Sea near HK : Nan Hei

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1 S.3 Geography - Ocean in troubles Why are ocean important to us (1). A container terminal - Transport land use(cheap transportation) (2). A beach - Recreation (3). A fish culture zone - Food supply (4). A Chinese white dolphin - Habitat for marine life (5). A night view from Victoria Harbour - Tourist attraction A. Pacific Ocean - Largest ocean in the world. B. North Sea - Produces plenty of petroleum and fish for European countries. C. Atlantic Ocean - Columbus had traveled across and discovered the new continent. D. Nan Hei - Most HK marine fisherman earn their living. E. India Ocean - Lies between Africa and Australia. F. Caribbean Sea - Many Americans like to enjoy tropical cruise vacation. G. Arctic Ocean - Large areas of ocean are frozen. H. Mediterranean - It separates Italy from Egypt. Sea and ocean account for 71% of the total area of the earth s surface. Four largest ocean : Pacific Ocean, Atlantic Ocean, Indian Ocean, Arctic Ocean. Sea : Area of water near the land. Ocean : The outer part of the sea. Area : Ocean > Sea. Sea near HK : Nan Hei 1

2 X : Major fishing ground Located on the contient shelves (It deep 180m) Why X has lots of marine animals and fish? Since water is not deep. Sunlight can pass through easily. Rivers, tides and ocean current can also bring rich supplies of nutrients. Energy and minerals we can get from the ocean Minerals :Salt, tin, gold, diamonds. (Minerals are important for industrial development) Fossil fuels beneath the sea bed : Oil, gas and coal Renewable energy can be developed along the shore: Tidal power Other activities in the oceans and along the coastal areas : (1). Trade and shipping Advantage of sea transport : The cheapest transportation over long distance (Over 70% of world trade depends on shipping. Goods can be sent in large quantities over a long distance at the lower cost.) (2). Recreation and tourism Example in the coastal regions: Enjoy diving, dolphin-watching trips (Beautiful scenery along the seaside also promotes tourism.) How ocean affect our climate? The SE side of HK (e.g. Sai Kung), receive higher annual rainfall. The NW side of HK (e.g. Yuen Long), receive lower annual rainfall. Why is the distribution like this? The SE onshore wind brings higher rainfall to the eastern part of HK in summer. Relief rain fall on the windward sides of the hills (e.g. Tai Mo Shan). The NW part like Yuen Long is under rain shadow effect. 2

3 Inland location Coastal location Temperature in summer Higher Lower Temperature in winter Lower Higher Annual range of temperature Larger Smaller Types of climate Continental climate Maritime Climate Why is temperature differen between inland location and coastal location in summer and winter? Sea heat slowly in summer and cools slowly in winter. The annual range of temperature is smaller. Coastal location have mild climate. It is called maritime climate. It favours people to live. Warm and cold current Ocean current : large-scale movement of surface water in the ocean. How do they affect temperature? 1. Warm current (e.g. North Atlantic Drift) : Move from the tropics to the poles Increase the temperature of areas the flow by (Places affected by warm current are suitable for people to settle) 2. Cold current (e.g. Peruvian current) : Move from poles to tropics Lower the temperature of area the flow by Advantages of living in coastal area : Can get food by fishing. Can get energy and minerals from the ocean for the industrial use. Can be use as highway for trading and transport. Have beautiful scenery. Have good recreational grounds. Have mild climate (which is suitable for people to settle). The marine ecosystem (self-supporting system) Producers (Algae, seaweed) Primary consumers (Jelly fish, krill) Secondary consumers (Squid, Shark Tuna) Over-fishing Method of fishermen usually use to catch valuable coral fish : Trawling Other two methods: Blast fishing, poison fishing. Why the above methods destructive to marine life? 1. Destroy the food chain. 2. Destroy the coral habitat. 3. It will kill the young fish. 4. The poison accumulation may harm the endangered sehta animals. 3

