File 2 ess-important essay question asnwer

ESS ESSAY QUESTIONS -

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1. Describe a method for measuring changes in abiotic components in a named ecosystem affected by human activity. [6)

Human activity in a named ecosystem.

• e.g. changes in microclimate due to deforestation in a temperate forest area;

Abiotic factor

1. Measure ground temperatures using a thermometer/temperature sensor;

2. Measure light intensity using a light meter/sensor;

3. Measure wind speed with an anemometer/wind speed recorder;

Additional information on method.

1. Compare readings for an area that has been deforested with an area that is

intact;

2. Repeat readings over a period of time in order to calculate averages;

sampling technique used e.g. transect/quadrat & results extrapolated;

2.Describe ecocentric and technocentric responses to global warming and justify which may be more effective in reducing the impacts of global warming. [7]

Ecocentric responses:

1. Ecocentrism stresses the minimum disturbance of natural processes so

ecocentrics would advise reducing greenhouse gas emissions so as not to

unbalance the natural greenhouse effect;

2. Ecocentrism stresses self imposed restraint on resource use;


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• e.g. individuals reducing their carbon footprint by walking to work;

Technocentric responses:

1. Technocentrism stresses that technology can provide solutions to

environmental problems;

2. Technocentrics would support investing in alternative technologies;

• e.g. nuclear/solar/carbon capture and storage to reduce atmospheric

carbon;

3. Technocentrism stresses the importance of market and economic growth;

so technocentrics would support carbon trading/economic advantages of

trading in low carbon technologies;

3.Outline the environmental impact of two named food production systems.

[4]

e.g. For wheat cultivation in California

• Environmental impact:

1. Compaction of soil due to use of heavy machinery leading to soil erosion;

high level of human inputs, agrochemicals/machinery, so soil structure is

lost;

2. Topsoil is more easily removed by the agents of erosion (wind/water);

3. once topsoil is lost, organic material is gone and the fertility of the soil is

reduced;

4. Over-irrigation can lead to salinization of soil;


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5. Run-off of agrochemicals/fertilizers into water bodies/rivers/lakes leading

to eutrophication; Pesticides run-off into lakes/streams and build up in

tissues of organisms (bioaccumulation); e.g. For beef livestock in

Argentina

• Environmental impact:

1. Livestock can trample the vegetation leading to loss of vegetation/exposed

soil;

2. Loss of biodiversity as only hardy vegetation can grow once soil has been

trampled;

3. Exposed soil is more easily eroded;

4. Habitat lost as forested areas are cleared so that the grass can be grown for

the livestock to eat;

4.Explain the relationships between population growth, social systems and food production technologies. Refer to named contrasting countries in your answer. [9]

Countries ; Uganda & UK

1. High population growth is usually in countries of high rural population e.g. Uganda;

2. Low population growth is in countries with a low rural population e.g. UK;

3. Uganda needs many children to work in the subsistence farming they practice;

4. The low level of technology in the farming system means that the labour needed is high

and so the fertility rate is high

5. 5.UK affords to feed its population, with a surplus, despite having changed from labour

intensive to capital intensive farming;

6. 6.Subsidies in MEDCs lower production costs, encouraging increased food production


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7. 7.LEDC/Uganda exports large volume of food produce at low costs to MEDC/UK (which

then adds value to the produce) but this benefits only a small percentage of the rural

population in LEDC;

8. 8.UK has less than 5 % of the population working in farming so not many children are

expected or want to work in farming;

9. .High levels of mechanization mean few people are needed on the farm (population

growth is linked to other factors);

5.Describe the role of any two named historical influences in the

environmental movement. [3]

1.(a) e.g. Rachel Carson and her book A Silent Spring:

• raised awareness of the threat of the pesticide DDT to organisms high up the

food chain;

2.e.g. Greenpeace 1970s:

• direct action to prevent whaling;

•

3.e.g. Chernobyl nuclear meltdown 1986:

• reinforced negative perceptions of nuclear power in society;

6.Describe and evaluate ecocentric and technocentric responses to

eutrophication. [8]

