Option B - Management Coastal Margins

Question 1

Coastal Management (hard)

Answer 1

to control natural processes

Question 2

Coastal management (soft)

Answer 2

working with nature

Question 3

sea walls

Answer 3

large scale concrete curves walls design to reflect wave energy - easily made in areas of high density, expensive (30-40 year lifespan)

Question 4

revetments

Answer 4

porous design to absorb wave energy - easily made and cheaper than sea walls - limited life span

Question 5

Gabions

Answer 5

rocks held in wire cages absorb wave energy - cheaper than sea walls and revetments but small scale solution

Question 6

Groynes

Answer 6

prevent longshore drift - relatively low cost and can easily be repaired but cause erosion on down-drift side and interrupts sediment flow

Question 7

Rock armour

Answer 7

Large rocks at base of cliff to absorb wave energy- cheap but unattractive and small scale- may be removed in storms

Question 8

Offshore breakwater

Answer 8

Reduce wave power offshore - cheap to build - disrupts local ecology

Question 9

Rock Strongpoints

Answer 9

to reduce longshore drift - low cost and easily repaired - disrupts sediment flow and erosion on down-drift

Question 10

Cliff drainage

Answer 10

removal of water from rocks in the cliff - cost effective - drains may become new lines of weakness and cliffs may produce rockfalls

Question 11

Cliff regrading

Answer 11

lowering of slope angle to make cliff safer - useful on clay but uses large amounts of land (not practical in heavy populated area)

Question 12

Vegetating the surface

Answer 12

increase interception and reduce overland run-off - low cost but may increase moisture content of soil and increase risk of landslides

Question 13

Off shore reefs

Answer 13

waste materials (old tyres) weighted down to reduce wave speed - low technology and cost effective but long term impact unknown

Question 14

Beach nourishment

Answer 14

Sand pumped from seabed to replace eroded sand - looks natural but expensive and short term solution

Question 15

Managed retreat

Answer 15

coastline allowed to retreat in certain places - cost effective and natural but unpopular

Question 16

“Do nothing”

Answer 16

accept that nature will win, cost effective but unpopular

Question 17

Coral reefs

Answer 17

“rainforests of the sea”- rich biodiversity. Coral reefs contain nearly a million species of plants and animals and about 25% of the world’s sea fish breed grow and spawn in coral reefs.

Question 18

Value of coral reefs

Answer 18

major biological and economic importance - 4000 species of fish and 800 reef building corals have been identifies. Protect coasts against erosion. generate large profits for some users - tourism generated by the great barrier reef = 4.6 Billion annually in Queensland alone. global value - fisheries tourism and coastal protection = 375 billion

Question 19

Managing coral reefs

Answer 19

give ecologically sensitive areas special status (marine protected). activities deemed as harmful (fishing drilling and mining) can then be restricted or banned. fishing vessels - remoteness makes it difficult to stop vessels entering illegally

Question 20

Mangrove Swamps

Answer 20

salt tolerant forests of trees and shrubs that grow in tidal estuaries and coastal zones. muddy water rich in nutrients from decaying leaves and wood home to great variety of sponges, worms, crustaceans, molluscs and algae. Mmangroves cover about 25% of the tropical coastline

Question 21

Managing Mangrove swamps

Answer 21

provide humans with many ecological services (fuelwood, charcoal, timber, thatching material, dyes, poisons and food such as shellfish). Many fish use mangrove swamps as nurseries and mangroves also provide protection from tropical storms. Many stakeholders interested (fishermen, farmers, conservationists, local residents and politicians)

Question 22

Management strategies

Answer 22

30 year cycle of planting and harvesting
restoration and afforestation
manages realignment (allowing mangroves to migrate inland)
generic protection of ecosystems

Question 23

economic exclusive zone

Answer 23

area in which a coastal nation has sovereign rights over all the economic resources of the sea, seabed and subsoil extending up to 200 nautical miles from coast - “sovereign” = having independent authority over a territory

Question 24

impact of EEZs

Answer 24

major impact on the management and conservation of ocean resources since they recognise the right of coastal states to “exploit, develop and manage and conserve all resources”

Question 25

competing claims in the arctic

Answer 25

the arctic sea ice has been melting at an accelerating rate for many years - opening up new potential trade routes and providing access to valuable oil and gas reservoirs. could hold up to 90 billion barrels of oil and vast amounts of natural gas. Five countries racing for this (Canada, Denmark, Norway, Russia and USA). also increased potential for fishing - planktonic animals such as small crustaceans and krill now abundant and feeding on smaller plankton that survive in Arctic winter. this supports larger cod population

Question 26

Dispute over the Arctic

Answer 26

Countries around the Arctic ocean are rushing to stake claims on the Polar Basin seabed and its oil and gas reserves made more tempting by rising energy prices.