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Environmental Management Hydrosphere unit 2.7-2.10

Environmental management pg 100-115

Tan Wei Qin

on 30 May 2012

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Transcript of Environmental Management Hydrosphere unit 2.7-2.10

World Ocean Fisheries The Importance Major fishing areas Fishing Grounds Overfishing FOOD ! JOBS ! Fish is a major source of food! source of protein for
developing countries :)
Like us MALAYSIANS Both full time and part time
depends on FISHING There's also : Canning Curing Freezing Building boats Making nets Fishing tackle Ice production Islands because
they're surrounded by WATER ! Asia cause that's where
developing countries are :) There's 4 great fishing grounds : North west Pacific-seas

Northwest Atlantic

Northeast Atlantic

Northeast Pacific from Alaska to California ? Noticed something? They're all NORTH ! Let's sail to fishing grounds
to find out why :) Fishing grounds are located
predominantly in the northern hemisphere
because of NATURAL FACTORS. naturally rich in plankton because of shallow waters. BUT Mineral transporting currents
(Labrador, North Alantic Drift,
Kurile) does not function effectively. Because Thermo- layer occurs because
the warm surface and cold surface waters does not mix that much. And shoal fishes like mackeral, cod and haddock prefers cooler waters. Thermo layer : The heat layer in the atmosphere
or water, at a different temperature than the on above or below. Groups There's groups for fishes :) Pelagic : Lives near the ocean surface
Like : mackeral, herring, sardine Demersal : Lives closer to the floor of the ocean
Like : cod, plaice, haddock, sole Crustacea : crabs, lobster, crayfish Mollusses : oyster, mussels, cockles Others : whales, seals, turtles, dolphins : deplete the stock of fish by fishing insufficient fish to carry on the reproductive cycle and commercial fishing stops Causes Technology Sonar to identify species Radar to locate fish Bigger Boats Larger nets but small holes So immature fishes get caught too and then thrown away Refer to handouts pg 103 table 2.8
for changes Consequences :( if people keeps on fishing non stop, it'll take years to replenish so Less fish Jobs lost Strategies :) hooray coastal countries has established zones of 200 nautical miles around their shore. So that particular country has rights to all natural resources in that 200 nautical miles. The zone is known as Economic Exclusion Zon (EEZ) How countries manage their EEZ ? QUOTAS ! Annual limits are set for the amount and types of fish that can be caught SUPPORTED BY Management Policies Such As Closed season during main breeding time
Restricted areas
Limits on net types and sizes Not all fishermen follow the quotas. :( They : catch more than allowed by the quota
using nets with small holes
fishing in restricted areas When small fishes which are not allowed to be caught are caught the fisherman normally throws it back into the sea DEAD. 25% of the world fish catch consist of rejected fishes (by-catch) Marine Pollution Impact Control and Remedies Areas at most risk There's pollution in open oceans
costal regions are polluted even more. BECAUSE 75% of marine pollution comes
from LAND. 25% comes from ship's dumpings, offshore mining and oil production. refer to table 2.9 pg106
for types of waste and source and impacts So of the pollutions are immediate and easy to observe
others are longer lasting and they're more deadly Oil spills effects the marine life throughout the affect areas. Radioactive isotopes can cause cancer for humans,
metals accumulated in living organisms gradually becomes more concentrated as they are passed on my food chain. It will affect sea birds and marine animals The consequences will last longer in cold environments
where the ecological recovery is slow. Exxon Valdez in Prince William Sounds, Alaska spilled a relatively small amount of oil into one of the riches fishing areas in the world.
But 15 years later it has not made a full recovery. Refer to figure 2.56 for major oil spills. Areas at most risk would be an area where wave actions are weak and where water flow is restricted. So therefor pollutants are more concentrated. Such as sheltered bays and estuaries where wave actions are weak and narrow or enclosed seas and gulfs for water flow restriction. Oil producing regions such as the Arabian Gulf is also at high risk, because of it's rigs and tanker terminals. it's a global problem all countries contributes to it because all oceans are linked and ocean currents transfer water . As you know that all countries are resposible. So