• Description of ecocentric responses:

1. responses will try to minimize the impact on the environment by encouraging

people to be restrained;

2. using methods which are more in harmony with natural systems;

3. e.g. use of organic fertilizers/manure on agricultural fields;


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4. e.g. practice of mixed cropping/crop rotation so less or no fertilizers are

needed;

5. e.g. educational campaigns to encourage people to use less detergent/more

environmentally friendly detergent;

6. e.g. plant a buffer zone between the fields and the water courses to absorb any

run-off;

Evaluation: [4 max] 1. people are reluctant to adapt lifestyles/accept lowered standard of living so

ecocentric approaches can be hard to enforce;

2. alternative approaches e.g. organic fertilizers/manure may not work so

effectively/can still cause run-off and eutrophication;

3. technocentric solutions may increase the costs of e.g. detergents/may require

a financial commitment;

4. technocentric can be a short term solution but is unsustainable;

5. technocentric solutions may not be an option in less-developed areas/for less

wealthy farmers;

7.Evaluate the relative importance of factors that determine the sustainable use of freshwater resources. Refer to at least one case study in your answer. [6]

Award up to [3 max] for identifying factors: Political conflict; population size/growth / migration levels; Industrialization; increased food production / irrigation; Socio-economic levels / levels of development; cultural attitudes towards

Definition of sustainable use: Using water at a rate which allows natural replenishment/regeneration; using water in a way that minimizes damage to the environment; Evaluation of relative importance:


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1. The relative importance of different factors will depend on the context of the

area; in semi-arid/desert areas there is a smaller stock of water resources in the

first place;

2. Conflicts over water can be made worse when there are political tensions

between different user groups; or in societies with a short-term attitude toward

resource use;

3. In countries near to carrying capacity, population numbers will be more

significant than in countries where water supplies are abundant;

4. In countries where water is abundant it may be perceived as an unlimited

resource and therefore wasted;

5. In societies where there is good awareness of sustainability issues individuals

may take steps to ensure their own level of water use is sustainable e.g. recycling

rain water;

6. In countries with oil resources technological solutions to water shortages such

as desalinization are a more affordable option; in LEDCs expensive high tech

solutions are less of an option;

Award up to [2 max] for use of appropriate illustrative case study/examples. e.g. Aral Sea – short-term gain in cotton industry at expense of sustainable water use; e.g. Colorado river – drastically reduced flow due to high consumption/wasteful abstraction of groundwater resources; [9 max] Do not accept vague or general examples e.g. dry in Africa.


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8.Discuss, with reference to two contrasting environmental problems, the technocentric belief that technology may provide solutions to environmental problems. [7]

Candidates can approach this question in a number of ways, and responses will depend on the choice of environmental problems. Note: Although the assumption is that the environmental problems are from the Environmental Systems and Societies course, a candidate who chooses to respond to any environmental problem e.g. a natural hazard such as the tsunami or flooding, should still be credited. Award [1] for two contrasting environmental problems. Contrast may be one of cause or scale:

e.g. ozone depletion and loss of biodiversity;

Discussion: Ozone Depletion:

1. Technocentric responses played a key role in solving ozone depletion; alternatives to gas-blown plastics/propellants/methyl bromide enabled products to be produced without releasing so many ozone-depleting substances; so technology enabled societies to continue lifestyles they had become accustomed to;

2. However, without the Montreal Protocol international agreement to set limits, there would have been little likelihood of governments taking the necessary steps to produce these alternatives; so a political solution was important as well as a technological one;

Technological solutions have played some role in the response to the loss of biodiversity;


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1. Web-based monitoring systems have helped to monitor species numbers; satellite tracking of migrating organisms, e.g. whales / sea birds;

2. ICT systems have been important in enforcing agreements such as CITES; and sophisticated technological solutions like seedbanks enable us to preserve DNA so that valuable genetic diversity is not lost;

3. However some might argue that technologies e.g. GM crops are actually responsible for the loss of species diversity; and many of the causes of species loss e.g. habitat degradation are occurring in societies with little access to technology and it cannot play a role in solving these problems; 4.Technology is a tool which cannot on its own solve any problem, there has to be political will to make changes and then technology can help to provide solutions;

