Rivers Flashcards
Types of erosion
Solution
Attrition
Abrasions
Hydraulic action
Erosion
The wearing away of rock and soul found along the river bed and banks
Solution
Soluble particles are dissolved
Abrasion
Rocks carried along by the river and scrapes along the river
Attrition
Rocks being carried by the river smash together and break into smaller, smoother and rounder
Hydraulic action
The force of the rivers against the banks can cause air to be trapped in cracks and crevices. The pressure weakens the banks and gradually wears it away
Transpiration
The movement of sediment along the river course
Types of transportation
Suspension
Traction
Solution
Saltation
Suspension
Fine, light material is carried along by the river
traction
large boulders and rocks are rolled along the river bed
solution
minerals are dissolved in the water. this is a chemical change
saltation
small pebbles and stones are bounced along the river bed
causes of flooding
what makes a flood happen?
heavy rainfall steep land built up areas cutting down trees lots of impermeable ground
effects of floods
what good and bad things do floods cause?
deaths home damaged people without access to drinking water risk of diseases spreading schools and hospitals difficult to get to bridges swept away transport is difficult farmland lost
responses to flooding
what did people do after the flood?
charities send aid governments of other countries send help/money people are evacuated to safety temporary homes set up clean drinking water provided to people bridges ands road repaired
hard engineering
physically changing the shape of the river or building structures to prevent flooding
embankments
they are mounds of earth built up at both sides of a river to increase the amount of water that the river can hold
flood walls
this are walls built along a river to protect vulnerable areas from water damage e.g housing
straightening and deepening the river channel
making rivers straight means that the water will flow more quickly through this part of the river, giving it less chance to fill up and flood. rivers can be made deeper in order for them to hold more water
dams
they are often built along the course of the river in order to control the amount of discharge. water is held back by the dam and released in a controlled way. this controls flooding. water is usually stored in a reservoir behind the dam
soft engineering
working with the natural environment to prevent flooding or flood damage
land-use zoning
this is when more important buildings are built far away from the river to prevent damage e.g. hospitals
whereas less important land such as football pitches are closer to the river as they will not be faced with flooding much
