Piedmont alluvial plains
Topic: Structure and Physiography of India: Himalayas, Plains, Peninsula, Coasts and Islands · NCERT: Class 10, Ch 1 "Resources and Development"
Meaning
Piedmont alluvial plains are plains at the foot of mountains ("piedmont" means foot of the mountain). They form at the break of slope, where a steep mountain slope suddenly flattens. Rivers lose speed there and drop coarse sediment such as gravel and sand. In India these plains lie along the foot of the Himalayas and the Shiwalik.
Example
The Duars are piedmont plains in the foothills of north Bengal and Assam, known for tea gardens. Others are the chos of the Punjab Shiwaliks, where seasonal torrents cut up bare slopes, and the tarai, a marshy, forested belt south of the bhabar where streams that sank into the ground come back to the surface.
Don't confuse with
- Khadar: this is new, fine and very fertile alluvium on river floodplains, far out in the plain and renewed by floods almost every year. Piedmont plains lie at the mountain foot and are made of coarser material.
Related concepts
- Indo-Ganga-Brahmaputra plain
- Bhabar
- Tarai
- Bhangar
- Khadar
- Riverine island
- Majuli
- Ganga-Brahmaputra delta