the United Nations (UN) must take the lead role. To acheive cooperation between governments. The United Nations Environment Programme (UNEP), tackles pollution in particular areas where countries are involved like the shores of the Black Sea. The Black Sea only has one narrow connection to the Mediterranean Sea and two of Europes river's, Danube and Dneiper flows into it. The rivers carries pollutants from 9 different countries. The Black Sea has already suffered alot of ecological damage from nutrients and toxic chemicals. And eutrophication is taking place. Dealing with oil spills Step 1
You wouldn't want the oil spill to spread so they use booms which are inflatable tubes to stop it from spreading Step 2
Next they break up the oil into droplets, making big spills small spills by detergent spraying. The chemicals breaks up the oil. Step 3
some of the remaining oip can be removed by skimmer. Which is oil drawn up by absorbent belt and into a collecting tank. Prevention Prevention is better than a cure. So the way to prevent oil spills is to. Have a double hull for the tankers. Most of the tankers only have 1 hull. If the hull hit a rock or a ship the oil will spill out but if there's 2 hulls then it won't because the first one woud most likely be damage. So the USA and EU are insisting that all tankers will have a double hull by 2015. refer to figure 2.58 pg109 for the cleaning operation The Southern Ocean Rich in Life The Food Chain Human use of resources Past Present Future The Southern Ocean consist of the southern parts of the Alantic, Indian, Pacific Oceans where they are border Antartic. So it's cold that's why it's rich in life. Cold water is better than warm water when it comes to holding dissolved gasses such as CO2 and oxygen. Nutrients and minerals are kept in suspension so the phytoplankton can use it, because of the strong currents and storms. So this prevents thermo-layers forming. The long hours of daylight during summer alows photosynthesis to take place more often , which allows having a lot of phytoplankton So basically southern oceans are rich in life because there is a lot of phytoplankton and there are more nutrients, and gasses. The phytoplankton is the basis of the food chain. The zooplankton in the southern ocean is shrimp like krill. Which eats the phytoplankton. Phytoplankton is plankton consisting of small microscopic plant and zooplankton is plankton consisting of small animals and the immature stages of larger animals. Krills often form a dense swarm just below the surface, so the ocean would sometimes look pink! This mean the predators can catch them easily. Krills are th major link in the Southern Ocean and the Antartic Ocean. refer to figure 2.61 for the food chain in the Southern Ocean. Deffinition There has been 200 years of resource exploitation in the Southern Ocean. 1800 to 1840 th main catch was seal. After 1840 they stop catching seals and started catching whales, because the seal population had virtually wiped out. The caught whales for their oil. 100 years later the whale population was a tiny percentage of what they had 100 years ago. The International Whaling Convention was set up in 1946 and there was controls on how much whales should be caught but by 1954 the last whaling sttation was abandoned. It was abandoned because whaling stocks had become so low that they could not gain profit. The main target today is fish. In the 1970s the main catch was rock cod now catches are low. So basically large catches in the early years make fishes dissapear! Not dissapear but it makes them scare. Russia and Japan fish to much commercial fishes so the were forced to fish something else. So they started fishing krill. In Russia krill is used for animal feed, mixing for other meats in sausages and fish balls. In Japan it is sold as flavouring for soup and pastes. Fishing is regulated in Southern Ocean by CCAMLR ( Convention on the Conservation of Antartic Marine Living Resources), set up in 1982 but ovefishing had already begun.So the north was overfished so the attraction went to south. Antartic fish tend to grow slower and it takes a long time to reach maturity for reproduction. The Antartic Treaty guarantees that the continent should be left open to all nations for scientific and PEACEFUL pusuits. So in the Environmental Protocol signed in 1991, no mineral activity is allowed and oil drilling on the continental shelf.The land and waters of the Antartic does not own to any country. Water problem ( Fresh Water Resources) Population growing so more contaminated water. Decreasing fresh water availability per person
1950-16000 meter cubic 2000- 7000 meter cubic More competition between users for demand of water on farms and in cities More and larger dams built. Longer transfer of water where it is needed. ( Ocean Resources) Rising demand for food and increasing amount of pollution Overfishing increasing, more damage to the marine ecosystem Fisheries collapsing, Increasing threats to natural system. Searching for new fishing grounds so contamination and overfishing is spread. Increasing amount of environmental damage and growing international conflict.
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