RIVERS Flashcards
Hydrological Cycle
the movement of water within a drainage basin
Infiltration
Water moving from surface to soil
Throughflow
– downhill transfer of water through the soil layer to the river
Percolation
deep transfer of water through permeable rocks
Base/groundwater flow
very slow transfer of water through rocks
Depression Storage
when water is temporarily stored on the ground in the form of puddles
Interception
vegetation which absorbs and slows down water transfer
Confluence
Where 2 rivers meet
Water budget
Shows changes in water balance over the year
Recharge
When precipitation exceeds potential evapotranspiration, but soil is yet to reach its field capacity
Surplus
precipitation exceeds potential evapotranspiration and soils reach full field capacity, creating run-off
Utilization
when potential evapotranspiration exceeds precipitation but soil storage is yet to reach 0
Deficit
When soil storage reaches 0
4 zones of the water budget
Recharge, surplus, utilizations, deficit
How does basin size effect water transfer?
Small basin – rapid water transfer
How does Drainage density effect water transfer?
High density speeds up transfer
How does land use effect water transfer?
Urbanisation encourages rapid water transfer Interception
How does relief effect water transfer?
Steep slopes lead to water with a higher velocity
How does soil moisture effect water transfer?
Saturated soils lead to rapid overland flow
Abrasion
grinding effect on the bed as eroded rock particles scour the banks
Hydraulic action
Action force of the water
Cavitation
Tiny bubbles of air implode in cracks of the river bed
Attrition
when rock particles hit each other, smoothening edges – explaining why particles downstream are more likely to be smaller and rounder
4 types of river transportation
Solution, suspension, Bedload : (saltation) and (traction)
Solution
dissolve – e.g. calcium carbonate from limestone
Suspension
carried within the main body of the river – fine grained mud