coastal environments

Question 1

what is weathering

Answer 1

the gradual breakdown of rock, in situ. It can be divided into 3 different types: mechanical, chemical and biological

Question 2

Give an example of each type of weathering

Answer 2

Mechanical: freeze-thaw
Chemical:oxidation
Biological: plant roots

Question 3

Four erosional processes:

Answer 3

hydraulic action, solution, abrasion, attrition

Question 4

what is hydraulic action

Answer 4

the power of the waves forces water into cracks in a cliff. this compresses the air in the cracks. when the wave retreats the compressed air blasts out forcing the rock apart and crack to widen.

Question 5

what is attrition

Answer 5

material carried by waves collide together causing them to become smaller and rounder over time.

Question 6

what is abrasion

Answer 6

the waves pick up sand and pebbles and hurl them at the cliff face, wearing the cliff away. also applies to sediment in rivers wearing banks away.

Question 7

how are headlands and bays formed

Answer 7

Formed from alternating bands of harder and softer rock. Less resistant rock is eroded faster, and more resistant is eroded less by the erosional processes, leaving headlands on either side of a bay.

Question 7

what is longshore drift

Answer 7

the zigzag movement of sediment along the coast, travelling diagonally onto the beach by swash and dragged back at right angles by backwash.

Question 7

what is sliding

Answer 7

an increase in water (e.g after heavy rain) reduces friction and increases weight causes material to become unstable and rapidly move downhill.

Question 8

what is slumping

Answer 8

whole segments of the cliff moving down, causing rotational scars (land is bumpy like stairs)

Question 9

how’s a spit formed

Answer 9

sediment carried by longshore drift is deposited where coast suddenly changes direction so the water is shallow and protected by the headland and spit slowly builds up

Question 10

how does vegetation protect the coast

Answer 10

it stabilises loose material and reduces erosion

Question 11

three examples of vegetation/structures that protect coast

Answer 11

sand dunes, mangroves and salt marshes

Question 12

formation of caves, arches, stacks and stumps

Answer 12

crack in cliff opens up and grows due to erosional processes. Cave becomes larger until it breaks through headland, forming an arch. Arch is eroded and forms a stack which is eroded further to a stump.

Question 13

where are sand dunes found

Answer 13

Further from the shore in areas where there’s lots of sand and high winds

Question 14

where are salt marshes found

Answer 14

mid-level mudflats that lie high above the high water mark.

Question 15

where are mangrove forests found

Answer 15

found in over 100 countries in subtropical and tropical climates

Question 16

Abiotic characteristics of the Great Barrier Reef

Answer 16

Developed in shallow tropical waters, on a very shallow continental shelf.
Beyond this is a steep 2,000m drop off
Average depth of just 35m
900 islands

Question 17

Biotic characteristics of the Great Barrier Reef

Answer 17

Largest living structure on the planet
3,000 individual coral reef
over 450 species of hard coral
symbiotic relationship between microscopic algae and coral
symbiosis between clownfish and anemones

Question 18

Threats to coral reefs

Answer 18

Development - increased tourism means more human activity in water, more fishing, pollution from development
Industrialisation - ports developed, lots of pollution, more fishing
Agriculture - deforested land accelerates soil erosion, pollutes the sea.
Invasive species - e.g. crown of thorn starfish
climate change - coral bleaching

Question 19

what is coral bleaching

Answer 19

When the temp of the water increases due to global warming, the small plants inside polyps can’t photosynthesise as effectively, so they are gotten rid of. Coral has lost its most important food source and starves. Flesh becomes clear and the white we see is the bones.

Question 19

name some stakeholders of the coast

Answer 19

• wildlife lovers
• fishermen
• divers
• tourists

Question 20

what are the 4 shoreline management plans

Answer 20

do nothing
managed retreat
hold the line
advance the line

Question 21

hard engineering definition and examples

Answer 21

building and using man-made, artificial structures to protect coastlines. Often expensive, short-term and unsustainable. Examples: groynes, gabions, rip rap, sea walls, revetments

Question 22

soft engineering definition and examples

Answer 22

managing erosion by working with natural processes. Sustainable and long-term (usually). Examples: beach replenishment, cliff regrading, ecosystem rehabilitation and revegetation and managed retreat

Question 23

Why is the Holderness Coastline subject to erosion

Answer 23

Geology of coast - most is till (clay) and glacial sand and gravel. Very soft material which can be eroded very quickly.

Question 24

Difference between weathering and erosion

Answer 24

weathering weakens rock whereas erosion actually breaks it off/ apart

Question 25

Why is Odisha Coast eroding so quickly

Answer 25

Rising sea levels means more flooding, frequent tropical cyclones and floods. Many mangroves which was coasts best protection were deforested

Question 26

what causes a storm surge and what damage does it cause

Answer 26

Strong winds which pushes sea water towards coast and causes high waves, which can damage sea defences and infrastructure.

Question 27

what causes a tsunami and what damage does it cause

Answer 27

mainly caused by earthquakes near or below ocean.
Damages infrastructure, lots of death, financial loss

Question 28

how does climate change cause coastal flooding and what are the impacts

Answer 28

causes thermal expansion and melting of land-based ice. impacts: storm surges pushed further in, flooding, loss of marshes and wetlands, erosion of beaches and coastal areas

Question 29

what is odisha’s management strategy

Answer 29

trying to plant and cultivate new mangrove forests