Topic 5 Pollution Management
Semester Exam Review Questions
Answers
Notes Ch. 5 – Part 1
5.1 – 5.2 Nature of Pollution. Detection pp. 217- 222
1. Is the spraying of pesticides on a field an example of point or non-point source pollution?
Explain your answer.
Non-point source as pollutant drains through soil into water
bodies [1]/mixes with other pollutants [1]; is untraceable to
a particular source [1]/blown by wind over large area [1].
Allow marks for a reasoned argument for a point source
e.g. a single nozzle spray and a contact pesticide [2]
2. State and explain which type of pollution, point source or non-point source, is
easier to identify, control and eliminate.
point source pollution is easier to control and eliminate than
non-point source pollution as the discharge can be treated or
diverted/dealt with at source
3. State one human activity that may cause eutrophication and is an example of a
point source of pollution.
a pipe discharging domestic waste water/sewage/detergents
(into the lake);
4. State one human activity that may cause eutrophication and is an example of
non-point source pollution.
run-off from farms/animal sewage/silage/fertilizers/run-off
and erosion from cultivation;
1
5. What is BOD? Biochemical oxygen demand. Basically the demand for
oxygen in a river by aerobic organisms
6. The BOD in a river at any point can be determined by what?
-
number of aerobic organisms at that point
their rate of respiration
7. Why do organic pollutants cause a high BOD?
Organic pollutants stimulates organisms that feed on the organic pollutant
to break it down. In doing this the organisms respire and use up a lot of
oxygen so the demand for oxygen ( BOD) is high. HIGH BOD =
ORGANIC POLLUTION.
8. Why is photosynthesis a problem when measuring BOD?
Because you only want to measure the demand of oxygen by aerobic
organisms. If you allow photosynthesis it will increases oxygen in water
and give artificially low BOD by raising the second measurement of DO 2
.So when you subtract ( DO1 – DO2) the over all BOD is artificially low.
9. List a 5 – step method to measure BOD:
5-step Method - BOD
1. Take a sample of water and measure volume.
2. Measure the oxygen level ( DO1) – should be HIGH
3. Place the sample in a dark place for 5 days ( lack of light prevents
photosynthesis which would release oxygen and give an artificially low
BOD)
4. After 5 days measure the DO2 again- should be LOW
5. The BOD is the difference between the DO ( DO1 – DO2) which shows
how much O2 was consumed by the organisms over the 5 days NOT
including O2 produced by photosynthesis.
6. HIGH BOD = HIGH ORGANIC POLLUTANTS = HIGH AMOUNT OF
AEROBIC ORGANISMS stimulated by organic pollutants.
2
10. By looking at fig. 5.2 which has a higher tolerance for organic pollution, Tubifex
or mayfly nymphs? Tubifex
11. Why is there less oxygen available in the water ( less DO) on warm days?
Higher temp. decreases DO in water – O2 tends to “evaporate” due to gaining more
kinetic energy from higher temp.
12. How do warm organic pollutants affect DO? Fish?
Decreases DO. Decreases fish since they need more O to respire.
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13. How and why does the population of Tubifex change close to the point
source pollution of the organic pollutant and further down stream?
Increases due to organic pollutant and feeds on the organic pollutant.
Then it is decreases going down stream as the organic pollutant becomes
less.
14. How and why does the population of mayfly nymphs change close to the
point source pollution of the organic pollutant and further downstream?
Decreases due to organic pollutant and increases down stream as organic
pollutant becomes less.
15. Make sure you understand fig. 5.3 p. 221
4
5
16. Outline one method of indirect measurement using a biotic index, that
would indicate that a lake is becoming eutrophic.



