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Key terms Key termDefinition Coral reefA large area of coal, supporting a wide range of marine life. OverfishingFishing a large amount of a species, not.

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Presentation on theme: "Key terms Key termDefinition Coral reefA large area of coal, supporting a wide range of marine life. OverfishingFishing a large amount of a species, not."— Presentation transcript:

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2 Key terms Key termDefinition Coral reefA large area of coal, supporting a wide range of marine life. OverfishingFishing a large amount of a species, not allowing stocks to recover. Blast fishingPlacing explosives in the water, killing or stunning fish and allowing them to float to the surface. Trawler fishingDragging nets along the sea bed to catch large amounts of fish. Food webA system of interlinked food chains. Primary producerThe species at the bottom of a food chain. Often vegetation. ConsumerA species which consumes (eats) a species lower down the food chain. Ocean nutrient cycleThe transfer and store of nutrients in the ocean. Dead zoneAn area of ocean with little life, due to pollution or siltation. SiltationWhen sediment is deposited, usually from rivers, into the ocean, suffocating marine plant species. Ocean circulationThe global movement of cold and warm currents in the oceans. Continental shelfThe area of seabed around a large land mass where the sea is relatively shallow compared with the open ocean. Fishing quotasLimits on the amount of fish that can be caught in a given period of time.

3 Key facts: Distribution of coral reefs Generally located between the Tropic of Cancer and Tropic of Capricorn Coral reefs need: Shallow water of under 25 metres Warm ocean temperatures between 24 and 26 °C To be away from river mouths

4 Key facts: Goods and services provided by coral reefs GOODS: Food (fish and shellfish) Fish for aquarium trade Medicine source Lime for building materials Jewellery GOODS: Food (fish and shellfish) Fish for aquarium trade Medicine source Lime for building materials Jewellery SERVICES: Shoreline protection (natural storm barrier) Tourism Education and research SERVICES: Shoreline protection (natural storm barrier) Tourism Education and research

5 Key facts: Food chains and food webs

6 Key facts: The ocean nutrient cycle This waste ammonia is converted back into nitrates by nitrogen fixing bacteria. Deep-ocean (benthic) bacteria produce nitrogen from decomposing organic matter on the ocean floor Ocean plants take in nutrients, containing nitrates Waste products from fish, containing ammonia Dead fish and other ocean species sink to the ocean floor Fish and other ocean species take in nitrates when they eat submerged plants and algae

7 Key facts: LOCAL threats to coral reefs Damage from blast and trawler fishing Coral mining for building materials Pollution from sewage and oil spills (tourism can increase sewage levels from hotels) Storms can damage coral Siltation – suffocates coral. Sediment is washed into oceans from rivers. Can lead to areas known as ‘dead zones’ Removal of mangroves can increase siltation Divers can damage coral Damage from boat anchors Eutrophication from farms further inland

8 Key facts: Climate change effects on oceans 1.Changes to circulation of ocean currents, affecting distribution of heat around the world 2.Warming ocean water – can lead to coral bleaching 3.Ocean acidification – threats to species such as sea butterflies, affecting food webs. Also, acidic water can kill coral 4.Sea level rise – floods low-lying islands such as Tuvalu. Also, water can become too deep for coral to survive. 5.Species migration – affecting food webs You will need to use your book to explain these in more detail.

9 Key facts: Managing ocean ecosystems sustainably Using fishing equipment which doesn’t damage delicate habitats such as coral reefs Reduce overfishing – allow fish stocks to recover and harvest them at a rate which won’t destroy them for future generations Use appropriate sized nets – not too small that too many young fish are caught, but not too big that catches are unsustainable Allow poorer people to carry out subsistence fishing Involve local people in decision making – participatory planning Do not restrict the ability for local people to carry out their livelihoods and harm income

10 Named example of local marine management: St Lucia THREATS: Volcanic island Narrow continental shelf Increased tourism Deforestation High poverty CONFLICTS ARISE BETWEEN: Local fishermen Tourists Yacht owners Divers Hotel owners Government Conservationists SO HOW ARE THE THERATS AND CONFLICTS BEING MANAGED? The SMMA ‘Zoning’ of areas of coast around the town of soufriere (fishing areas, yach tmooring areas, conservation areas, dive sites etc.) Participatory planning – local people are involved in decisions SMMA PROBLEMS: Cost Rangers had to be supplied with equipment, which costs money Has led to increased tourism Some conflicts still remain, e,g, between fishermen and divers.

11 Named example of regional marine management: North Sea fishing quotas Currently, the EU have implemented the ‘Common Fisheries Policy’ which sets quotas to fishing fleets around the North sea in terms of how many fish they can catch in a year. If they exceed these quotas, they must pay a fine. The same rules apply to the size of the fleet in each area. Limits are set on the number and size of fishing boats that can be sent out. Fish stocks, particularly cod, have been in decline in and around the North Sea for the last 30-40 years. PROBLEMS: Fishermen have to be compensated for the loss of earnings. This is expensive Any extra fish caught over a quota are dumped back into the sea, dead.

12 Named examples of global marine management MARINE PROTECTION AREAS Aim to limit damage to coral reefs Incentives to reduce pollution Limit amount of fish caught Limit amount of divers using reefs Educate people on conservation HOWEVER, many reserves are poorly managed or have little policing due to their size. THE LAW OF THE SEA Covers a wide range of issues including pollution, fishing, navigation, scientific research, use of continental shelves. Addresses all types of ocean pollution, both ocean and land-based Each country regulates and polices the waters surrounding its coast HOWEVER: New technologies are allowing even deeper ocean exploration and exploitation Increasingly complex pollutants are entering the oceans from new industrial processes MARPOL: Rules for design of ships, and to regulate dumping of waste from ships at sea, which has reduced oil spilled into oceans by 80%

13 Past Questions 1. Outline the characteristics of food webs (2 marks) 2. Using named examples explain how marine food webs can be disrupted by human actions (6 marks) 3. Explain how bleaching may lead to a decline in marine species (2 marks) 4. Suggest one reason why tourist development on the coast often leads to the clearance of mangrove swamps. (1 mark) 5. Define the term ‘overfishing’ (2 marks) 6. Outline the process of Eutrophication (2 marks) 7. Suggest how marine ecosystems (such as coral reefs) bring benefits to local people. (2 marks) 8. Describe one benefit that marine eco-systems (such as coral reefs) bring to local people. (2 marks) 9. Using names examples, explain how humans can have both positive and negative impacts on marine ecosystems (8 marks) 10. Explain how climate change is adding stress to marine ecosystems. (6 marks) 11. For a named marine ecosystem, examine why it is under increasing pressure (8 marks) 12. For a named marine ecosystem describe one way it has been damaged (2 marks) 13. Suggest two reasons why many fish stocks have fallen. (2 marks) 14. Using named examples, explain why marine ecosystems (such as coral reefs) are increasingly under threat. (6 marks) 15. Describe how marine eco-systems (such as coral reefs) are being damaged. (6 marks) 16. Using named examples, explain how marine eco-systems can be managed (6 marks) 17. Using examples, describe how marine ecosystems can be managed sustainably.(6 marks) 18. Outline one aim of sustainable management of marine eco-systems (2 marks) 19. Using examples, explain how global actions are attempting to create sustainable marine ecosystems. (6 marks) 20. Identify a global action taken to help maintain ocean health. (1 mark) 21. For a named marine ecosystem, explain why people may disagree about its 22. management. (6 marks)

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