Khadar

Geography glossary

Also called: New alluvium · Topic: Structure and Physiography of India: Himalayas, Plains, Peninsula, Coasts and Islands · NCERT: Class 10, Ch 1 "Resources and Development"; Class 11, Ch 2 "Structure and Physiography"

Meaning

Khadar is the newer alluvium (fresh silt and clay left by rivers) on the low floodplains of rivers in the Northern Plain, and floods spread a new layer of silt over it almost every year. Because its soil keeps getting renewed, it is the most fertile farmland in the plain. The same flooding also makes khadar areas prone to floods and waterlogging.

Explanation

How khadar forms

  • Cause: rivers carry silt and overflow their banks
  • Himalayan rivers like the Ganga, Yamuna and Brahmaputra carry a heavy load of sediment.

  • In the monsoon, they spill over their banks onto the floodplain (the low, flat land next to a river that gets flooded).

  • Process: fresh silt is dropped

  • When floodwater spreads out, it slows down.

  • Slow water cannot carry its load, so it drops fine silt and clay on the land.

  • Result: a new layer of soil almost every year

  • Each flood adds fresh silt on top of the old layer.
  • This is why khadar is called new alluvium. Its soil is young and constantly renewed.

Main features

  • Position: low floodplains close to the river, below the raised bhangar terraces.
  • Texture: fine-grained (silt and clay), not coarse like the bhabar.
  • Kankar: absent. Kankar (lumps of lime, or calcium carbonate, in the soil) is a mark of the older bhangar.
  • Fertility: very high, because floods keep bringing fresh nutrients.
  • Farming: best for intensive farming (growing crops on the same land again and again, with high output). Crops include rice, wheat, sugarcane and jute.

Place in the north–south zones

  • Order to remember: Shiwalik foothills → Bhabar → Tarai → Bhangar/Khadar → delta.
  • Bhabar: coarse pebbles; streams sink and disappear.
  • Tarai: streams come back up; marshes and swamps.
  • Bhangar: older alluvium on terraces above flood level.

  • Khadar: newer alluvium on floodplains, flooded almost every year.

  • Bhangar and khadar sit side by side across the plain. Bhangar is the higher "step" (a terrace: a flat step of land left high when the river cut deeper). Khadar is the low land the river still floods.

Conditions it needs

  • A river with a heavy sediment load, such as the Himalayan rivers.
  • Regular seasonal floods, mostly in the monsoon.
  • A gentle slope. In this mature stage the river flows sideways and drops sediment instead of cutting downward. This also produces meanders, oxbow lakes, sand bars and braided channels on the khadar.

Where it occurs

  • Indo-Ganga-Brahmaputra plain: it is about 3,200 km long and 150-300 km wide, at only 50-150 m above sea level. The alluvium here is up to 1,000-2,000 m thick. Khadar strips run along the river channels throughout it.
  • Punjab-Haryana plain: floodplains of the Satluj, Beas and Ravi (Indus tributaries), within the doabs.
  • Ganga plain (Delhi to West Bengal): floodplains of the Ganga, Yamuna, Ghaghara, Gandak, Kosi and Son.

  • The Kosi (Bihar) is called the "Sorrow of Bihar". It floods often and shifts its course over its floodplain.

  • Brahmaputra plain (Assam): a narrow valley with braided channels, riverine islands and yearly floods.

  • Majuli (Assam), in the Brahmaputra, is part of the river's alluvial floodplain. Its soil is mostly silt with no cohesion (the soil does not stick together), so it erodes easily [2].
  • The island shrank from 734 sq km in 1914 to 502 sq km in 2004 [2].

Don't confuse with

  • Bhangar: older alluvium on raised terraces above flood level. It is not renewed by floods, contains kankar and is less fertile. Khadar is the newer, kankar-free and more fertile floodplain alluvium.
  • Bhabar: an 8-10 km belt of boulders, pebbles and gravel at the foot of the Shiwaliks, where streams disappear. Khadar is fine silt far down in the plain.
  • Tarai: a 10-20 km wet, marshy belt where underground streams come back to the surface. It is defined by swamps and forest, not by yearly flood silt.
  • Delta: a fan-shaped landform at the river mouth, built by distributaries, for example the Sundarbans. Khadar is the floodplain soil along the river's course, not at its mouth.

Prelims Hooks

  • Khadar = new alluvium, on floodplains, renewed almost every year. Bhangar = old alluvium, on terraces above flood level.
  • Kankar (lime nodules) belongs to bhangar, not khadar. This is a common "which of the following" trap.
  • North to south order: Shiwalik → Bhabar → Tarai → Bhangar → Khadar.
  • Fertility ranking: khadar is more fertile than bhangar. Bhabar is the poorest for farming because it is coarse and dry on the surface.
  • Process–landform pair: yearly overbank flooding with silt deposition → khadar. Rivers dropping coarse load at the break of slope (where steep hills suddenly meet flat ground) → bhabar.
  • Majuli (Brahmaputra, Assam) is floodplain silt with no cohesion. It became India's first island district in 2016 [2].

Mains Points

  • Fertility vs. flood risk (GS-I):
  • The same floods that make khadar fertile also bring yearly danger.
  • Khadar areas suffer floods, waterlogging and river avulsion (a river suddenly shifting to a new course), as seen with the Kosi, the "Sorrow of Bihar".

  • Dense settlement on fertile khadar raises the human and economic losses each monsoon.

  • Food bowl and population (GS-I):

  • Fine, renewed khadar soil, flat land and perennial Himalayan rivers support intensive farming of wheat, rice, sugarcane and jute.

  • This makes the khadar belts the core of the Indo-Gangetic plain's role as India's agricultural and demographic heartland.

  • Erosion of floodplain land (GS-III, disasters):

  • Loose khadar silt is easily cut away by braided, sediment-heavy rivers. Majuli lost 206.7 sq km between 1949 and 2004, and erosion worsened after the 1950 Assam earthquake [2].
  • The Brahmaputra Board started embankments and RCC porcupine screens (concrete frames that slow water and trap silt) in January 2004 [2]. These need to be combined with basin-level river management.

Related concepts

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Sources

  1. 1Class 10, Ch 1 "Resources and Development"; Class 11, Ch 2 "Structure and Physiography" (primary)
  2. 2PIB — Protection of Majuli Islandpib.gov.in · tier 1