Question

Give a brief account of the characteristics of alluvial soil.

Hint:

Alluvial soil = \textbf{Fertile + Potash-rich + Indo-Gangetic plains}.

Answer 1

Step 1: Formation.
Alluvial soil is formed by the deposition of silt, sand, and clay carried by rivers (Indus, Ganga, Brahmaputra). It covers the Indo-Gangetic plains and river valleys.
Step 2: Physical features.
- Texture: Ranges from sandy loam to clayey.
- Colour: Generally light grey to ash-grey.
- Strata: Newer alluvium (Khadar) and older alluvium (Bhangar).
Step 3: Chemical composition.
- Rich in potash, lime, and phosphoric acid.
- Deficient in nitrogen and humus.
Step 4: Agricultural importance.
- Most fertile soil in India; supports cultivation of rice, wheat, sugarcane, cotton, jute, and pulses.
- Alluvial plains are called the granaries of India.
Step 5: Conclusion.
Thus, alluvial soil is the most widespread and agriculturally important soil, sustaining a large part of India’s population.