• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

How A River Changes As It goes Downstream.

Extracts from this document...


How A River Changes As It goes Downstream A rivers course starts in the mountains or relatively highland area and ends up meeting the sea. As a river travels downstream it changes in many ways. Different features are made and different processes take place. These things take place in different stages of the river. There are 3 stages in total. The upper course, the middle course and the lower course. In the upper course, the start of the river is called the source. It is usually a small lake or spring. In the mountains there are also small tributaries that feed into the main river at the confluence. In this particular part of the course the width is small and the depth is very shallow. The channel gradient is very steep allowing the water to just trickle down the hill because it hasn't got enough water to flow. The velocity is also very minor. In this part of the course, erosion is the dominant process. The river may erode creating different features by any of the four erosion processes. ...read more.


The sharp boulders cut into the softer rock making the ground uneven and therefore the water flows more rapidly over the bumps. As the river flows downstream from the upper course to the middle course, the gradient over which it flows becomes less steep and the river is not as high above as its base level. The river also becomes wider and deeper. The river continues to erode vertically, but lateral or sideways erosion becomes more important. The middle course is where the most transportation takes place. There are again 4 types of transportation. Traction, which is when large boulders, simply roll along the riverbed. Saltation, which is when smaller pebbles, are bounced along the bed, picked up and dropped as river flow changes. Suspension, which is when the finer sand and silt particles are carried along suspended in the flow of water. The last one is solution, which is when calcium carbonate materials dissolve in water and can be carried along in the river flow. The transportation takes place in the lower course as well just like erosion does. ...read more.


The first one is connected with meanders. When the outer bend is eroded and the inner bend is deposited on an ox-bow lake is formed. The old meander is cut off and there is a straight channel. When the ox-bow lake dries up it is called a meander scar. Close to the estuary, which is where the river meets the sea, flood plains can often occur. A flood plain is a very flat area of land that lies next to the river. When floods occur the water spills over its banks and floods the plain. This land is very good for farming because there are lots of nutrients in the soil. One of the final features is where all the transported material gets deposited. This is in the mouth and it is called a delta. As more and more material gets deposited, a flat area of silt starts to build up. Sometimes in a delta the rain creates a small lagoon in the middle of it. Overall as a river travels downstream, the width increases, the depth increases, the channel gradient decreases, the valley sides obviously decrease and the pebbles, rocks and boulders decrease in size, become smoother and rounder. Sunday 6th October 2002 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Hydrology & Fluvial Geomorphology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Hydrology & Fluvial Geomorphology essays

  1. Study the downstream changes of Loughton Brook.

    The middle stage has meanders and ox-bow lakes. In the lower stage we find flood plains, levees and deltas. The River Channel The river channel consists of the river bed and the banks. A number of processes occur in a river channel which can explain the various landforms seen downstream.

  2. The river Gwaun: Investigating how the course of the river changes from the source ...

    However, the width still increases on the other side of the river where an ox-bow lake is visible, and because this riverbank is allowed to grow, as shown by the overhang formed at the riverbank, the width at Site 2 increases from that at Site 1.

  1. Does the river Alyn follow Bradshaw's model?

    Cross-sectional Area v Discharge (graph 16) - This showed a good positive correlation of 0.56. This isn't surprising as discharge is made up of cross-sectional area and velocity and so when cross sectional area increases there is only one other factor that can counteract it.

  2. Investigate how the velocity of rivers changes.

    This process is more likely in lowland areas by which time material will have broken up small enough to be carried in suspension. Corrosion is when acids in the river dissolve rocks, such as limestone, which form the banks and bed.

  1. Do the Characteristics of a river change downstream?

    I would expect the river channel at this point is V-shaped due to the water vertically eroding into the ground. This is known as vertical erosion and takes place in streams that occur on the upper course of a river.

  2. Geograpgy glendun river

    the upper course so it would take more energy to carry, as you go further down stream the load gets smaller and eventually there will be pebbles, this creates a high load amount as there are only pebbles and not boulders.

  1. Geography Coursework How Does Farming Change Between Bredon Hill and Birlingham? ...

    Then you can see the different levels of the soil. Land-use survey data recording sheet - Bredon Hill to Birlingham Categories Site A (G.R. = 948,408) Site B (G.R. = 944,413) Site C (G.R. = 942,420) Site D (G.R. = 939,434)

  2. As a group we have decided to look at the changes in a river ...

    Some drainage basins can be very large like the Mississippi which drains one third of the USA and others are small like the Strule. However the size of is less important than the drainage density. The drainage density is the total length of all the streams in the drainage basin divided by the area of the drainage basin.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work