Northern Plains

Notes

The Northern Plains were formed by the deposition of alluvium by the Indus, Ganga and Brahmaputra rivers in a trough between the Himalaya and the Peninsular Plateau. They are about 2,400 km long and 240-320 km wide, and support about 40% of India's population.

Divisions by relief

Bhabar: a narrow (8-16 km) pebbly belt at the foot of the Shiwaliks, where streams disappear underground.
Terai: a marshy, damp belt south of the Bhabar where streams re-emerge; originally thick forest and rich wildlife, much now cleared for agriculture.
Bhangar: old alluvium, forming terraces above flood level, often containing kankar (calcareous nodules).
Khadar: new alluvium, found in the flood plains, renewed every year, and more fertile.

Regional divisions

Punjab Plains: formed by the Indus and its tributaries (Jhelum, Chenab, Ravi, Beas, Sutlej); interfluves are called doabs (the Bist-Jalandhar, Bari, Rechna, Chaj and Sind Sagar doabs).
Ganga Plain: from the Ghaggar to the Teesta; the upper (Ganga-Yamuna doab), middle (Bihar, with the Kosi) and lower (West Bengal, the Sundarbans delta, the world's largest delta).
Brahmaputra Plain (Assam valley): includes Majuli, the world's largest river island.
Rajasthan Plain in the west merges with the desert.

Significance: fertile soil and a large irrigated area (wheat, rice, sugarcane), dense population, industries, transport, historic civilisations.

Key Points

Alluvial plains of the Indus, Ganga and Brahmaputra.
Bhabar (pebbles, streams vanish), Terai (marsh), Bhangar (old), Khadar (new).
Doabs in Punjab; Sundarbans delta is the world's largest.
Majuli is the largest river island in the world.
About 40% of India's population lives here.

MCQs

Q1. In the Bhabar belt:
(a) Streams re-emerge
(b) Streams disappear underground
(c) Black soil is found
(d) Laterite occurs
Ans: (b).

Q2. The new alluvium of the flood plains is called:
(a) Bhangar
(b) Khadar
(c) Terai
(d) Bhabar Ans:
(b).

Q3. Majuli, the largest river island in the world, is on the:
(a) Ganga
(b) Brahmaputra
(c) Godavari
(d) Indus Ans:
(b).