 39%. China and Afghanistan contain the remaining 14%.[3][4]The Indus Basin spans the length of Pakistan, constitutes a majority (65%) of its area and forms part of all provinces and territories of the country:Punjab,Sindh,Khyber Pakhtunkhwa,Balochistan,Azad Kashmir,andGilgit-Baltistan,with all except Sindh and Balochistan located entirely within the basin. In India, the Indus Basin forms less than 14% of the territory but makes up the bulk of the northwestern part of the country including the states and union territories ofPunjab,Himachal Pradesh,Jammu and Kashmir,Ladakh,Haryana,andRajasthan,constituting the whole or major portion of all of them except for the last.

The Indus River inKhyber Pakhtunkhwa
Spiti,a tributary of the Satluj, inHimachal Pradesh

The Indus Basin consists of various topographical regions. A large part of thedrainage basinis mountainous, and around 40% of its area lies above an elevation of 2,000 m (6,600 ft).[4]The basin can be divided into two wide physiographic divisions: the upper basin consisting of the mountainous regions of the Himalaya,Karakoram,Hindu Kush,Shiwalik,Suleiman,andKirtharranges; and the lower basin consisting of theIndus Plainsincluding the alluvial plains of thePunjaband Sindh.[3]Most of the basin is arid or semi-arid, with the exception of the Himalayan foothills which receive significant rainfall.

The basin contains the largest amount of perennialglacial iceoutside of the polar regions.[1]A majority of the runoff in the Indus drainage basin comes frommeltwater—glacial melt contributing 41% andsnowmeltproviding 22%—of the Himalaya, Hindu Kush and Karakorum mountains.[5]Rainfall contributes the remaining. On average, a little over half of the entire annual flow is received within the three months from July to September, whenmonsoonal rainscombine with meltwater.[6]As a result, the region has historically seen substantial flooding in the summer months.[7]

Water use

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The Indus drainage supports some 237 million people. Pakistan contains a majority of the people living in the Indus Basin (around 61% of total) most of whom heavily depend on its rivers for their water needs. India contains another large portion (35%) of the Indus Basin's population. The remaining 4% live mostly in Afghanistan, representing a little less than a quarter of the country's population.[2]The Indus Basin is the second mostwater stressedbasin of the world.[8]

93% of the water of the Indus Basin is used for irrigation of agricultural land.[9]Many of the rivers of the Indus River system are dammed to create large reservoirs of water: in India the Satluj river is dammed atBhakracreating theGobind Sagarreservoir, the Beas atPongcreating theMaharana Pratap Sagarreservoir and the Ravi atTheincreating the Ranjit Sagar reservoir; while in Pakistan the Jhelum river is dammed atManglaand the Indus is dammed atTarbelaandChashmacreating the Mangla,Tarbelaand Chashma reservoirs respectively. The water from these reservoirs as well as from various barrages are diverted to irrigate 26 million hectares (mha) of agricultural land, 16 mha in Pakistan and 10 mha in India.[10]

See also

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References

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  1. ^Other estimates put the area of the basin between 1,080,000 km2(420,000 sq mi) and 1,137,817 km2(439,314 sq mi)[2]
  1. ^abShrestha et al. 2015,p. 58
  2. ^abLaghari, Vanham & Rauch 2012,p. 1064
  3. ^abShrestha, Wagle & Rajbhandari 2019,p. 145
  4. ^abCheema & Qamar 2019,p. 183.
  5. ^Shrestha et al. 2015,p. 21
  6. ^Gilmartin 2015,p. 14.
  7. ^Gilmartin 2015,p. 15.
  8. ^Richey, Alexandra S.; Thomas, Brian F.; Lo, Min-Hui; Reager, John T.; Famiglietti, James S.; Voss, Katalyn; Swenson, Sean; Rodell, Matthew (2015-07-16)."Quantifying renewable groundwater stress with GRACE".Water Resources Research.51(7): 5217–38.Bibcode:2015WRR....51.5217R.doi:10.1002/2015WR017349.PMC4744761.PMID26900185.
  9. ^Cheema & Qamar 2019,p. 189.
  10. ^Cheema & Qamar 2019,p. 184.

Bibliography

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