back to index ofchapters1. How has the United Nations defined the world 'pollution'?
Ans. The introduction of harmful waste substances into a natural areais termed pollution. The United Nations Organisation has defined pollutionof the marine environment as the introduction by humans, directly or indirectly,of substances or energy into the marine environment resulting in such deleteriouseffects as harm to living resources, hazards to human health, hindranceto marine activities including fishing, impairment of the quality of seawater and reduction of amenities.
2. How would you live if you were really concerned about pollution?
Ans. If we were really concerned about pollution, we would grow our ownvegetables and food supply and live very modestly with no dishwashers, garbagedisposal unit or air conditioners.
3. How many tonnes of metal, plastics, paper and glass does a developedcountry throw away each year?
Ans. The amount of garbage that a developed country throws out each yearhas been estimated to contain:
· 400 000 t of metal;
· 600 000 t of plastics;
· 1 000 000 t of paper (which represents 10 million trees or alarge forest); and
· 700 000 t of glass, mostly in the form of soft drink and beerbottles.
4. How do plastic bags affect turtles?
Ans. Seals and turtles eat plastic bags in mistake for jellyfish (Figure231.1). They choke on the plastic bags and eventually die. An autopsy ona sperm whale once revealed more than 40 plastic bags stuck in its throat.
5. How can fishing nets kill seals?
Ans. By wrapping around their necks and choking them.
6. How are birds affected by fishing lines?
Ans. When they build their nests the line gets entangled.
7. Explain why the dumping of radioactive wastes in steel drums is apoor waste disposal practice.
Ans. Radioactive waste, probably the worst polluting substance ever,is dumped in many parts of the Pacific Ocean. Despite being the most dangeroussubstance ever to be created, it is packed into drums and dumped into thesea. The drums, which can contain highly radioactive plutonium, will eventuallycorrode in the sea water allowing these substances to escape. Radioactivitywill then enter food chains and eventually human bodies.
8. How do people's attitudes affect the amount of litter dumped?
Ans. Peoples attitudes therefore determine how much waste is createdeither by deliberate or ill-informed means. An examples of deliberate litteringwould be throwing rubbish out of a car window. An example of ill-informedlittering could be leaving your rubbish at the beach in a bin that birdscould get at.
9. What is the difference between point source and non-point source pollution?Give two examples of each.
Ans. Point source pollution is where the pollution comes from a specificpoint, for example hot water from a powerhouse (Figure 233.1), paint stripperfrom a smash repair shop (Figure 233.2), oil from pumps (Figure 233..3)or sewage from a wastewater treatment plant (Figure 233..4).
10. What is the name given to oil when it spreads over the ocean?
Ans. When oil spills, it spreads over the ocean's surface forming a thinlayer called a slick.
11. How does oil pollution affect birds?
Ans. Animals that live on the surface, such as birds and seals, becomecoated with oil and die. Oil covers seabirds when they land on the surfaceand their feathers lose their waterproofing capacities. When the birds tryto preen their feathers (see Chapter 26), they ingest the oil and die. Theyalso die as a result of hypothermia (loss of body heat) because the insulatingair layer around the body is lost when the oil slicks the feathers flat.
12. What are the dangers involved in discharging untreated sewage intothe sea?
Ans. Sewage treatment can involve up to three levels of treatment: primary,secondary and tertiary. Primary treatment of sewage involves a settlingand chlorination process which is very inefficient in reducing bacterialpollution of our seas because it does not remove all solid and nutrientwaste.
Figure 229.1 on Page 229 shows a sewage treatment plant that dischargesprimary-treated sewage directly into the sea. Obviously, nearby beacheswill be affected by bacterial and other untreated wastes from the seweragesystem .
13. Name one source of thermal pollution and describe how an increasein water temperature affects the animals living in the water.
Ans. Many industries use heavy machinery which generates large amountsof heat. Industries such as steel manufacturing and electricity generationuse large volumes of water as coolant. This use raises the temperature ofstreams and rivers involved by up to 10oC causing thermal pollution. This,of course, will have a major effect on natural communities and individualorganisms living in these areas. The behaviour patterns of many aquaticanimals are influenced by water temperature, for example, temperature isstimulates many fish to spawn and migrate. Many fish are limited to waterof a specific temperature and thermal pollution can influence migrationpatterns in rivers.
