NCERT 9 GEOGRAPHY CHAPTER 3
3. Drainage
- Drainage - river system of an area (small streams to form main river which drains into lake/sea/ocean)
- Drainage basin - Area drained by a single river
- Amazon river - World's largest drainage basin
A)The Himalayan Rivers
- Perennial (water throughout the year from rain as well as from melted snow)
- Upper course - intensive erosional activities carry huge loads of silt and sand
- Lower course - form meanders (bend in river channel), ox-bow lakes (cut-off lake)
- Seasonal (dependent on rainfall)
- have shorter and shallower course
1.THE INDUS RIVER SYSTEM
- rises in the Tibet, enters India in Ladakh
- several tributaries -the Zaskar, the Nubra, the Shyok, the Hunza (join it in Kashmir)
- Flows through Baltistan and emerges from mountains at Attock
- The Satluj, the Beas, the Ravi, the Chenab, the Jhelum - join together near Mithankot (Pakistan)
- drains into Arabian Sea(east of Karachi)
- The Indus plain with a length of 2900km
- One of the longest rivers of the world
- Indus basin - Jammu and Kashmir, Himachal Pradesh, Punjab and the rest in Pakistan
- Indus Water Treaty(1960) - India can use only 20 % of total water from the Indus river system
- Confluence of Bhagirathi (fed by Gangotri Glacier) and Alaknanda at Devaprayag in Uttarkhand
- Right bank tributaries - the Yamuna (from the Yamunotri Glacier), the Ghanghara, the Gandak and the Kosi (from Nepal Himalayas, causes flooding and widespread damage every year)
- Left bank tributaries - the Chambal, the Betwa, the Son (from peninsular uplands, have shorter course, not carry much water)
- flows till Farakka in West Bengal, bifurcates as Bhagirathi - Hooghly river (drains into Bay of Bengal) and into Bangladesh (joined by Brahmaputra)
- Downstream known as Meghna, flows into Bay of Bengal, form a Delta known as Sundarban Delta (word derived from Sundari tree, World's largest and fast growing delta, also the home of Royal Bengal Tiger)
- The length of river Ganga is 2500 km
- The Namami Ganga Programme - "Integrated Conservation Mission" in 2014, Twin objective - abatement of Pollution, Conservation and Rejuvenation of River Ganga
- rises in Tibet, very close to the Indus and the Satluj
- slightly longer than the Indus
- most of its course lies outside India and 'U' turn from Namacha Barwa (7757 m) enters Arunachal Pradesh(the Dihang joined with the Dibang, the Lohit to Brahmaputra in Assam)
- Brahmaputra called as Tsang po in Tibet and Jamuna in Bangladesh)
- has braided channel and forms many riverine island
- The Mahanadi, the Godavari, the Krishna and the Kaveri - flow eastwards drains into Bay of Bengal and forms Delta
- (Delta- triangular landform formed due to deposits from the rivers, fertile area)
- The Narmadi and the Tapi - only long west flowing rivers and forms estuaries
- (Estuaries - semi enclosed body of water, region of mixing of fresh river water and salt sea water, devoid of deposits)
- rises in the Amarkantak hills in Madhya Pradesh
- flows west in a rift valley (formed due to faulting)
- creates picturesque locations (The Marble rocks, the Dhuadhar falls)
- covers parts of Madhya Pradesh and Gujarat
- The Namami Devi Narmade - The Narmada river conservation mission
- rises in the Satpura ranges, in Betul in Madhya Pradesh
- flows parallel to the Narmada but shorter in length
- basin covers parts of Madhya Pradesh, Gujarat, Maharashtra
3.THE GODAVARI BASIN
- The largest Peninsular river
- rises in Nasik in Maharashtra
- length - 1500 km
- largest drainage basin among peninsular rivers, drains into Bay of Bengal
- Tributaries - the Purna, the Wardha, the Pranhita, the Manjra, the Wainganga, the Penganga
- basin covers parts of Maharashtra, Odisha, Andhra Pradesh
- Also known as Dakshin Ganga (Ganges of the South)
- rises in the highlands of Chhattisgarh
- length - 860 km
- basin covers Maharashtra, Chhattisgarh, Jharkhand and Odisha
- rising from a spring near Mahabaleshwar, Maharashtra
- length - 1400 km
- tributaries - the Tungabhadra, the Koyana, the Ghatprabha, the Musi and the Bhima
- basin covers Maharashtra, Karnataka, Andhra Pradesh
- rises in the Brahmagiri range of the Western Ghats
- length - 760 km
- tributaries - Amaravati, Bhavani, Hemavati, Kabini
- drains parts of Karnataka, Kerala and Tamil Nadu
- makes the second biggest waterfall in India - Shivasamudram Falls
LAKES
- India has many lakes
- Lakes of large extent are called Sea - the Caspian, the Dead and the Aral seas
- ox-bow lakes - a meandering river across a flood plain forms cut off lakes
- spits and bars form lagoons (water body separated from large water body by natural barrier)
- Eg : the Chilika lake, the Pulicat lake, the Kolleru lake
- seasonal - the Sambhar lake in Rajasthan (salt water lake, producing salt)
- freshwater lakes - permanent, glacial origin
- The Wular lake - the largest freshwater lake in India, is formed by tectonic activity
- other freshwater lakes - the Dal lake, the Bhimtal lake, Nainital, Loktak and Barapani
- Damming of rivers also led to form lakes
- Eg : Guru Gobind Sagar (Bakra Nangal Project) for generation of Hydel Power
ROLE OF RIVERS - basic natural resource, attracted settlers from ancient times, essential for irrigation, navigation, hydro-electric power generation
NATIONAL RIVER CONSERVATION PLAN (NRCP)
- To improve the water quality
- The river cleaning programme (Ganga Action Plan in 1985) expanded to cover other rivers under NRCP in 1995
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