The sluggish water of the river is turned at the slightest obstruction. This can form a system of meanders, oxbow lakes, or even braided rivers. Let us learn what is a meander, an ox-bow lake, and a braided river.

 

Meanders

 

The word Meander is derived from the name of a small river Meanders in Turkey. This river has numerous loops or meanders in its course. Meander is formed due to both deposition and erosion.

 

In the middle course, the river has more energy and a high volume of water with a gentle gradient. The alternating bars of sediments force the water to weave around them. The swing of river water results in erosion by cutting on one side and depostion on the other, leading to the formation of the meander.

 

The shape of the loop or meander is usually semi-circular but sometimes it is also circular.

 

The meandering of the river is a natural process and is controlled by a number of factors, such as:

 

(i) The variety of rocks
(ii) The general topography of the area.
(iii) The amount and the distribution of annual precipitation
(iv) The vegetation cover.
(v) The discharge of the water in the stream
(vi) The stage of the river development
(vii) The cycle of erosion, i.e the time factor

 

The meandering of the river can occur in all types of terrains. It is more in regions having level surfaces with gentle slopes. Practically all the rivers in Northern Plains in India have developed meandering courses.

 

The Gomti river in Uttar Pradesh is a highly meandering stream. The course of the Ganga river in Allahabad and Varanasi has developed a highly meandering course.

 

Ox-bow Lake

 

In some meanders, the beds are highly curved and the arms are very close to each other.

In course of time, due to lateral erosion, the meandering loops become almost circular and come very close to each other. The strip of land between these two loops continues to become narrow till the river cuts through this strip and takes a straight course. Thus the circular meander or loop is left behind completely cut off from the main channel, forming an ox-bow lake.

 

The formation of the ox-bow lake is due to both erosion and deposition. Most of the rivers in Northern India have developed ox-bow type of Meanders. Vyanthala Lake in South India at Vynthala in Kerela is the only naturally formed oxbow lake in India.

 

Braided River

 

When a river carries an enormous amount of load, it is unable to carry it all the way to the mouth. This causes the river to divide into many networks of channels forming islands in the river channel. Such a river is known as a braided river. This river is very useful in navigation and transportation.

 

Questions

 

1. Which is the only naturally formed oxbow lake in India?
(i) Dal Lake
(ii) Loktak Lake
(iii) Chilika Lake
(iv) Vyanthala Lake

 

2. The river Meanders is in which country?
(i) China
(ii) India
(iii) U.S.A
(iv) Turkey

 

3. Which of the following processes are responsible for the formation of Meanders?
(i) Weathering and Deposition
(ii) Mass wasting and Deposition
(iii) Erosion and Mass wasting
(iv) Erosion and Deposition

 

4. Which landform is formed when a circular meander or loop is left completely cut off from the main channel?
(i) Braided rivers
(ii) Meander
(iii) Gorge
(iv) Ox-bow lake

 

5. What type of landform is formed when the river is divided into channels having islands?
(i) Meander
(ii) Ox-bow lake
(iii) Distributary
(iv) Braided rivers