How Does A River Change From Upper To Lower Course?

How does a river change along its course?

As the river moves from the source to the mouth – both the depth of the river and the width of the river will both increase.

The load of a river will also change as it is transported and eroded along the river’s profile.

As a result, the size and shape of stones will change as they journey through the river profile..

Why is the flow of a river fastest in the lower course?

The river has more energy and the volume amount of water is high. 2) In the lower course there is more lateral (sideways) erosion. … The river has less friction to overcome which means that the river can flow faster.

Which part of a river flows the fastest?

The current is faster at a place where the bottom of a river is steep. A place where water flows fast in a river is where the width is narrow and the bottom steep. An example of such a river would be in a gorge of the upper reaches. Usually the speed of river water is fastest in the upper reaches.

Why does the flow of a river slow down near its mouth?

As a river flows, it picks up sediment from the river bed, eroding banks, and debris on the water. … The river slows down at the mouth, so it doesn’t have the energy to carry all the silt, sand, and clay anymore. These sediments form the flat, usually triangle-shaped land of a delta.

Why do rivers change shape?

Sediment flowing in the water can cut deeply into the bedrock. Over a long time, stream abrasion can cause great changes in the shape of a stream or river and Earth’s surface. In this investigation, students examine models of river erosion. … They see that as sediment is eroded, the shape of the stream changes.

What is middle course of a river?

The middle course of a river is found on gently sloping land, and is typically identified by its meandering path – the sweeping side to side curves. The middle course has two main features – meanders and ox-bow lakes.

Why is a river wider at its mouth than at its source?

It’s well known that rivers increase in size as they transport water from their source in their headwaters to the mouth. The river channel becomes wider and deeper and as a result its cross-sectional area increases. … In the upper course of the river bedload is larger and more angular.

What is the start of a river called?

The place where a river begins is called its source. River sources are also called headwaters. Water from Lake Itasca, Minnesota, dribbles down these rocks to form the source of the Mississippi River. The place where a river begins is called its source.

Where is the lower course of a river?

In the lower course, the river has a high volume and a large discharge. The river channel is now deep and wide and the landscape around it is flat. However, as a river reaches the end of its journey, energy levels are low and deposition takes place.

What is the difference between the upper course and the lower course of a river?

Upper course river features include steep-sided V-shaped valleys, interlocking spurs, rapids, waterfalls and gorges. Middle course river features include wider, shallower valleys, meanders, and oxbow lakes. Lower course river features include wide flat-bottomed valleys, floodplains and deltas.

Why is the lower course of a river deeper?

Lower course of a river The volume of water in a river is at its greatest in the lower course. This is due to the contribution of water from tributaries. The river channel is deep and wide and the land around the river is flat. Energy in the river is at its lowest and deposition occurs. .

What happens in the upper course of a river?

In the upper course of a river gradients are steep and river channels are narrow. … When a river runs over alternating layers of hard and soft rock, rapids and waterfalls may form. Waterfalls commonly form where water rushes down steep hillsides in upland areas and quickly erodes the rocks.

Is the upper course of a river deep?

Upper course – this is where the river starts and is usually an upland area. Slopes are steep – this can increase the velocity of the river after heavy rainfall, when discharge is high. The river channel is narrow and shallow here.

What does the long profile of a river show you?

A long profile is a line representing the river from its source (where it starts) to its mouth (where it meets the sea). It shows how the river changes over its course. … The river’s load is large in the upper course, as it hasn’t been broken down by erosion yet.