1C: Physical Landscapes in the UK - Rivers Flashcards
Define interception
When raindrops are prevented from falling directly onto the soil surface by the presence of a layer of vegetation
Define infiltration
The passage of water into the soil
Define percolation
The downward movement of water through the rocks, eventually this water becomes groundwater
Define throughflow
Water moving down hill beneath the surface of the soil (it moves gradually through the tiny air spaces between the soil particles)
Define groundwater
Water that collects in rocks deep underground
Define the water table
The line which marks the upper limit of the groundwater (below this line the rocks are saturated with groundwater)
Define erosion
The wearing away and removed of material by a moving force, such as a flowing river
Define lateral erosion
The river erodes the banks of the river. This makes the channel wider
Define vertical erosion
The river cuts down vertically eroding the river bed. This often forms V-shaped valleys
Define hydraulic action
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 them down
Define abrasion
Rocks carried along by the river wear down the river bed and banks
Define attrition
Rocks being carried by the river smash together and break into smaller, smoother and rounder particles
Define solution
Soluble particles are dissolved by the river water
Define traction
Heavy rocks and boulders are rolled along the river bed. Happens most in times of flood when the river has more energy
Define saltation
Small stones and pebbles are bounced along the river bed. It can take place when the river energy is lower