measure the abundance and diversity of species upstream/downstream
the abundance of low oxygen tolerant species (e.g. carp fish , Tubifex worms)
would increase
the abundance of high oxygen tolerant species (e.g. trout fish , may flies) would
decrease
5.3 Pollution Management, DDT pp 223-230
17. What is DDT , what was it used for during WWII and after WWII?
DDT – dichlorodiphenyltrichloroethane. Synthetic pesticide and persistant organic
pollutant (POP) that was used during WWII to control lice, typhus and malaria via
mosquitoes. Used after WWII as insecticide in farming.
18. Who is Rachel Carson, the name of her book and what did she claim?
An American biologist , whose book “ Silent Spring” ( 1962) claimed that
DDT was killing wildlife and could cause cancer in humans.
19. When was it banned? Several dates but by 1980
20. Explain bioaccumulation and biomagnification.
Bioaccumulation – retention and build up of non-biodegradable chemicals in the
body.
Biomagnification – concentration of a chemical increases at each trophic level. Top
predators may have concentrations of a chemical several million times higher than
the primary producer.
21. What is the WHO ? world health organization
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22. Fill in the blank:
Farmers exposed to DDT have higher risk of ___asthma and ____diabetes. DDT may
cause _liver __, _breast__ and __pancreatic__ cancer. In Ecuador the use of ____DDT___
___increased___ and there was a 61% reduction of _____malaria___.
23. If a lake is sprayed with a non-biodegradable insecticide to kill mosquitoes,
after a few years the highest concentrations of insecticide are most likely to
be found in the D
A.
upper layers of the lake.
B.
tissues of the mosquitoes and other insects.
C.
tissues of the freshwater plants.
D.
tissues of predatory fish and fish-eating birds.
7
24. The figure below shows a simple aquatic food chain which has been exposed to
a pesticide called DDT.
Land progressive sequence
Milk
Meat
Aquatic progressive sequence
Humans, the
ultimate accumulators
Third carnivore
(larger fsh)
Grazing
animals
Second carnivore
(larger fsh)
First carnivore
(larger fsh)
Herbivore
(smaller fsh)
Grass
DDT
spray
First accumulator
(algae, water plants)
Pollutant in
molecular form
[Source: Adapted from Goudie, A (1993) The Human Impact on the Natural Environment, Blackwell,
p.219]
(a)
(i)
State how many trophic levels are shown in the figure above.
(ii)
Identify which trophic level represents:
Ans : 6
the producers
the top carnivores
producers = first accumulator/algae, plants/level 1
top carnivores = ultimate accumulators/humans/level 6
(iii) State and explain what may be happening to the concentration of
pesticide in the food chain.
8
Bioaccumulation – retention and build up of non-biodegradable chemicals in the
body.
Biomagnification – concentration of a chemical increases at each trophic level. Top
predators may have concentrations of a chemical several million times higher than
the primary producer.
pesticide becomes increasingly concentrated as you go up
the food chain because each successive trophic level supports fewer
organisms and so the pesticide becomes concentrated in
the tissues
(b)
An estimated 1000 kg of plant plankton are needed to produce 100 kg
of animal plankton. The animal plankton is in turn consumed by 10 kg
of fish, the amount needed by a person to gain 1 kg of body mass.
(i)
Explain why the amount of biomass declines at each successive
trophic level.
10% of energy is used in respiratory processes at each trophic stage and
is lost as heat or waste
(ii)


Distinguish between a pyramid of biomass and a pyramid of
productivity.
pyramid of biomass represents biomass at a given time – SNAPSHOT
whereas pyramid of productivity represents rate at which
stocks are being generated over longer periods of time
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5.4 Eutrophication pp. 230 – 237
25. Outline one method of direct measurement that would indicate that a lake
is becoming eutrophic.






measure nitrate/phosphate/turbidity levels repeatedly over a period of time
measure turbidity by lowering a secchi disc into the water
nitrate levels increase as input of nutrients increases/phosphate
levels increase as input of nutrients increases/
turbidity increases as algae populations increase
measure amount of dissolved oxygen/BOD or similar;
26. Outline one method of indirect measurement using a biotic index, that would
indicate that a lake is becoming eutrophic.



measure the abundance and diversity of species upstream/downstream
the abundance of low oxygen tolerant species (e.g. carp fish , Tubifex worms)
would increase
the abundance of high oxygen tolerant species (e.g. trout fish , may flies) would
decrease
27. What are the there main ways of dealing with eutrophication?



changing human activities that produce pollution by using alternative
types of fertilizers
regulating and reducing pollutants – sewage treatment plants that
reduce nitrates
clean up restoration of lake by pumping mud out
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28. Changing human activities. Know these :
29. Regulating and reducing pollutants.
a) What does “ divert sewage effluent” mean?
To divert sewage from body of water
b) List 3 domestic campaigns used in Australia.
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30. Clean up strategies. List the main clean up methods.
31. Prevention of eutrophication at the source. List basic ideas.
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32. Describe and evaluate management strategies to restore a eutrophic lake.
Describe:




add aerators to the lake (to maintain survival of species)
remove aquatic plants during their growing period
dredge the mud from the bottom of the lake to remove nutrients
introduce species of fish which consume algae;
Evaluate:




aerators are expensive to operate
aerators do not reduce the pollution problem, so must be
used continuously;
aquatic plants which have been removed from the lake transfer
the nutrient overload to another ecosystem;
mud pumped from the lake transfers nutrient overload to
another ecosystem;
33. Development of a tourist resort near a lake is proposed. Outline strategies
for determining the environmental impact of the development on the
lake.




