1.c. Coastal sediment is supplied from a variety of sources.

Question 1

What are rivers to the coastal sediment budget?

Answer 1

Rivers are major sources of sediment input to the coastal sediment budget.

This is particularly true of coasts with a steep
gradient, where rivers directly deposit their sediments at the coast.

Sediment delivery to the shoreline can be intermittent,mostly occuring during floods.

Question 2

Origin of the sediment is the……

Answer 2

erosion of inland areas by water, wind and ice as well as sub-aerial processes of weathering and mass movement.

Question 3

Wave erosion is also the source of……

Answer 3

large amounts of sediment and makes a major contribution to coastal sediment budgets.

Question 4

Cliff 1

Answer 4

Cliff erosion is increased by the rising sea levels and amplified by storm surge events

Question 5

Cliff 2

Answer 5

The erosion of weak cliffs in high energy wave environments contributes as much as 70 percent in overall material supplied to beaches.

Question 6

Does longshore drift contribute to the coastal sediment budget?

Answer 6

Longshore drift can also supply sediment from one coastal area to another by moving it across the coast to adjescent areas

Question 7

How does offshore contribute to the coastal sediment budget?

Answer 7

Constructive waves bring sediment to the shore from offshore location and depositit it ( marine deposition) adding to the sediment budget. ( Same with tides and currents)

Question 8

(OFFSHORE) How does wind contribute?

Answer 8

Wind blows sediment from other locations including exposed sand bars, dunes elsewhere along the coast. This aeolian material is generally fine sand. ( wind has less energy than water, and cant transport large particles).

Question 9

Beach nourishment

Answer 9

When coastal sediment budget is in deficit, beach nourishment is one way equilbruim can be maintained.

This type of management has been adopted all over the world in order to protect costal lanscapes. Sediment can be brought via lorries and dumped+ spread out by bulldozers.

Sand and water can be pumped onshore via pipeline from offshore soucres. Low bunds hold the mixture in place while the water drains away and leaves the sediment behind

Question 10

Wind waves and longshore drift can…..

Answer 10

also remove sediment from the coastal sediment budget. By subracting the sediment lost by amounnt gained you can deterine if the sediment is in equilibrime, defit or surpluss