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Unit 5 The ocean resources
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How important are the oceans as a source of food?
Unit 5 The ocean resources How important are the oceans as a source of food? The marine ecosystem -- Oceans are rich in marine life with different living things range in size. Phytoplankton (Tiny plants) Zooplankton (small fish and animals) Food Food Food Larger marine creatures Fish and marine animals Food All of them become part of the food web in the ocean.
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Unit 5 The ocean resources
Food web in the ocean Phytoplankton Zooplankton Sunlight Less Sunlight No Sunlight Fish Seaweed Shark Dolphin Baleen whale Squid Sperm whale Octopus Sediments from land Crab 1 000 m 200 m 5 000 m Shell fish Anglerfish Eel
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How important are the oceans as a source of food?
Unit 5 The ocean resources How important are the oceans as a source of food? Fish as a source of food The world’s catch of ocean fish is about 100 million tonnes a year. The most productive regions are the temperate and sub-tropical continental shelves of the northern hemisphere.
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How important are the oceans as a source of food?
Unit 5 The ocean resources How important are the oceans as a source of food? Fish as a source of food Less valuable fish caught are turned into animal feed and fertilizer. Seaweeds are obtained from the sea. They are used as food for humans and animals or made into fertilizer.
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The world’s important fishing ground
Unit 5 The ocean resources The world’s important fishing ground Arctic Ocean Pacific Ocean Indian Ocean Atlantic Ocean Fishing grounds Asia Australasia Africa North America South America km ° N ° S Europe N
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How important are the oceans as a source of food?
Unit 5 The ocean resources How important are the oceans as a source of food? Fishing industry in HK Most of the marine fish caught are from the shallow continental shelf of the South China Sea.
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How important are the oceans as a source of food?
Unit 5 The ocean resources How important are the oceans as a source of food? Fish caught by local fishing fleet Fish imported Thousand Tonnes Fish Year Fish consumed in Hong Kong Recently, the catch by local fishing fleet has declined. Over-fishing and the pollution of the seas around Hong Kong are the reasons.
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Are oceans rich in mineral resources?
Unit 5 The ocean resources Are oceans rich in mineral resources? Storehouse of minerals Mixed with coastal sand and gravel are ores containing tin, gold, platinum, diamond and other gemstones eroded from land. Mining vessel Gold mining Diamond mining
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Are oceans rich in mineral resources?
Unit 5 The ocean resources Are oceans rich in mineral resources? Storehouse of minerals From oceans we can extract a great variety of elements such as magnesium, bromine and copper. Copper Basin Copper
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Are oceans rich in mineral resources?
Unit 5 The ocean resources Storehouse of minerals The sand and gravel in the sea are very useful building materials. Salt that we all take each day comes from the sea. Sand Lake Salt Sand
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Are oceans rich in mineral resources?
Unit 5 The ocean resources Are oceans rich in mineral resources? A source of fresh water In arid regions , desalination plants are built along the coast to purify sea water.
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Are oceans rich in mineral resources?
Unit 5 The ocean resources Are oceans rich in mineral resources? A source of fresh water The fresh water produced is used for drinking, irrigation and industry. Desalination plants
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Can we obtain energy from our oceans?
Unit 5 The ocean resources Can we obtain energy from our oceans? Beneath the sea lie rich oil and gas. Modern technology has made off-shore drilling of oil and gas possible. Example: the South China Sea are regions rich in oil and gas.
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Distribution of off-shore oil basins
Unit 5 The ocean resources Distribution of off-shore oil basins km Off-shore oil °N ° N ° S N Asia Europe Africa North America South America Australasia Arctic Ocean Pacific Ocean Indian Ocean Atlantic Ocean
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Can we obtain energy from our oceans?
Unit 5 The ocean resources Can we obtain energy from our oceans? Coal There are layers of coal lying beneath the sea. They are coal seams which extend from land outwards to the continental shelf.
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Can we obtain energy from our oceans?
Unit 5 The ocean resources Can we obtain energy from our oceans? Coals are hydrocarbon compounds which give out a large amount of heat when burned, which is good for generation of electricity. Transporting coal Coal mining
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Can we obtain energy from our oceans?
Unit 5 The ocean resources Can we obtain energy from our oceans? Tidal power It is now possible to harness tides and waves for the generation of electricity. They are renewable energy which are inexhaustible and do not pollute the environment. Tides and waves are our future source of energy.
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Case: The River Rance Tidal Power Scheme
Unit 5 The ocean resources Case: The River Rance Tidal Power Scheme English Channel France Britain N Location of the scheme: At the estuary of River Rance in Brittany, northwest of France. River flows into the English Channel. Difference between high and low tides: 8.5 m
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Case: The River Rance Tidal Power Scheme
Unit 5 The ocean resources Case: The River Rance Tidal Power Scheme Dam Turbine Estuary Tide rising (section) Tide falling (section) How tidal power is harnessed to generate electricity Sea water is trapped behind the dam to form a reservoir. As the tide rises water from the sea flows through this dam which drives the turbines to produce electricity. When the tide ebbs, the trapped water is released and flows through the dam back to the sea.
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Case: The River Rance Tidal Power Scheme
Unit 5 The ocean resources Case: The River Rance Tidal Power Scheme Advantages : It does not pollute the environment. It is clean and inexhaustible. Capacity of power plant: kw Year Built : 1967
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Can we obtain energy from our oceans?
Unit 5 The ocean resources Can we obtain energy from our oceans? Marine disputes As oceans are rich in food and mineral resources, disputes over fishing rights, mining rights, continental shelf boundaries, islands and reefs regularly occur among coastal countries. For example: Diao-Yu-Tai, which belongs to China is claimed by Japan.
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Unit 5 The ocean resources
Terms to learn Phytoplankton (浮游植物) -- very tiny plants that drift or float in the ocean. Zooplankton (浮游動物) -- very tiny animals that drift or float in the ocean. Coal seam (煤層) -- layers of coal. Fossil fuels (化石燃料) -- these are the remains of organic materials in rocks and are made up of hydrocarbon compounds. Oil and coal are examples of fossil fuels.
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