SC - physical landscapes in uk Flashcards
What is the primary reason for coastal management in Swanage?
To protect the town from flooding and erosion
Swanage is economically viable for coastal defense works due to its developed coastline.
What are groynes and their purpose in coastal management?
Wooden barriers built at right angles to the coast to trap material from longshore drift
Groynes create larger beaches that absorb wave energy, reducing erosion rates.
What impact did the installation of new timber groynes in 2005-2006 have?
Reduced loss of beach material but caused narrower beaches further down the coast
The reduction in beach material movement leads to increased erosion in other areas.
What is the function of the concrete sea walls in Swanage?
To reflect waves back out to sea and prevent erosion to the cliff
Sea walls help protect the coastline but can create strong backwash effects.
What negative effect can sea walls have on beach sediment?
They create strong backwash that removes sediment from the beach
This can lead to lower beach levels over time.
What is beach replenishment?
Dredging sand and shingle from the sea bed and adding it to the beach
This process helps to widen the beach and reduce erosion.
When was the beach replenishment project carried out in Swanage?
Winter 2005-2006
The project involved adding sand and shingle to the upper parts of the beach.
What was the cost of the beach replenishment project in Swanage?
£5 million
This project is expected to need repeating approximately every 20 years.
True or False: Groynes can cause increased erosion in areas down the coast.
True
By stopping the movement of beach material, groynes can lead to narrower beaches elsewhere.
Fill in the blank: Concrete sea walls prevent ________ to the cliff.
[erosion]
They reflect waves but can lead to sediment loss from the beach.
what are some types of hard engineering?
groynes - wooden or rock structures built out at right angles into the sea
sea walls - concrete walls that are placed at the foot of the cliff to prevent erosion
rock armour - large boulders placed at the foot of a cliff they break the waves and absorb their energy
gabions - rock are held in mesh cages and placing areas affected by erosion
what are some types of soft engineering?
Beach nourishment- sand is pumped onto an existing beach to build it up
Managed retreat - the controlled flooding of low lying coastal areas of low value land
dune regeneration - grass planted on sand dunes and helps trapped sand to build them up
spits and bars
1 - longshore drift moves material along coast line
2- forms when material is deposited
3- overtime a bit developed a hook if window direction changes further out
4-waves cannot get past a spit which creates a sheltered area we lit is deposited and mudflats or saltmarshes form
What is physical weathering?
When rocks are porous or permeable
what is chemical weathering?
Certain types of rocks such as limestone and chalk that can be dissolved by slightly acidic rainwater or seawater
