Alluvial Soil

Alluvium means deposit of clay, silt, and sand left by flowing floodwater in a river valley or delta, typically producing fertile soil.

Alluvial soil is the most important soil type of India. It covers the vast valley areas of the Sutlej, Ganga and Brahmaputra and the fringes of the southern peninsula. It is thin near the fringe of the plateau.

The alluvial soils vary from sandy loam to clay in texture and are rich in potash but deficient in nitrogen and organic matter. Generally, the colour varies from grey to reddish brown.

These soil are formed of deposits of silt and sand brought down by the rivers flowing from the Himalayas and the Great Indian plateau.

Being young, the soils lack profile development. Being extremely productive, these soils are most important for agriculture. Based on geographical considerations, this soil can be subdivided into two divisions:

  1. Newer alluvium (khadar)
  2. Older alluvium (bangar)

Both are different in texture, chemical composition, drainage capacity and fertility. The newer alluvium is a light friable loam with a mixture of sand and silt. It is found in river valley, the floodplains and deltas. On the other hand, the older alluvium lies on the inter fluves. The higher proportion of clay makes the soil sticky and drainage is often poor.