Coastal management Flashcards
Selective management
Flooding and erosion of coastlines can have severe impacts, so management is focused on protecting homes, businesses and the environment.
Money is limited so choosing how and which places are defended is based on cost-benefit analysis.
Large settlements and industrial sites are generally favoured over isolated or small settlements.
Hold the line
Maintain existing coastal defences
Advance the line
Build new defences further out to sea than the existing line of defence.
Do nothing
Build no defences at all and deal with erosion and flooding as it happens.
Managed realignment
Allows the shoreline to move but manage retreat so it causes least damage.
e.g. breaching an existing defence and allowing the sea to flood the land behind. Overtime vegetation will colonise the land and it will become marshland.
Revetments
Slanted structures built at the foot of cliffs, made from concrete, wood or rocks. They cause waves to break, absorbing their energy and preventing cliff erosion.
They are expensive to build but relatively cheap to maintain.
However, they create a strong back wash which erodes underneath them.
Sea wall
Expensive to build and maintain.
They create a strong back wash which erodes underneath them.
Gabions
Rock filled cages, usually arranged in ‘walls’ at the foot of cliffs. They are cheap but ugly.
Riprap
Boulders piled up along the coast that absorb way energy and reduce erosion. They are fairly cheap but can shift during storms.
Groynes
Fences that trap material transported by longshore drift. They are quite cheap but can starve areas down drift of sand.
Breakwaters
Concrete blocks or boulders deposited off coast. They force waves to break, reducing their power before they reach the shore. They are expensive and can be damaged during storms.
Beach stabilisation
This is done by reducing the slope angle and planting vegetation, or by sticking old tree trunks in the beach to stabilise the sand.
Dune regeneration
Restoring or creating sand dunes are they act as a barrier between sea and land.
Land use management
e.g. using wooden walk ways and fencing off areas to prevent vegetation on sand dunes from being trampled on.
Marshland
Planting appropriate vegetation in mud flats to stabilise sediment.
Hard engineering
Involves built structures.
Expensive and disrupts natural processes.
Soft engineering
Cheaper and is designed to integrate with the natural environment. Creates important habitats like marshland and sand dunes.
More sustainable as it has low environmental impacts and economic costs.
Shore line management plans
A plan is devised for each sediment cell on how it should be managed, with the aim of protecting important sites without causing problems elsewhere.
All authorities in one cell cooperate in coming up with an SMP.
Integrated coastal zone management
Considers all elements of the coastal system when coming up with a strategy. (land, water, people, economy).
It aims to protect in a relatively natural state, whilst allowing people to use and develop it in different ways.
The environment is seen as a whole (water and land)
It considers fishing, industry and tourism
Various levels of authority have an input.
Dynamic- subject to change based on the demands of the area and the environment.