Environmental Impact Assessment/EIA/baseline study must
occur before any development begins
select biological (species diversity) biotic index to tes abundance of
species in relation to pollution. Tubifex worms, may flies, carp fish (
low DO) and trout fish ( high DO). Compare DO and BOD.
Select chemical (nutrient status) indicators to test : nitrates,
phosphates.
monitoring of the environment must continue at regular intervals
during and after development
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Notes Ch. 5 – Part 2
5.5 Solid Domestic Waste, Ozone pp. 238- 242
Know the following table
1. List 4 major types of solid household waste that is being recycled today by
most countries. Which item is worth the most money?
Material type
Examples
Organic material
garden waste, food/kitchen waste, wood
Paper
newspaper, writing paper, packaging,
cardboard, milk cartons
Plastics
soft drink bottles, plastic bags, plastic
containers
Glass
jars, bottles, plate glass
Metals
steel cans, aluminium packaging and
cans, copper pipes
Household hazardous
paint, dry cell batteries, car batteries,
fluorescent light bulbs
Miscellaneous
ceramics (bricks, tiles etc.) rock, ash, soil
2. What are the main categories in how household waste is being separated
– sorted at home?
See table above
3. What does the government do ( depending on the country) to motivate
and ensure that people are recycling waste?
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IB general comments about recycling :



incentives may be necessary to encourage householders to
recycle rubbish;
recycling is cheaper if householders sort their own waste;
recycling will not continue if there is no demand for recycled
goods
Composting
4. Define composting – aerobic decomposition of BIODEGRADABLE
material.
5. How does it help in terms of recycling? It recycles organic household
waste into humus-like soil. It returns valuable nutrients to the soil.
Landfills and Incineration pp. 240-241 – know all
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16
IB Qs
6. Which of the following pairs are both examples of recycling? C Notes
A.
Manufacturing new aluminum cans from old ones; biodegradation of plastic
bags
B.
Processing newspapers into toilet paper; breaking down of raw sewage in the
oceans
C.
Converting used car tires to rubberized road surfaces; producing compost
from organic waste
D.
Producing methane from landfill sites; incinerating plastics
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7. The table below shows the different types of domestic waste and the amounts produced
per capita each year in a city in a developed country.
Material type
Examples
Waste produced
per capita / kg yr–1
Organic material
garden waste, food/kitchen waste, wood
Paper
newspaper, writing paper, packaging,
cardboard, milk cartons
91.2
Plastics
soft drink bottles, plastic bags, plastic
containers
25.1
Glass
jars, bottles, plate glass
23.9
Metals
steel cans, aluminium packaging and
cans, copper pipes
14.4
Household hazardous
paint, dry cell batteries, car batteries,
fluorescent light bulbs
1.9
Miscellaneous
ceramics (bricks, tiles etc.) rock, ash, soil
Total
188
10.2
354.7
[Based on Australian Bureau of Statistics data]
(a)
(a)
Calculate the proportion of paper, glass, plastics and organic material
combined as a percentage of total waste.
(b)
Outline and evaluate strategies for the management of the domestic waste in
the table above.
100 ×
(91.2  23.9  25.1  188)
= 92.5 %; (accept 92.0 to 93.0 %)
354.7
(b)
Outline
 most of the waste generated can be recycled or composted
 some of the waste could be reused e.g. jars/bottles/textiles
Evaluate
 composting and recycling would significantly reduce the amount
of domestic waste going to landfill/combustion
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 the advantages of reducing landfill should be explained to
householders
 incentives may be necessary to encourage householders to
recycle rubbish
 recycling is cheaper if householders sort their own waste;
recycling will not continue if there is no demand for recycled
goods;
8. The diagram below shows amounts of waste being recycled or sent to landfill in
Australia between 1993 and 2002.
Key:
8
Waste to landfill
Recycled materials
7
6
5
Mass/
×105 tonnes
4
3
2
1
0
1993
1994
1995
1996
1997 1998
Year
1999
2000
2001
[Source: adapted from
www.environmentcommissioner.act.gov.au/_data/assets/image/12231/graph2_03.jpg]
(a)
(b)
(i)
State, to the nearest hundred thousand tonnes, how much material was
recycled in Australia during 2001.
(ii)
Explain why the amount of waste sent to landfill in Australia has
remained relatively constant since 1994 despite the increase in
recycling.
(i)
Outline two ways in which technology can reduce the amount of solid
domestic waste that is sent to landfill within a country.
1
2
19
2002
(ii)
(a)
(i)
Explain why the technological solutions you have described in part
(b)(i) may still have negative environmental effects.
400 000 (tons)
(ii)
* total amount of waste produced has increased but a larger
proportion is now recycled :
reasons :