Evaluate the anthropocentric view that it is important for everyone in society to participate in environmental decision-making. Discuss one example of the successful involvement of communities in solving environmental problems [9]

Award [4 max] for evaluation of view. Strengths of view that participation is important: 1.Participation has an important role to help educate people about environmental issues; 2.Participation means that people who may be causing the problems are less likely to do so if they are involved in decisions about their own environments; 3.Sometimes poorer/less powerful/marginal groups in society have the best knowledge about what is right for an environment e.g. indigenous groups, and if they participate their knowledge can be shared;


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4. People who believe in democracy argue that everyone has a right to have a say in how communal resources/environments are managed; 5. Ecosystems need to be managed holistically so people from all walks of life who have useful skills can contribute; Weaknesses of view that participation is important: 1.Sometimes leadership needs to be taken by political groups to ensure change happens; 2.Too many people being consulted can slow down progress when the need for action is urgent; 3.Many groups in society may not care about the environment or see it as important; Award [1] for an example of successful community project: e.g. tree planting in Nepal;

Award [3 max] for any relevant points discussing the project: Villagers provided with seedlings / individual responsibility for protecting forests given to local community groups;

A) Forests provide fuel wood resources for villagers;

B) Soil also conserved as forests protect from erosion;

C) Communities benefit directly from standing forest reserve and are therefore more likely to participate in protecting trees as they grow; [8 max]

Accept responses which use Skåne Biosphere Reserve as an example of community involvement. Do not accept “communities reaching international agreements e.g. Kyoto/Montreal protocols” as a valid example of involvement of communities unless the discussion explains how communities are involved at a local level. All


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solutions to environmental problems will involve groups of people so the expectation here is that responses will be an example of the involvement of LOCAL people in a “community project.”

9.Discuss, with reference to examples, the influence of cultural, political and

economic challenges to pollution management. [5]

Cultural: 1.Capitalist societies often consider the profit over the environmental damage of the pollution; often they would rather follow step three, when caught, than the other steps, as this may seem cheaper; 2.Rural society, with low population density has an “out of sight” mindset, with pollution not being a problem if you cannot see it; 3.Pollution tolerance levels vary from society to society; some types of pollution are more tolerated than others by a particular society/culture; e.g. noise or visual pollution in a rapidly urbanising city/area are accepted; Political: 4.Less developed countries are often willing to allow pollution to encourage local Industry; 5.The dumping of toxic waste from MEDCs to LEDCs is sometimes allowed by the governments/as the result of corruption;


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6.Lower standards for pollution to encourage industry are acceptable in certain countries/areas; 7.A political blind eye is often turned if the industry is profitable/paying taxes/creating jobs; 8.LEDCs often do not have the resources to enforce the laws which they do have in

place

9.Rich countries can have a “throwaway” society and so generate a large amount of wastes/pollution; but they also value a clean and tidy environment so pollution is not tolerated; 10.Waste pickers;

LEDCs can only afford old polluting equipment; LEDCs have no money for technology to clean up pollution; UN protocols not ratified/signed as countries fear it may slow economy;

e.g. USA and Kyoto protocol; 11.As countries develop there is a trend to spend more money on pollution prevention; 12.LEDCs want MEDCs to pay for the costs of the pollution caused by MEDCs which affect whole world; 13.Movement to push for transfer of technology from MEDCs to LEDCs to prevent/ reduce pollution; [9 max] Responses should contain at least one point for cultural, political and economic factors. Award [7 max] if no examples are used. Award [6 max] if one factor is not mentioned. Award [3 max] if two factors are not mentioned.