14. How does mercury affect humans?
Ans. Mercury poisoning of humans was first noted in the 1950's at MinamataBay, Japan, where mercury was polluting the water and contaminating seafood.The fishermen of the bay and their families suffered damage to their nervoussystems and over 110 people died as a direct result of mercury poisoning.Many others were left crippled, blind and/or infertile.
15. Define the term 'catchment'.
Ans. A catchment is a term which describes the area of land which contributesrunoff to a particular creek, river, lake or the ocean. Figure 235.1 isa schematic diagram of a catchment with a river and a number of creeks.
16. Define the term 'toxic compound'.
Ans. A toxic compound is a substance that can kill, injure or impairthe functioning of an animal by its chemical action. These compounds arealso dangerous to humans and must be handled with care.
17. Name two other toxic compounds produced by manufacturing industries.
Ans. Many other toxic compounds are produced by manufacturing industriesand most cannot be disposed of safely. Thousands of tonnes of lead and otherheavy metals are released into the air simply by industries burning fossilfuels which contain these elements. Industry also releases into our waterwayschemical substances such as acids, detergents, plastics, and solvents thatare hazardous to marine life.
18. What is the difference between the stormwater system and the seweragesystem?
Ans. Stormwater pipes are big pipes designed to carry a lot of waterin a very quick time to prevent flooding. Sewerage pipes, as shown in Figure236.1, are much smaller because they are designed to carry a limited amountof wastewater from your sink, toilet and bathroom.
19. Why does connection of the stormwater system to the sewerage systemcause bacterial pollution of our seas?
Ans. If stormwater pipes are illegally connected to the sewage system,heavy rain will overload the system and wastewater will flow up out of inspectionholes, into the street and into the sea polluting our beaches and creekswith bacteria (Figure 236.2).
20. Name five impacts of polluted stormwater on a local community.
Ans.
· loss of aquatic life caused by poor water quality;
· weed infestations caused by garden refuse dumped in creeks;
· silted-up waterways caused by runoff from bare earth
· lower property values caused by degraded views; and
· higher local authority rates caused by increased maintenanceof waterways and public parks.
21. What are the two groups of insecticides harmful to marine life?
Ans.
· the chlorinated hydrocarbons or organochlorines such as DDTand Dieldrin; and
· the organophosphates.
22. List the four sources of oil pollution. Which of these sources causesthe most pollution of the ocean?
Oil pollution poses a major threat to the marine environment. The sourcesof this pollution are industry, spillages from oil rigs and oil refineries,discharges from ships and tanker accidents. (Oil from roadways is a non-pointsource of pollution, which is discussed later in this chapter). Industryis the major source of oil pollution. Oil spillages from tankers only represent4 per cent of the total oil pollution of the oceans.
23. Explain how oil pollution affects the life in the oceans.
Ans. One litre of oil can form an oil slick covering 8000 m2. This hasa catastrophic effect on any coastline the slick contacts. The oil smotherscoral reefs and mangroves. Shellfish, such as oysters and mussels, becomeinedible and whole fisheries may be wiped out. Birds have already been discussedin question 11.
24. Give an example of how one generation had to pay millions of dollarsrepairing the coastal zone.
Ans. The cost of repairing and replacing beaches after people cut downtrees to 'improve' their view and allowed sand to blow away on the QueenslandGold Coast was estimated in 1997 to be over $100 million. This cost hasbeen paid by one generation who had nothing to do with the environmentaldestruction of sand dunes in the 1950's
25. Give an example of how an environmentalist might suggest to industrya inexpensive way to store chemicals so that they do not leak into the stormwatersystem.
Ans. Environmentalists must come up with new ways to operate and manufactureproducts. The changes can be as inexpensive as building a concrete dam wallaround drums of oil stored on a factory floor to contain any oil that leaked.
26. Give one example of how the disposal of wastes at sea may be beneficialto marine life.
Ans. Disposal of wastes into the sea may, in some cases, be beneficial.Artificial reef structures have been made out of old car bodies, barges,old ships and other structural materials. These artificial reefs providea habitat for marine life which flourishes with this protection. Once anartificial reef structure has been formed, reef building organisms becomeestablished in the area and start to build a natural reef. Many artificialreefs have been set up around the world.
