l05 value of oceans
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IB Geography: Oceans and their Coastal Margins
IB Oceans and their Coastal Margins
B3 – The Value of Oceans
IB Geography: Oceans and their Coastal Margins
• World’s oceans represent a valuable resource base for the planet.– Biotic – relating to living organisms– Abiotic – non-living chemical and physical factors.
Resource Base
IB Geography: Oceans and their Coastal Margins
Resources• The world’s oceans provide many products
that are useful for humans.• Accessing resources is more difficult in the
deep oceans than in the shallow continental shelves.
• The margins of the oceans have the greatest demands on them.
• As technology develops and cost structures change even the deepest and remote ocean areas are seen as being able to provide resources for human use.
IB Geography: Oceans and their Coastal Margins
Fishing• Most useful biotic resource that the ocean
provides for humans is fish.• Fish supplies 16% of the world’s protein to
humans.• Fishing is conducted at a wide range of scales
from individual people casting nets to large trawlers that operate like factories.
• Most fish are used for human consumption.• Other use of fish are feeding animals or provide
oils as raw materials for industrial processes.
IB Geography: Oceans and their Coastal Margins
IB Geography: Oceans and their Coastal Margins
Transport• Although people tend to travel long distances
by Air humans still use oceans for transport.• Long-distance shipping is widely used to
transport cargo in various types of ships including bulk oil tankers and container ships.
• Oceans are also used for communications as long-distance telephone, internet and data cables are laid across the ocean floor.
IB Geography: Oceans and their Coastal Margins
Tourism• An increasingly important use for oceans as a
resource.• Most tourism related to oceans occurs on the
margins, such as beaches and the shallow waters of the continental shelves.
• Some cruise liners carry passengers across the oceans between continents.
IB Geography: Oceans and their Coastal Margins
Abiotic Resources: Minerals• Ocean resources are increasingly being used as a
source for minerals.• It is more difficult and more expensive to mine
the oceans than the land.• If the resource is significantly valuable it justifies
the high cost.• Unfortunately mining in the oceans often causes
destruction of natural ecosystems.• When dredging occurs the ocean floor is totally
destroyed wiping out all marine habitats and breeding grounds.
IB Geography: Oceans and their Coastal Margins
Fishing• Traditional fishing methods were defined to
obtain food for subsistence purposes.• Today fishing within most LEDCs takes only the
quantities of fish needed for food in the local community.
• Under traditional fishing fish remains a renewable resource.
IB Geography: Oceans and their Coastal Margins
Commercial Fishing• Commercial fishing provides an incentive to catch as many
fish as possible to make as much money as possible.• The fishing industry has a great difficulty conserving
resources in part because fish can move across boundaries.• Within any country their can be enforcement of rules
about size of fish and bag limit.• Actions can help to conserve fish stock in estuaries and
coastal waters when there are sufficient inspectors to police regulations.
• Destruction of breeding habit may be counteracting conservation measures.
IB Geography: Oceans and their Coastal Margins
Fishing Stocks• Fish may move great distances during their life cycle
and this will mean crossing the boundaries of countries’ control.
• Territorial waters now extend some 320 kilometers from the shore and that means there is an overlap between many countries; or dispute where the line should be placed.
• Many countries enter other countries territorial waters and remove food and other sources of food.
• Patrolling can go some way to seeing that conservation measures are observed.
IB Geography: Oceans and their Coastal Margins
Dwindling Fish Stocks• When fishermen are taking undersized fish stocks near an
ocean border they are depleting breeding stock on both sides.
• Much more efficient techniques have been developed in recent years:– Air and radar surveillance to locate fish schools.– Larger, faster, better equipped factory ships to process
and preserve the catch.– Better netting techniques that often require the team
work of a number of fishing boats.
IB Geography: Oceans and their Coastal Margins
Increasing Fishing• As well as fishing becoming more intensive the size
of the world fishing fleets grew enormously.• Fish can now be caught in quantities that threaten
the survival of species.• Drift net is still being used by fishers from some
countries despite being banned in international agreements.
• The drift net is almost invisible and snares virtually everything that is unluckily enough to swim into it.
• The drift net cannot exclude protected species.
IB Geography: Oceans and their Coastal Margins
Special Fish• There are special markets for particular fish, such
as tuna in Japan or the coral trout in Hong Kong.• The price that fishers can obtain encourages them
to take greater risks of breaching territorial waters.
• Coral trout has been taken from the protected marine park of the Great Barrier Reef to appear later in Hong Kong restaurants as the result of illegal fishing.
• The price that people are willing to pay influences whether conservation will be successful.
IB Geography: Oceans and their Coastal Margins
Conservation of Fisheries• Conservation measures are only having a minor
impact.• Trend in marine fish catches has been downwards
since about 1970 – though there is a greater success in catching what fish are actually there.
• Traditional fish sought by the industry are over exploited.
• Size of the catch is being maintained by some non-traditional species such as sprat or Pollock.
• This will allow the size of the yield to be maintained though not through active conservation.
IB Geography: Oceans and their Coastal Margins
Whaling• Breaches of restrictions on whaling receive more
publicity than the steep reductions in the stocks of fish.
• Conservation of Whaling has been successful in terms of conservation.
• Japan and Norway still do not recognise some international agreements.
• Numbers of whale species have shown a steady increase in their last two decreases.
• Many places they contribute to ecotourism as people are fascinated by them.
IB Geography: Oceans and their Coastal Margins
QuestionDescribe the issues involved in the management of
fish as a resource?
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