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10.Discuss how development policies and cultural influences can affect human population dynamics and growth. [6]

Development policies: Policies that target reduced death rate e.g. improved public health and sanitation; e.g. access to a clean water supply; e.g. increased food supply; e.g. vaccination/immunization programmes; e.g. increased education for children to improve nutrition/farming/healthcare; these policies can increase population growth; An increased life expectancy can increase the population growth as fewer people die;

improved health care increases the ageing population and thus the population of a country;

Policies that target fertility: incentives to have children; e.g. generous maternal benefits; disincentives to have children; e.g. fines for having extra children above the approved government number; increased education for girls often decreases fertility; e.g. later marriage / more child spacing / more use of birth control / family planning; anti-natal policies decrease population growth / pro-natal policies increase population growth; the Chinese government actively discourages births/one child policy; policies can encourage immigration to facilitate gap in labour market in falling birth

rate countries;

Cultural influences: cultural/religious influence on contraception usage/non-usage can increase/decrease

fertility; education on birth control and contraception usually decreases fertility; boys being more valued than girls in some cultures so increase fertility so more boys

are born; the culture of having children to support in old age/help farm the land; marriage patterns – marrying young usually means increased fertility;

10.Outline the basic components of an ecosystem using the systems approach. [4]

Inputs of energy and matter;


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Outputs of energy and matter; Ecosystems are an open system; Matter is recycled; The amount of matter in the biosphere remains constant;

Energy enters (an ecosystem) as light; Energy transferred in matter e.g. food web; Energy leaves (an ecosystem) as heat; Appropriate use of entropy concept; Inputs of producers/consumers/decomposers/water/soil etc.;

Outputs of producers/consumers/decomposers/water/soil etc.; Within the ecosystem the cycling/processing of

producers/soil/water/nutrients; [4 max] Do not credit any reference to energy being recycled. Award credit if examples are used correctly for inputs/outputs and processes

11. Evaluate the advantages and disadvantages of two contrasting energy sources and discuss the economic factors that affect the choice of these energy sources by different named societies [7]

Award [1 max] if two contrasting energy sources are named – these should be one renewable/replenishable and one non-renewable. Nuclear could be used with any other energy source

e.g. solar and coal energy; Advantages of solar:

No polluting gases such as 2 X CO /NO or X SO ; Source is renewable/replenishable and potentially infinite; safe to use; Individual supplies to houses so can be used in rural areas;

Disadvantages of solar: Expensive to make the solar panels;


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is a discontinuous supply / none at night and so needs storage; not all areas of the world are suitable;

Advantages of coal: There is still a large supply / 250 year’s worth of coal left in the world; Technology is set up to use coal in industry/electricity production; As a solid it is easy and safe to transport; It is relatively cheap to mine and burns/combusts to create electricity/heat;

Disadvantages of coal: As a non-renewable resource it will eventually run out; Combustion releases polluting gases 2 X CO /NO or X SO ; Degradation of land due to mining;

Award [4 max] for any reasonable evaluation. Responses must evaluate each advantage and disadvantage rather than a general list or one word answers. The structure of the answer should flow rather than be split into sub headings. Lists and sub headings would be penalized in the expression of ideas marks. Award [1 max] for at least two clearly named societies. Named Socities: e.g. biogas in India and coal in China;

Economic factors: China is committed to using coal in heavy industry and electricity

production, to change would cost too much; China has plentiful supplies of easily available coal; Electricity from burning coal is cheap for China; Small scale biogas generators are easy to build; They use local biomass, from cattle, to fuel the biogas generator, so it is

cheap; It is too costly for these Indian villages to connect to the main electricity

grid; [9 max] Award [4 max] for any reasonable society and economic factor given.


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12.Explain the relationship between succession and equilibrium.

Succession is the change in the community of an area over time until the climax

Community of that biome is reached The more diverse an ecosystem the more stable it is; Succession increases diversity and so stability increases; Each stage/sere of succession helps create a deeper and more nutrient-rich

soil, so allowing larger plants to grow; This increases the habitat diversity which leads to greater species and

genetic diversity and thus greater stability;

Climax communities/seres have a more complex system which is more stable; more complex food webs have greater diversity, so more stability if one organism goes extinct;

Humans often try to recreate pioneer seres in agriculture, these are less stable and so humans have to constantly monitor/work with the crops;

Monocultures in agriculture are more vulnerable to disease and pests and

so less stable; succession can be interrupted naturally and by humans and this also reduces the stability of the ecosystem;

e.g. humans have tried to stop fires in Mediterranean biomes but when fires break out they are far more damaging to the diversity than the natural fires would have been; [6 max] Award credit to examples that clearly show the link. Award [1max] for a clear definition of succession.

