Question

Look at the figure below and answer the questions:

1. What features are formed in the upper course of the river? What processes will play an important role?
2. Can you mark the location where a waterfall may formed?
3. Why is there a change in slope from A to B? How will it influence the flow of the river?
4. Which human activities can be conducted in the region around A and B?
5. In which area will the process of deposition overtake erosion?
6. Alluvial fans and deltas are both features formed due to deposition but at different locations. Identify their regions of formation and the reason behind their different locations.

Answer 1

1. Features formed in the upper course of the river are V-shaped valleys, gorges, and canyons, potholes, waterfalls, and rapids. Processes responsible for the formation of these landforms are - downcutting, drilling.
2. Waterfall may form at location 'A'
3. There will be a change in slope from A to B when the river enters the plains at the foothills of a mountain. The flow of the river decreases, the velocity reduces abruptly.
4. Around the region, A terraced farming can be practised. Around region B there is rich with alluvium brought down by the rivers, the plain is extensive and useful for agriculture. As the river widens around the source B, fishing and transportation are also found.
5. The deposition will be found at B and C
6. Alluvial fans will be formed at source 'B' at the foothills of the mountains, as there is a change in slope and the velocity of the river reduces abruptly. Now the river is unable to carry a heavy load. A delta will be formed at the mouth of the river. In this region, which is an extensively flat region, and where the sediments supply is high but velocity is low. So, the river deposits the sediments and branches out to meet the ocean or sea.