Question

Distinguish between :
(a) Khadar and Bhangar
(b) A Delta and an Estuary

Answer 1

(a) Khadar : The level of flood plain which has younger alluvium deposited by the river is called khadar. This zone is fertile and supports intensive cultivation.

Bhangar : lt is a zone of old alluvium with coarse structure having pebbles etc. This zone is less fertile.

(b) Delta : ln the lower course as the speed of the river becomes very sluggish, it deposits fine silts and mud in the channel and the river is forced to split to overcome obstructions. These channels, which carry away a part of river water are called distributaries and a vast triangular shape plain appears on the land known as delta.

Estuary : When the river flows on a slightly inclined land before entering the sea, it has swift flow. lt drains directly into the sea in a deep narrow channel known as an estuary. It does not make a delta. The Narmada and Tapi make estuaries in the Arabian sea.

Answer 2

(a)Khadar and Bhangar::---
1. Old alluvium:Bhangar, New alluvium:Khadar.
2.Bhangar:Less fertile,Khadar:More fertile.
3.Bhangar:Continuous deposition of alluvium,Khadar:Renewal of soil every year.
4.Bhangar:That part where flood water cannot reach,Khadar:flood water spreads every year and thin layer of soil spreads.


(b)A Delta and an Estuary::---
A river delta is a triangular river mouth with several branches, side flows and bayous. The delta is formed by the silt and terrain carried by the river flow along the river, and it little by little lenghtens the flow of the river towards the sea.

An estuary is a river mouth which resembles a funnel and which widens, deepens and opens toward the sea. An estuary is formed by a tidal bore, which ablates the riverbed and carries the silt out to sea.