coastal management Flashcards
what is soft engineering?
using natural systems for coastal defence, such as beaches, dunes and salt marshes which can absorb and adjust to wave and tidal energy
What is hard engineering?
making a physical change to the coastal landscape using resistant materials, like concrete, boulders, wood and metal
What are hard engineering methods?
Sea walls Rock armour Gabions Revetments Groynes Cliff fixing Offshore reefs Barrages
What are disadvantages to hard engineering?
structures can be expensive to build and to maintain
Defence in one place can have consequences for another area of the coast
Structures spoil the look of the landscape
What are sea walls?
Throw the waves back out into sea into the path of the next incoming wave
They provide a physical barrier to flooding
What is rock armour?
large boulders dumped in front of a cliff or sea wall to take full force of the waves
They have gaps for the water to filter through and a large surface area
Energy is taken by the rocks moving by the large waves
What are gabions?
smaller boulders contained in steel wire cages which can be joined together
What are revetments?
concrete wooden structures placed across a beach to take full force of wave energy
What are groynes?
wooden, stone or steel breakwaters at right angles to control longshore drift.
They trap sediment to create higher and wider beaches. They will also break up the waves.
What is cliff fixing?
driving iron bars into the cliff face to stabilise it and absorb wave power.
What are offshore reefs?
forces the waves to break offshore which reduces the impact on the base of the cliffs
What are barrages?
large structures built to prevent flooding on major estuaries.
acts as a dam
What is beach nourishment?
replaces material that has been lost through longshore drift
What is dune regeneration?
replant venerable areas with plants
selective grazing
restricting access
providing boardwalks for tourists
What is managed retreat?
developing the exposed land with salt marshes