as demand for goods increases people consume more
economic/industrial growth so more waste produced
increase in packaging over time
some products cannot be recycled so will still have to be
sent to landfill
 increase in population has lead to more consumption
 some people simply do not bother to recycle
(b) (i)




recyclable packaging (e.g. cartons/recycling bins/devices)
transporting waste to other countries;
incineration technology;
manufacturing goods which can be recycled;
(ii)



collecting recycling still uses petrol/energy
waste is sent elsewhere but still contributes to global economic
footprint;
incineration produces atmospheric pollutants;
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5.6 Depletion of Stratospheric Ozone pp. 242- 248
Ozone and temperature :
10. Fill in the blanks : the ozone is found between approximately ___10____ to
___50_____ km with the highest concentration found between about __20___ and
__30__ km. This is found mainly in the lower ___strato______sphere and causes the
temperature to __increase_____ with a(n)_____increase_________ in altitude.
IB Qs True or False : mark T or F . If false rewrite statement to make it true:
11.
Ozone gas is increasing in the upper atmosphere through the action of CFCs –
F ; decreasing
12.
Ozone gas is increasing in the upper atmosphere because of global warming –
F ; decreasing
13.
Ozone gas is decreasing in the upper atmosphere because of the increase in the
amount of nitrogen oxides produced by the combustion of fossil fuels – T see
text p. 246
14.
The formation of ozone involves the absorption of ultra-violet radiation – T
see text p. 243 : UV radiation breaks down oxygen atoms to combine with O2
resulting in O3 = ozone.
.
15.
The type of ultra-violet radiation absorbed by the ozone layer does not affect
living organisms – F does affect
16.
Chlorofluorocarbons in the stratosphere are rapidly broken down allowing
them to escape into the outer atmosphere – F p. 244 : rapidly broken down by
UV radiation in stratosphere allowing them to release Halogen atoms ( Cl, F
and Br).
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17. True or False : Ozone is destroyed by carbon dioxide released by burning fossil
fuels – F nitrogen oxide.
18. The ozone layer can be protected by B
I.
using substitutes for ozone-depleting chemicals.
II.
reducing cattle production.
III.
recycling old refrigerators.
A.
I and II only
B.
I and III only
C.
II and III only
D.
I, II and III
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19. The figure below shows the mean October ozone concentrations recorded at the
Halley research station, Antarctica, over a 45 year period.
350
300
250
200
Dobson units
150
100
50
1950
1960
1970
1980
1990
2000
2010
Year
[Source: J Shanklin, British Antarctic Survey, in Climate Change, 2001, Royal Society of Chemistry]
(a)
(i)
Describe the trend in ozone concentration in the figure above.
(ii) Suggest reasons for the trend you have described in (a) (i).
(b) Outline the role of ozone in the absorption of ultraviolet (UV) radiation.
(c)
State one negative consequence to humans of exposure to UV radiation
and one negative consequence to plants.
Humans
Plants
(d)
Outline three methods of reducing the quantity of ozone depleting
substances in the environment.
1
2
23
3
ANSWERS :
(a)
(i)
ozone concentration has declined
(ii)
increase of halogenated gases – CFCs in the atmosphere
inhibiting the production of ozone.
(b)
UV radiation passing through the Earth’s upper atmosphere is absorbed
by the formation and destruction of ozone.
(c)
humans: genetic mutation/skin cancer/cataracts/impaired
immune system.
plants: reduced photosynthesis/reduced crop yield due to cell damage.
(d)