27. What happens to sand when the coastal vegetation is destroyed bycoastal developments?
Ans. Many housing developments have been built too close to the coastalzone leading to the complete destruction of coastal vegetation. When thisoccurs the sand on the beach just blows away leaving erosion scarps as shownin Figure 240.1.
28. What is meant by a 'throw -a-way society'?
Ans. Unfortunately, we are now living in a 'throw-away' society. Mostof the goods we buy have specialised packaging which cannot be re-used.Many items we buy are used once and then disposed of, such as disposablenappies and paper tissues. Manufacturers are now even making disposablecameras and disposable contact lenses. Many manufacturers are only interestedin making cheap goods which have a short life. Other manufacturers are runningadvertising campaigns telling us our old models are inadequate or obsoleteand that we need to purchase their new improved model. But what are we goingto do with our old model?
1. Research your own contribution to pollution by finding out the answersto the following questions.
a. How heavy is your school bag and what weight of paper do you estimateis in it? How much paper would you estimate you would use in one year?
b. What materials were used to make your school pens? How many syntheticitems, e.g. plastics, are found in your bag?
c. Work out the volume of wood in the classroom furniture and fittings.What other types of products have been used in the construction of the schoolbuilding? How could the design of this building be improved to make it moreenergy efficient?
Suggestions.
Use a set of scales and take the time to sort out the materials in yourbag and shopping.
2. Estimate the volume of rubbish produced by your street during theyear.
Suggestions.
Do a survey with your neighbours and multiply buy the number of housein your street. Draw up a materials analysis sheet. Use your class discussiongroup to brainstorm ideas.
3. Some material are said to be biodegradable. What does the term 'biodegradable'mean?
Suggestions.
Use dictionary, chapter glossary.
4. What type of packaging is found on items bought from the local supermarketin your last shopping trip? How could the amount of packaging be reduced?
Suggestions.
Use own research and notes
5. Use the library to research other sources of pollution. These include:
a. anti-fouling paint
b. contraceptives
c. natural pollution from volcanoes
d. acid rain
e. dredging
f. mining
Suggestions:
Use library, local chemist, council environmental officer, parents assource agents. Read labels and packaging information.
6. Use your library to gather information on the major oil spills thathave occurred in the Pacific Ocean in the last 10 years. Record detailsof these spills and the methods used to contain break-up the oil spill.
Suggestions.
Australian Marine Safety Authority Oil Pollution kit.
Planning for the inevitable.
PO Box 1108 Belconnen ACT 2616. Kit contains National Plan for oil pollution,video, fix-a-slick game for IBM's.
7. Are there any factories or heavy industry in your local area? If so,where are they located? How might water be used in these industries andwhat happens to the water after use?
Suggestions:
See your local WaterWatch group, environment group.
8. Discuss ways in which you could reduce pollution when you go boating.
Suggestions:
Read pamphlets on stow it don't throw it. Ask you boating patrol officers.
9. Research possible causes of fish kills.
Suggestions:
Ask your local fisheries officers, local authority environmental protectionofficers.
10. Are there any artificial reefs in your local area? If so, when werethey established and who was responsible for organising the construction?Are they successful in your area?
Suggestions:
Western Australia is set to get a surfing reef but many fishing reefshave been used for years. Ask locals.
11. Make a list of eight disposable items you can buy from your localsupermarket.
Suggestions:
Use local supermarket research.
12. Explain why landlocked seas and lakes are so likely to be affectedby pollution.
Suggestions:
Use library research. The section on the Mediterranean Sea in this chaptergives some clues.
13. Where does most of the pollution occur in our country?
Suggestions:
Ask your local environment group.
14. Find out how sewage may solve some of the fuel problems of the 20thcentury.
Suggestions:
Ask your State or Regional environment council. Ask local environmentalistsabout use of reclaimed water.
15. Organise a trip to a local beach to survey the amount and types ofpollutants found on the beach.
Suggestions:
Go on the trip. Find out about adopt-a-beach.