13.Compare the likely views of a Deep Ecologist and a Cornucopian on the exploitation of oil reserves in a pristine (untouched) environment.

4. Values system spectrum/continuum;


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5. Deep Ecologists would probably be opposed to the exploitation of oil reserves /Cornucopians are likely to support it;

6. Deep Ecologists would be concerned that nature will be damaged,

and that it is more important than material gain for its own sake;

7. Cornucopians feel that resources are there to be exploited/generate income; and that with sufficient ingenuity/technical expertise, potential environmental obstacles could be overcome/technocentric approach;

8. Deep Ecologists would favour the rights of species to remain

unmolested over the rights of humans who wish to exploit resources for economic gain;

9. Deep Ecologists distrust/lack faith in the modern large-scale

technology; and its associated demands on elitist expertise (which would be required for oil exploitation);

14.With reference to natural cycles and human activites,outline the process of eutrophication

1. Eutrophication is an increase in nutrients in an aquatic ecosystem; 2. Nutrients added from decomposing biomass / natural run-off from

surrounding 3. areas (natural cycles); 4. Seasonal temperature inversion/turnover/upwelling currents bringing

nutrients to surface (natural cycles); 5. Similarly run-off from agricultural land/artificial fertiliser/fertilisers/slurry

adds 6. nutrients to water (human activities); 7. Domestic waste water contains phosphates and nitrates/detergents/non-

treated 8. sewage(human activities);


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9. [3 max] for causes and [2 max] if only natural or human causes are mentioned .

1. Both human and natural eutrophication leads to increase in biomass of algae initially/rapid algae growth;

2. The algae increase turbidity/lower the light penetration to underwater plants;

3. Increased death of algae/underwater plants leads to increase in DOM/bacteria;

4. Increased bacteria increase BOD which leads to lowered oxygen content of water/causes hypoxia;

5. Lowered oxygen leads to stagnation/anaerobic bacteria/death of many organisms;

6. Human induced eutrophication happens a lot faster than natural eutrophication/on a bigger scale;

15. Explain how eutrophication illustrates both positive& negative feedback systems [5] For full credit in describing feedback, responses should identify two steps. Step 1: how change in one factor causes change in another; Step 2: how the second factor effects the first, either increasing its change (positive feedback) or decreasing its change (negative feedback). Positive feedback [2 max]:

1. As more nutrients are added to the system, biomass of algae increases due to nonlimiting nutrients;

2. Decomposition of increased biomass leads to further nutrient load and so

further deviation from equilibrium / positive feedback occurs;

3. Growth of algae block light so causing underwater plants to die and create more nutrients; more nutrients leads to further growth of algae so further deviation from equilibrium / positive feedback occurs;


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4. Increase in BOD/bacteria causes oxygen-dependent/sensitive organisms to

die;this increase in DOM leads to even further increase in BOD/bacteria so further deviation from equilibrium / positive feedback occurs;

Negative feedback [2 max]:

5. Increase in nutrients promotes growth of plants/algae that fix/store them in biomass; this leads to a reduction in nutrients so balance is restored/negative feedback occurs;

6. Increase in algae/phytoplankton will lead to increase in zooplankton/algal

feeders; which may lead to subsequent decrease in algal populations so balance is restored/negative feedback occurs;

7. Increase in dead organic matter provides more food for decomposers which increase in number;Increased rate of decomposition leads to a decrease in dead organic matter so balance is restored / negative feedback occurs;

15.Outline how culture ,economic and technology have influenced the value of a named resource in different regions or in different

historical periods [7]

for example, Whales as a resource; how value changed valuable resource prior to

1920/extensively harvested; lost value as petroleum products/fossil fuel oil/plastics

became cheap and available;

