The Coastal Sediment Budget

HideShow resource information
What is important to know in order to manage a coastline?
How much sediment is available, where it comes from, where it is stored and how it leaves a particular coastal section.
1 of 25
What are these factors reffered to as?
The sediment budget.
2 of 25
Name an example of a 'soft rock coastline'.
Barton on Sea.
3 of 25
What is the major terrestrial supplier of sediment at Barton on Sea?
Cliffs (cliff retreat).
4 of 25
What is the dominant supply of sediment in Bangladesh?
Fluvial sediment.
5 of 25
Name some outputs to the coastal system.
Longshore drift (LSD), loss to offshore, transfer to sediment stores down the coast.
6 of 25
Name two examples of anthropogenic losses.
Beach mining, dredging.
7 of 25
What else can upset the sediment balance?
Human actions- building dams, hard engineering coastal defences.
8 of 25
Why do these upset the balance?
Inputs decline, it produces a net loss of sediment to the budget, accelerates erosion.
9 of 25
How can the sediment budget be balanced after this?
Beach feeding or nourishment.
10 of 25
How many main sediment/littoral cells are there in Wales? Where are their boundaries?
3- St Davids Head, Bardsey Sound, Great Orme Head.
11 of 25
Where does the movement of sand/ shingle by littoral drift/ longshore drift occur?
In discrete, functionally separate cells.
12 of 25
How many major cells are there in England and Wales?
11- they all contain smaller sub-cells.
13 of 25
What is a major cell?
A length of coastline and its associated nearshore area within which the movement of coarse sediments is largely self- contained.
14 of 25
Why are littoral cells described as open systems?
Because sediment cells are functional systems as there is some movement across longshore drift divides.
15 of 25
Where do sediment sinks/stores occur?
Where sediment transport paths meet.
16 of 25
In which state does a coast aim to exist?
Equilibrium.
17 of 25
What does this mean?
The amount of energy entering a coastal system is equal to the energy dissipated (going out).
18 of 25
What are the three types of equilibrium?
Steadt state equilibrium, meta-stable equilibrium, dynamic equilibrium.
19 of 25
What is a steady state equilibrium?
Where variations in energy and the morphological response do not deviate far from the long term average.
20 of 25
Give an example of this.
When the cliffs receive more or less the same atmospheric and marine energy (wind and waves), the profile of the cliff tends to stay the same from year to year, especially for resistant rocks.
21 of 25
What is a meta-stable equilibrium?
Where an environment switches between two or more states of equilibrium, stimulated by some sort of trigger.
22 of 25
Give an example of this.
The actions of high energy events such as tsunamis can remove a whole beach in hours. Or a human actions such as the construction of a large breakwater or offshore dredging.
23 of 25
What is a dynamic equilibrium?
When the equilibrium conditions change but in a gradual manner over a longer time period.
24 of 25
Give an example of this.
Response of coasts to eustatic and isostatic changes.
25 of 25

Other cards in this set

Card 2

Front

What are these factors reffered to as?

Back

The sediment budget.

Card 3

Front

Name an example of a 'soft rock coastline'.

Back

Preview of the front of card 3

Card 4

Front

What is the major terrestrial supplier of sediment at Barton on Sea?

Back

Preview of the front of card 4

Card 5

Front

What is the dominant supply of sediment in Bangladesh?

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Geography resources:

See all Geography resources »See all Coastal environments resources »