use inert gases in refrigeration units
do not use halogenated organic gases - CFCs to blow insulation foam
recycle harmful gases
dispose of appliances such as refrigerators safely (removing gas)
setting national and international limits on halogenated organic gases - CFCs
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Notes Ch. 5 – Part 3
1. What are the common names for the troposphere and stratosphere?
Lower atmosphere , upper atmosphere
2. What is the difference between ozone found in the troposphere versus
that found in the stratosphere? ( include how each is formed in your
explanation)
Ozone in troposphere is a pollutant and forms as a result of pollution by volatile
organic compounds ( VOC’s) , hydrocarbons and nitrogen oxides ( NOx )
Ozone in stratosphere is considered a protective layer against UV radiation. It is
formed by sunlight ( UV radiation) splitting oxygen molecules into atoms which
regroup to form ozone.
3. What does VOC stand for? How do they react? List some examples.
volatile organic compounds – evaporate into gases and take part in photochemical
reactions. Methane, ethane and alcohol.
4. Nitrogen Oxides : remember that these can also deplete ozone ( ODS – ozone
depleting substances) in the stratosphere ( upper atmosphere) although they help
form the ozone in the troposphere ( lower atmosphere).
5. Use the following to explain the reaction that causes urban haze commonly
known as smog: fossil fuel, nitrogen monoxide, oxygen, and nitrogen dioxide.
Fossil fuels burn and produce nitrogen monoxide. Nitrogen monoxide reacts with
oxygen in the air to produce nitrogen dioxide a brown gas that contributes to urban
haze – smog.
6. List damage done by tropospheric ozone on crops and humans: damages crops,
irritates eyes, causes breathing difficulties, susceptibility to infection. It is highly
reactive and can attack fabrics and rubber materials. Can cause up to 15% reduction
in lung capacity in children born and raised in areas of high level of ozone.
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7. Photochemical smog is formed when primary pollutants interact with which of the
following? D
A.
Water vapour
B.
Heat
C.
Oxygen
D.
Sunlight
8. Which factor greatly increases the likelihood of photochemical smog forming over a
city? C
A.
Low altitude
B.
High rainfall
C.
Thermal inversion
D.
Short daylight hours
9. Which statement about photochemical smog is correct? Notes and test D
A.
Photochemical smog is independent of local topography and climate.
B.
Photochemical smog is a mixture of snow and rain formed when the upper air
temperature is below freezing.
C.
Photochemical smog results from the meeting of two air streams in areas of
low pressure.
D.
Photochemical smog is a mixture of pollutants formed under the influence of
sunlight.
Know the Following:
Major Green house gases : water vapor, CO2 , nitrous oxide, methane, CFCs and
ozone.
10. What is the difference between dry deposition and wet deposition? Explain
using examples.
26
11. Explain the formation of acid rain.
27
Effects of Acid Rain
12. List the characteristics of an acidified lake
13. How does acid rain cause high levels of mercury or aluminum in fish? How
can this harm humans?
14. Explain the effect ( in detail) of acid rain on coniferous trees and
subsequent loss of NEEDLES:
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15. Define leaching
In general, leaching is the extraction of certain materials from a carrier into a liquid (usually, but not
always a solvent). Specifically, it may refer to:


Leaching (agriculture), the loss of water-soluble plant nutrients from the soil
Acid rain leaches calcium and other nutrients - minerals form the soil
16. Explain why the effects of acid rain are regional rather than global. In other
words, areas affected by acid rain have what in common? Done for you:





These areas are usually around industrialized cities
They are DOWNWIND of dense concentrations of fossil- fuel power
stations, smelters ( steel mills) and large cities.
They have high rainfall
They have lots of forests, streams and lakes
They have thin soils
The main trend in the distribution of acid deposition is due to increased sulfur
emissions in newly industrializing countries ( NICs) and in developing countries. In
China, the worst affected areas have been in the south – the Pearl River Delta. In
South Africa, coal-burning power stations and large metal working industries are
concentrated in the Eastern Transvaal Highveld.
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Management of Acid Deposition – Know the following:

Add chalk - limestone ( Calcium carbonate) to neutralize acid rain in
lakes
30
17. Which of the following is not a result of acid deposition from burning of fossil fuels? D
notes
A.
Leaching of calcium from soils
B.
Death of coniferous trees in forests
C.
Killing of fish due to high levels of aluminium in lakes
D.
Thermal expansion of oceans
18. Lime was put into Scandinavian lakes in the 1980s as A
notes
A.
a response to acid rain from the combustion of fossil fuels in other European
countries.
B.
an attempt to replace nitrogen lost by excessive harvesting of fish.
C.
an attempt to combat eutrophication caused by excessive local use of
fertilisers.
D.
a waste product from local industrial processes
19. Which method would be most effective in reducing the acidity of rain downwind of a
coal-fired power station? C notes
A.
Burning high sulfur coal
B.
Increasing the temperature at which fuel is burned
C.
Fitting wet scrubbers (filters) to chimneys
D.
Converting the power station to burn high sulfur oil
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