4 Endangered of fish: Since there is over-fishing, food chain will be damager. So that some fish will die because of shortage of food. The marine ecosystem is upset. What can we do to reduce the impact of over-fishing : 1. Set up the limit of the amount of fish catches each year 2. Restrict the size of fish can be caught 3. Fish band period 4. Limited the number of fish vessels 5. Regulate mesh size 6. Fish farming Disadvantages and difficulties Regulate mesh size : Fish are caught until they grow up and have time to reproduce Fish ban period : Since there is no supply of fresh fish, therefore the price of fish is higher. Costly to control the size of fish caught : It needs a lot of labours and time to sort fish. Difficult to limiting the number of fishing vessels : It is likely for some people to go fishing without a proper license. It is also difficult to patrol in the sea. Fishing band Period Advantages: 1. It protects the marine ecosystem and the food chain. 2. There is time for reproduction. 3. This can increase the number of fish species. Disadvantages: 1. There is no supply of fish in fish ban period and the price of fish will increase. 2. Fishermen also have low income during this period. The Sea or sewage Water quality: Water around HK is blue but water around Macau is brown in colour. Reason : Zhujiang brings sediments to the marine water of Macau. Dredging and reclation take place along coastal areas of Macau. 4

5 Source of water pollutions : 1. Oil pollution - Oil spillage from the oil tanker Effects of oil spillage: Fish will die The oil prevents the oxygen from dissolving in the water. Animals and plants under the sea will be short of oxygen. 2. Toxic materials Industries 1. Toxic materials are passed from one marine animal to another through the food chain. 2. People will be poisoned if they rat the polluted seafood. 3. Solid Waste Sources: Domestic Impact: 1. Solid waste may choke the marine animals. 4. Organic Waste Domestic 1. It led to the grow of algae (red tide). Decomposition of dead algae use up much of oxygen. Marine animals and fish will be killed. 5. Sediment Sources: Reclamation Impact: 1. Dredging the sea bed and dumping of sand/mud increase the turbidity of the sea water. 6. Radioactive materials Nuclear Plant 1. Dumping of radioactive waste into the sea destroy the marine life. 7. Pesticides / Fertilizers / Animal waste Farming 1. Fertilizers and animals waste may lead to the grow of algae when washed into the sea. 2. Pesticides cause water pollution. Is reclamation good or bed? People opposed the reclamation project:environmentalist, boatmen, some HK citizens, tourists People support the reclamation project:government, developers, some HK citizens, workers, tourists 5

6 Viewpoints of the supporters: 1. More job opportunities 2. Water front promenade attracts tourists 3. Developers earn more money by construction commercial buildings 4. Solve traffic congestion 5. More recreational land use for local people Viewpoints of the opposing groups: 1. The marine life habitats are destroyed. Dredging and dumping of sand/mud increase turbidity and cause pollution. 2. The beautiful sea view is destroyed. 3. Water pollution is serious and it generates bad smell because the flushing effect is weaker. 4. Wave becomes swifter. Sea traffic accident may occur. What can we do? (1). Government had set up marine parks and reserves Marine Parks are used for conservation and education people. We can t go jet-skilling and water skilling in marine parks because it will damage marine eco-system. 1. Yan Chau Tong Marine Park ( 印洲塘海岸公園 ) 2. Hoi Ha Wan Marine Park ( 海下灣海岸公園 ) 3. Sha Chau and Lung Kwu Marine Park ( 沙洲及龍鼓灘海岸公園 ) 4. Tung Ping Chau Marine Park ( 東平洲海岸公園 ) 5. Cape D'Aguilar Marine Reserve ( 鶴咀海岸保護區 ) (2). Sewage treatment Harbour Area Treatment Scheme - It is an overall sewage collection, treatment and disposal strategy for areas on both sides of Victoria Harbour. (3). International cooperation - Many governments are co-operating to save the oceans. For example, the law of sea was passed in the United Nations Convention in (4). Environmental awareness 6

7 - Rise the environmental awareness of the public by education. We can do to protect our ocean: 1. Don t throw rubbish into the sea. 2. Save resources, food and water. 3. Use less detergent. Don t damage the coral reef. 7