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IB Oceans and their Coastal Margins

IB Oceans and their Coastal Margins. B3 – The Value of Oceans. Resource Base. World’s oceans represent a valuable resource base for the planet. Biotic – relating to living organisms Abiotic – non-living chemical and physical factors. Resources.

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IB Oceans and their Coastal Margins

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  1. IB Oceans and their Coastal Margins B3 – The Value of Oceans

  2. Resource Base • World’s oceans represent a valuable resource base for the planet. • Biotic – relating to living organisms • Abiotic – non-living chemical and physical factors.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Question Describe the issues involved in the management of fish as a resource?

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