2.4. Sustainable management of coasts Flashcards
1
Q
How can coastal defences be categorised?
A
- Hard engineering
- Soft engineering
2
Q
Hard engineering
A
- Some physical structure has to be built and maintained
- Requires money, manpower and technology
- Protects only one part of the coast but creates problems elsewhere
- May cause harms to humans
3
Q
Soft engineering
A
- Involves proper planning management and use of the coast as well as encouraging human interference along the coast
- Involves educating people
- Environmentally friendly
4
Q
Examples of hard engineering
A
- Rip rap
- Gabion
- Groynes
- Sea wall
- Breakwater
- Revetments
5
Q
Rip rap
A
- giant boulders placed at the foot (bottom) of cliffs.
- designed to absorb the waves energy and protect the cliffs behind.
- can be effective, but does look ugly, may reduce access to the beach
- can be expensive
6
Q
Gabion
A
- boulders placed in cage
- can be installed quickly and again is fairly effective
- reduces access to the beach
- can be expensive
7
Q
Groynes
A
- designed to stop longshore drift
- protects only one part of the coast
- can be expensive
8
Q
Sea wall
A
- absorb wave energy
- sometimes they are recurved to direct the waves energy back out to sea => not effective
- can be expensive
9
Q
Breakwater
A
- Instead of breaking on the coast, waves, break on the breakwater
- are often found around the mouths of rivers and ports
- can disrupt shipping and animals
10
Q
Revetments
A
- similar to sea walls, but often built out of wood
- found at the foot of cliffs they are designed at absorb the waves energy
- require continuous efforts for maintenance
11
Q
Examples of soft engineering
A
- Dune stabilisation
- Cliff regarding
- Beach nourishment
- Beach drainage
- Managed retreat
12
Q
Dune stabilisation
A
- planting vegetation on the berm of the beach or on the dunes
- making them more stable (roots) and reducing the moisture content (root uptake)
13
Q
Cliff regrading
A
- makes cliffs less steep
- by reducing the angle you should reduce the undercutting and the risk of the cliff collapsing.
14
Q
Beach nourishment
A
adding more sand to the beach
15
Q
Beach drainage
A
removing some of the excess water to reduce stress on the cliff