Flooding Flashcards
What’s flooding
A flood occurs when a river has too much water in its channel and it spills into the surrounding land
Causes of flooding
Human and physical
Physical causes of flooding
Heavy rainfall
Long periods of rain
Snow melt
Human causes of flooding
Deforestation and urbanisation
Deforestation
Removing trees
What is deforestation harmful?
It reduces the amount of water intercepted by trees and increases run off and therefore increases the amount of water in the river
Urbanisation
increase in the proportion of people living in towns and cities.
Why is urbanisation harmful?
Towns and cities don’t let water seep through it. It’s impermeable
Meaning of impermeable
not allowing fluid to pass through.
What does leaves act as?
An umbrella that stops rain from hitting the ground
What happens to the water on the leaves?
They evaporate and don’t reach the ground
What do roots do?
They take up water and reduce the amount of water reaching the river
They also slow down the movement of water in the soil
Ways floods can be prevented?
Afforestation
Dredging river channels so they can hold more water
Flood embankments
Afforestation
Plating trees in the river basin
How is afforestation helpful??
They act as a break from rainfall and reduce the amount of rain hitting the ground
