GEOGRAPHY - Rivers Flashcards
What is the transportation method traction?
Large boulders roll along the river bed
What is the transportation method saltation?
Smaller pebbles are bounced along the river bed, picked up and then dropped as the flow of the river changes.
What is the transportation method suspension?
Finer sand and silt particles are carried along in the flow, giving the river a brown appearance.
What is the transportation method solution?
Minerals from rocks are dissolved into the water and carried along in the flow.
What is the upper course’s:
- Gradient?
- Discharge?
- Depth?
- Channel shape?
- Velocity?
- Features?
- Steep gradient
- Small discharge
- Shallow depth
- Narrow steep sides
- Relatively fast speed
- Waterfalls, gorges, interlocking spurs
What is the middle course’s:
- Gradient?
- Discharge?
- Depth?
- Channel shape?
- Velocity?
- Features?
- Less steep gradient
- Large discharge
- Deeper depth
- Flat, steep sides
- Fast flow
- Meanders, ox-bow lakes, Floodplains
What is the lower course’s:
- Gradient?
- Discharge?
- Depth?
- Channel shape?
- Velocity?
- Features?
- Shallow gradient
- Very large discharge
- Deep depth
- Flat floor, gently sloping sides
- Very fast flow
- Levees, Floodplains, Estuaries, deltas
What physical factors affect discharge levels, the rising/falling limb and the lag time on a hydrograph?
Geology
Soil type
Vegetation
Slopes
Drainage basin shape
Antecedent conditions
Which hard engineering methods can be used to manage floods?
Embankments
Flood walls
Dams and reservoirs
Flood barriers
Channel straightening
Which soft engineering methods can be used to manage floods?
River restoration
Washlands
Floodplain retention
Afforestation
What’s the difference between quantative methods and qualitive methods to collect data?
Quantative methods record data that can be measured as numbers whereas qualitive methods record descriptive data like how people feel.
What is meant by discharge?
The volume of water in the river measured in cubic metres per second.
What is the equation for discharge?
Discharge = area (cross-sectional x velocity)
What are some reasons why flooding is increasing in the UK?
Population growth
Climate graph
Less green space
What are two ways that human activities can affect storm hydrographs?
Urbanization can decrease the rate of infiltration in areas where humans have settled
Storm drains can be built that take rain water directly into the river which can increase discharge levels.
