Physical Landscapes RIVERS AQA GCSE key terms

Question 1

Landscape

Answer 1

An extensive area of land regarded as being visually and physically distinct.

Question 2

Abrasion

Answer 2

Rocks carried along by the river wears down the river bed and banks.

Question 3

Attrition

Answer 3

Rocks being carried by the river smash together and break into smaller, smoother and rounder particles.

Question 4

Cross profile

Answer 4

The side to side cross-section of a river channel and/or valley.

Question 5

Dam and reservoir

Answer 5

A barrier (made on earth, concrete or stone) built across a valley to interrupt river flow and create a man‐made lake (reservoir) which stores water and controls the discharge of the river.

Question 6

Discharge

Answer 6

The quantity of water that passes a given point on a stream or river‐bank within a given period of time.

Question 7

Embankments

Answer 7

Raised banks constructed along the river; they effectively make the river deeper so it can hold more water. They are expensive and do not look natural but they do protect the land around them.

Question 8

Estuary

Answer 8

The tidal mouth of a river where it meets the sea; wide banks of deposited mud are exposed at low tide.

Question 9

Flood

Answer 9

Occurs when river discharge exceeds river channel capacity and water spills out of the channel onto the floodplain and other areas.

Question 10

Flood plain

Answer 10

The relatively flat area forming the valley floor on either side of a river channel, which is sometimes flooded.

Question 11

Flood plain zoning

Answer 11

This attempts to organise the flood defences in such a way that land that is near the river and often floods is not built on. This could be used for pastoral farming, playing fields etc. The areas that rarely get flooded would therefore be used for houses, transport and industry.

Question 12

Flood relief channels

Answer 12

Building new artificial channels which are used when a river is close to maximum discharge. They take the pressure off the main channels when floods are likely, therefore reducing flood risk.

Question 13

Flood risk

Answer 13

The predicted frequency of floods in an area.

Question 14

Flood warning

Answer 14

Providing reliable advance information about possible flooding. Flood warning systems give people time to remove possessions and evacuate areas.

Question 15

Fluvial processes

Answer 15

Processes relating to erosion, transport and deposition by a river.

Question 16

Gorge

Answer 16

A narrow, steep sided valley, often formed as a waterfall retreats upstream.

Question 17

Hard engineering

Answer 17

Involves the building of entirely artificial structures using various materials such as rock, concrete and steel to reduce, disrupt or stop the impact of river processes.

Question 18

Hydraulic action

Answer 18

The force of the river against the banks can cause air to be trapped in cracks and crevices. The pressure weakens the banks and gradually wears it away.

Question 19

Hydrograph

Answer 19

A graph which shows the discharge of a river, related to rainfall, over a period of time.

Question 20

Interlocking spurs

Answer 20

A series of ridges projecting out on alternate sides of a valley and around which a river winds its course.

Question 21

Lateral erosion

Answer 21

Sideways erosion by a river on the outside of a meander channel. It eventually leads to the widening of the valley and contributes to the formation of the flood plain.

Question 22

Levees

Answer 22

Embankment of sediment along the bank of a river. It may be formed naturally by regular flooding or be built up by people to protect the area against flooding.

Question 23

Long profile

Answer 23

The gradient of a river, from its source to its mouth.

Question 24

Meander

Answer 24

A pronounced bend in a river.

Question 25

Ox-bow lake

Answer 25

An arc-shaped lake which has been cut off from a meandering river.

Question 26

Precipitation

Answer 26

Moisture falling from the atmosphere - as rain, hail, sleet or snow.

Question 27

Saltation

Answer 27

Particles bouncing down the river bed.

Question 28

Soft engineering

Answer 28

Involves the use of the natural environment surrounding a river, using schemes that work with the river’s natural processes. Soft engineering is usually much cheaper and offers a more sustainable option as it does not interfere directly with the river’s flow.

Question 29

Solution

Answer 29

Soluble particles are dissolved into the river.

Question 30

Channel straightening

Answer 30

Removing meanders from a river to make the river straighter. Straightening the river (also called channelising) allows it to carry more water quickly downstream, so it doesn’t build up and is less likely to flood.

Question 31

Suspension

Answer 31

Fine solid material held in the water while the water is moving.

Question 32

Traction

Answer 32

The rolling of boulders and pebbles along the river bed.

Question 33

Vertical erosion

Answer 33

Downward erosion of a river bed.

Question 34

Waterfall

Answer 34

Sudden descent of a river or stream over a vertical or very steep slope in its bed. It often forms where the river meets a band of softer rock after flowing over an area of more resistant material.