Flashcards in The drainage basin Deck (32)
- (1) system
- AKA (2) can be any size
- (3) within the global hydrological system
1 - open
2 - local hydrological system
3 - subsystem
Define 'drainage basin'
The area of land drained by a river and its tributaries
Name five factors that affect the drainage basin
How does climate affect the drainage basin?
Affects the rate of evaporation, precipitation and vegetation growth
How does soil affect the drainage basin?
Clay - impermeable due to particle size so stores water
Sand based - through flow and infiltration
How does geology affect the drainage basin?
Chalk and Sandstone allows aquifers as water soaks into them
Pervious (limestone) allows water to flow but not into the rock
Caves and stalagmites
How does relief affect the drainage basin?
Orographic rainfall affects run off as a steeper slope will reduce infiltration
Name four human impacts on the drainage basin
- Mega dams
How does deforestation affect the drainage basin?
Less interception so rain falls directly on the soil > compaction > less EVT
How does urbanisation affect the drainage basin?
Less infiltration capacity
How does agriculture affect the drainage basin?
Water needed for irrigation, pasture compact soil, arable removes nutrients and requires heavy machinery
How do mega damns affect the drainage basin?
Increased EVT and reduces water downstream
- (1)% destroyed in the last 50 years
- Trees are '(2)' act as carbon sinks
- (3)% of rainfall is recycled from trees
- (4)% of intercepted water is EVT
- Contains (5)% of the world's rainforest
1 - 20
2 - green lungs
3 - 50
4 - 75
5 - 60
How does the El Nino Southern Oscillation affect the Amazonia?
Droughts and forest fires
Why is run-off into the Amazon problematic?
Aquifer depletion and soil erosion
Name the only input of the drainage basin system
Name the five flows in the drainage basin system
Name four stores in the drainage basin system
Name the three outputs in the drainage basin system
When water flows through the soil by the force of gravity
Where is precipitation heaviest and why? What affects precipitation?
Tropics due to the Intertropical Convergence Zone and places that get monsoons
ITCZ - high solar radiation causes rapid convection of warm air
Also affected by continentality (distance from sea) and land relief
Why could precipitation act as a store? What affect does this have on precipitation distribution?
E.g. snow takes longer to form
Not evenly distributed across drainage basin
Name the seven fluxes (flows)
Direct run off
Saturated over land flow
Ground water flow
What affects interception?
- Size of the leaves (vary throughout the year)
- Deciduous (loses its leaves during the winter)
What affects infiltration? (mm/hr)
- antecedent soil moisture
- soil compaction
- slope angle
Name four factors that affects the volume of evaporation
- Hours of sun
- Air movement
Where is the Amazon River located?
Amazon river regime:
- (1)km long
- (2) km squared basin
- Snowmelt from the (3)
1 - 6,308
2 - 6 million
3 - Andes Mountain Range
Where is the Yukon river?
North America (Canada and Alaska)