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Coastal Enviroments (Landforms (Erosional Landforms (Cliffs (Shaped due to…
Coastal Enviroments
Landforms
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Spits
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extended stretch of beach material that projects out to sea and is joined to the mainland at one end
Created by prevailing winds, causing longshore drift
Erosional Landforms
Cliffs
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Soft rock, eg sand and clay, erodes easily to create gently sloping cliffs
Hard rock, eg chalk, is more resistant and erodes slowly to create steep cliffs.
The process of cliff erosion
Weather weakens the top of the cliff
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The sea attacks the base of the cliff forming a wave-cut notch.
The notch increases in size causing the cliff to collapse
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The backwash carries the rubble towards the sea forming a wave-cut platform.
The process repeats and the cliff continues to retreat.
Caves occur when waves force their way into cracks in the cliff face. The water contains sand and other materials that grind away at the rock until the cracks become a cave.
The arch will gradually become bigger until it can no longer support the top of the arch. When the arch collapses, it leaves the headland on one side and a stack (a tall column of rock) on the other.
The stack will be attacked at the base in the same way that a wave-cut notch is formed. This weakens the structure and it will eventually collapse to form a stump
Management
Hard engineering
Groynes
Prevents the movement of beach material along the coast by longshore drift. But it can be seen as ugly and it is costly to build and maintain.
Sea Wall
Protects base of cliffs, land and buildings against erosion. However it is expensive to build and the cost of the maintenance is high.
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Soft engineering
Managed retreat
Areas of the coast are allowed to erode and flood naturally. Usually this will be areas considered to be of low value - eg places not being used for housing or farmland.
Beach mourishment
This replaces beach or cliff material that has been removed by erosion or longshore drift.The main advantage is that beaches are a natural defence against erosion and coastal flooding.It is a relatively inexpensive option but requires constant maintenance to replace the beach material as it is washed away.
Conflicts of interest
There are many different groups of people who have an interest in how coastal areas are managed. These include:
local residents
environmental groups
developers
local councils
national governments
tourist boards
National Park Authorities
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