Influence of culture: Different regions of the world value them differently e.g. Inuit value them spiritually and

as food/oil resource; nowadays, generally valued for their biodiversity; now valued from

ethical and moral/aesthetic point of view; some countries /Japan/Norway still hunt

whales for scientific purposes;

Influence of economics: In past valued economically as food/oil resource; now valued economically for tourism;


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Influence of technology: Pre fossil fuels, technology allowed for oil to be extracted from whales; now technology

in place to exploit fossil fuels, so whales less significant for this purpose; change in

fishing/harvesting technology allowed populations to plummet;

For example. uranium as a resource; How value changed prior to splitting of the atom no known use/value; increased in value

during 20th century as value of nuclear energy became understood;

Influence of culture: There was a shift in values from acceptance to reluctance as the dangers became

clearer; ethical values regarding uranium have shifted over time depending on historical

events e.g. nuclear bombs/tsunami impacts in Japan; awareness of role of fossil fuels in

global warming may have shifted interest in favour of nuclear energy for some

societies/countries;

Influence of economics: Industrialisation/economic development led to increased significance/value of

centralised energy supply; initially seen as a clean, cheap source of energy;

Influence of technology: As nuclear technology has been developed, uranium value has increased;

as technology for producing nuclear energy/nuclear fission/nuclear bomb has

developed so value has increased; shifts in technology to find reserves therefore shifting

the value of regions where resource is found;

Award [1 max] for named resource; [2 max] for how its value changes


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historically or geographically; and [4 max] for explanation of influences on

its value. Award [4 max] if only one influence is addressed. [6 max].Award

credit for description of specific examples/case studies.

Advantages of Global Warming

Arctic, Antarctic, Siberia, and other frozen regions of earth may experience more plant growth

and milder climates.

The next ice age may be prevented from occurring.

Northwest Passage through Canada's formerly-icy north opens up to sea transportation.

Less need for energy consumption to warm cold places.

Fewer deaths or injuries due to cold weather.

Longer growing seasons could mean increased agricultural production in some local areas.

Mountains increase in height due to melting glaciers, becoming higher as they rebound against

the missing weight of the ice.

Boundary disputes between countries over low-lying islands will disappear.

Warmer temperatures are more conducive to certain species of plants and animals

• The redistribution of rainfall means that some areas which were prone to drought will receive

increased rainfall and others that were prone to flood will receive less rainfall

• Warmer temperatures have melted extensive areas of permafrost, especially in Siberia where

one million square kilometres of previously frozen ground has thawed. This has opened up new

land for agricultural purposes.

• The melting of mountain glaciers has increased the volume of water in some rivers, including

the Yangtze, Brahmaputra and Ganges. This means more water has become available for upland

irrigation schemes and human consumption.

• Some crop species grow better in warmer conditions and this has raised productivity yields.

• Warmer temperatures are, on the whole, better for human health than colder ones.

http://geography.about.com/b/2010/03/24/another-advantage-to-global-warming.htm


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• The warmer climate has extended growing seasons in some areas. Previously there were

places where only one harvest could be raped in a year but now it’s possible to reap an early

and late harvest.

• Less ice in the polar regions has opened up the possibility of oil and mineral extraction. The

Russians were the first to identify this opportunity when they claimed part of the Arctic sea bed

as Russian territory.

• The northwest and northeast passages have become navigable at times meaning that shipping

between the Arctic and Pacific can now go to the north of Canada or to the north of Scandinavia

and Siberia.


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SOME IMPORTANT ESSAY QUESTION

1. Explain how different types of atmospheric pollution may have negative effects on

terrestrial ecosystems. Refer to at least two named atmospheric pollutants in your

answer

2. Identify the ways in which unsustainable agricultural practices may lead directly

and indirectly to a loss of biodiversity

3. Discuss why some of the effects of global warming may be seen as beneficial to

human societies.

4. Describe how the Gaia concept might be applied to pollution

5. With reference to examples, distinguish between the terms succession and

zonation.

6. Explain why some people believe that the ecological footprints of some countries

needt o be reduced. Justify whether an ecocentric or a technocentric approach to

reducing the ecological footprint is more likely to be successful

Date post:	25-May-2015
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