AQA Geography: Water on the Land Revision Notes

HideShow resource information
  • Created by: Anna Lucy
  • Created on: 06-11-12 22:23
Preview of AQA Geography: Water on the Land Revision Notes

First 377 words of the document:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
The process of heating where water changes from a liquid to a
Evaporation
vapour
Condensation The process by which cooling vapour turns into a liquid
Precipitation Water that falls to the Earth's surface. E.g. rain/snow
Surface runoff The movement of water over the land, possibly as a river
Transpiration Vegetation giving off water vapour from their leaves
Ground water Water that has sunk through the soil into the rocks below
Interception Water being prevented from reaching the surface by trees or grass
Surface storage Water held on the ground surface, e.g. puddles
Soil moisture Water held in the soil layer
Percolation Water seeping deeper below the surface
Through flow Water flowing through the soil layer parallel to the surface
Current upper level of saturated rock/soil where no more water
Water table
can be absorbed
Drainage basin Area which is drained by a river and its tributaries
Source The area which a river begins
Mouth Where a river ends its journey flowing into the sea or a lake
Tributary A smaller river that joins a larger river
Confluence The point at which two rivers join
The boundary between two drainage basins marked by a ridge of
Watershed
high land.
The total length of all the streams in the basin divided by the total
Drainage density
area of the basin.
Erosion The wearing away of the land
Hydraulic Action The force of the water erodes the river bed and banks
Occurs when the load of the river hits the bed and banks causing
Abrasion/Corrosion
bits to break off
The load of carried by the river knocks into other parts of the load
Attrition
so makes the material smaller
When the river flows over soluble rock (chalk or limestone) and
Corrosion/Solution
they dissolve and become part of the water.
Load Material carried by the river
Waterfall The sudden and often vertical, drop of a river along its cause
Gorge A narrow steep-sided valley

Other pages in this set

Page 2

Preview of page 2

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
Meander A bend in the river channel
A horseshoe or semi-circular area that represents the former
Oxbow lake
course of a river.
The flat area adjacent to the river channel, in the lower course.
Flood plain This created as a natural areas for water to spill onto when a river
floods
Raised banks along the course of a river. They are formed naturally
Levees
but can be artificially increased in height.…read more

Page 3

Preview of page 3

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
DRAINAGE BASIN
However the drainage basin is an open system and is part of the world's hydrological cycle.
A drainage basin, also known as a `River Basin' or as the `Catchment of a river,' is the area which is
drained by a river and its tributaries.
The drainage basin can be viewed as a system with inputs, stores and flows, and outputs.…read more

Page 4

Preview of page 4

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
UPPER
COURSE
The main
process of a river
in its upper course
is erosion ­ the
wearing away
of the land. There
are four types
of river
erosion;
Hydraulic Action
o The force of the water erodes the bed and banks
Abrasion
o Rocks carried along by the river wear down the river bed and banks.
Attrition
o Material carried by the river smashes together and breaks into smaller, smoother
and rounder particles.…read more

Page 5

Preview of page 5

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
Landforms in the Upper Course
V-shaped valleys and interlocking spurs
Rapids
Waterfalls
In the upper course of the river (near the source) vertical erosion is dominant and so the features
above are all formed by vertical erosion.
V-shaped valleys
A rivers discharge is low in the upper course and so the river
only has enough energy to erode downwards.
The valley sides are broken down through weathering.…read more

Page 6

Preview of page 6

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]…read more

Page 7

Preview of page 7

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
MIDDLE COURSE
As the course of the river approaches its middle course it flows over flat land, her lateral erosion is
dominant as the river swings in large meanders.
Meanders
Meanders and oxbow lakes are characteristics of the middle course of the river. The formation of
meanders leads to the development of oxbow lakes.
The outside of a meander is where erosion is dominant, because the water is moving fastest.…read more

Page 8

Preview of page 8

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
LOWER COURSE
Floodplains and levees are landforms formed by deposition in the lower course of the river.
Floodplains
In the lower course of a river channel, there is an area of flat land called a floodplain. This area gets
covered in water when the river overflows its banks. Floodplains are made up of alluvium, a fine
muddy material that is left behind after floods. Alluvium is sometimes called silt.…read more

Page 9

Preview of page 9

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
LONG AND CHANGING CROSS PROFILES
The long profile shows how the river changes in height along its course.
The steep reduction in height near the source gives way to a more gradual reduction further
downstream, giving a typical concave profile. The river has much potential energy near the source
due to the steep drop. Later on, this is replaces by energy from a large volume of water. However,
such a perfect long profile is rare.…read more

Page 10

Preview of page 10

Here's a taster:

Geography [TOPIC 3 ­ WATER ON THE LAND (RIVERS)]
FLOOD HYDROGRAPHS
A hydrograph shows how a rivers discharge changes over time in response to a rainfall event.
The rivers discharge increases until it reaches its peak discharge. Surface runoff is the first water to
reach the river and then throughflow.
The falling limb shows the speed at which the river returns to its normal (base) flow.
Lag time is the time between the maximum rainfall and the peak discharge.…read more

Comments

Kav

Thanks! Really helped me out ... it's exactly what we covered in school!

Similar Geography resources:

See all Geography resources »See all resources »