sediment cells

Question 1

what are sediment cells

Answer 1

sediment cells are sections of the coastline which consist of zones of erosion, zones of transport and zones of deposition. sediment cells are mostly self-contained as they function separately from one another, there are geographically bounded by significant disruptions to the coastline

Question 2

what is dynamic equilibrium

Answer 2

it is the maintenance of a balance in a natural system, despite it being in a constant state of change.

Question 3

what can interrupt dynamic equilibrium

Answer 3

by human interventions or by natural variations

Question 4

what is dynamic equilibrium in relation to sediment cells

Answer 4

where the inputs and outputs are balanced

Question 5

what are coastal inputs

Answer 5

marine: waves, tides, salt spray
atmosphere: sun, air pressure, wind speed and direction
humans: pollution, recreation, settlement, defenses

Question 6

what are coastal outputs

Answer 6

-ocean currents
-rip tides
-sediment transfer
-evaportation

Question 7

what are coastal stores

Answer 7

-beaches
-sand dunes
-spits
-bars and tombolos
-headlands and bays
-nearshore sediment
-cliffs
-wave-cut notches
-wave-cut platforms
-caves
-arches
-stacks
-stumps
-salt marshes
-tidal flats
-offshore bands and bars

Question 8

what are the transfers in the coastal system

Answer 8

they are the processes that link the outputs, inputs and stores in the coastal system:
-wind-blown sand
-mass-movement processes
-longshore drift
-weathering
-erosion
-transportation
-deposition

Question 9

what are the sources of energy in the coastal system

Answer 9

-wind
-gravitational
-flowing water

Question 10

what is a negative feedback loop

Answer 10

this lessens any chance which has occurred within the system

Question 11

what is a positive feedback loop

Answer 11

this exaggerates the change making the system more unstable and taking it away from dynamic equilibrium

Question 12

what are the sediment sources along the coast

Answer 12

-rivers
-cliff erosion
-wind
-glaciers
offshore
-longshore drift

Question 13

how are rivers a sediment store

Answer 13

-most of the sediment in the coastal zone is a result of an input from rivers
-sediment may be deposited in estuaries which are areas where the river flows into the sea
-the sediment is then transported throughout the coastal system by waves, tides and currents

Question 14

how is cliff erosion a source of sediment

Answer 14

it is a very important in areas with unconsolidated cliffs which would erode easily.

Question 15

how is wind a source of sediment

Answer 15

-wind is a coastal energy source which would cause sand to be blown up or along the beach
-sediment is transported by wind in circumstances like sand dunes

Question 16

how are glaciers a source of sediment

Answer 16

-in coastal systems like in antarctica, greenland, alaska and patagonia the glaciers flow directly into the ocean depositing sediment which was stored in the ice

Question 17

what are offshore sediment stores

Answer 17

sediment is transferred to the coastal zone when waves, tides and currents erode offshore sediment sinks such as offshore bars, storm surges and tsunamis may also transfer sediment into the coastal zone

Question 18

how is longshore drift a source of sediment

Answer 18

because sediment is moved along the beach due to prevailing winds which would alter the direction of the waves, this allows sediment to be transported from one section of coastline to another section of coastline

Question 19

what are sediment budgets

Answer 19

sediment budgets would use data of inputs, stores and transfers to assess the gains and losses of sediment within a sediment cell

Question 20

what is the littoral zone

Answer 20

it is the area of land between the cliffs or dunes on the coast and the offshore areas that is beyond the influence of the waves.

Question 21

why is the littoral zone always changing

Answer 21

-short term factors = tides and storm surgers
-long term factors= changes in sea level and human intervention