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            5 Soil systems, terrestrial food production systems, and societies

Topic 5 raises issues concerning diflerent methods of food production. Are the intensive methods of food production carried out in many MEDCs detrimental to the environment, or are they in reality the best way to provide food for ever-growing populations?


Do intensive farming methods, in fact, have environmental benefits? Intensive chicken farming (broiler production systems), for example, has been shown to produce a lower carbon footprint than free-range/organic methods. What ethical issues do diflerent types of animal feed production raise?

This topic also provides points for discussion concerning our perception of time compared to the time scales that environmental systems operate under. Fertile soil can be considered as a non-

renewable resource because once depleted, it can take significant time to restore the fertility: how does our perception of time influence our understanding of change?

Case study

Food deserts

Food deserts are areas without ready access to fresh, healthy, and affordable food. These communities may have only fast food restaurants and shops that offer few healthy, affordable food options. Such factors contribute to a poor diet and can lead to high levels of obesity, diabetes and cancer.

A food desert is a geographic area where affordable and nutritious food is dificult to obtain, especially for those without a car. The term ‘food desert’ can be defined as any census area where at least 20 per cent of inhabitants are below the poverty line and 33 per cent live more than a mile from a supermarket.

According to the US Department of Agriculture (USDA), 10 per cent of the USA is a ‘food desert’. It claims that there are thousands of areas where low-income families have limited or no access to healthy fresh food. The concept of

‘food deserts’ was originally identified in Scotland in the 1990s.


They are associated with urban decay and are characterized by numerous fast-food restaurants and convenience stores serving fatty, sugary junk food to overweight consumers.The USDA links food deserts to a growing weight problem. In the USA, childhood obesity has tripled since 1980. The annual cost of treating obesity is nearly $150 billion.


Critics note that only about 15 per cent of customers shop within their own census area and that the focus on supermarkets means that the USDA ignores tens of thousands of larger and smaller retailers, farmers’ markets and roadside greengrocers.

An example of a food desert is found in the South Side district of Chicago.


Though crisps, sweets and doughnuts are easy to come by, fresh fruit is a rare commodity. Nevertheless, between 2006 and 2011, due to the arrival of some new grocery stores, Chicago’s food desert decreased by 40 per cent. It sometimes takes only one shop to make a big difference – the Food-4-Less store in Englewood improved access to fresh food for over 40 000 people. Moreover, the opening of a decent grocery store can have a multiplier effect and lead to the arrival of other better-class shops in the area, which in turn fuels a local economic revival.



















                           6 Atmospheric systems and societies


This topic examines the atmospheric systems that control and regulate climate systems. It also explores the eflects that human societies have had on these systems (e.g. through pollution). International meetings have endeavoured to limit the emissions of pollutants that have an adverse eflect on the atmosphere. To

what extent have international agreements such as the UN-organized Montreal Protocol (pages 327–328) been successful? Unless treaties are legally binding, is there any point in countries signing up to them? Can one group or organization decide what is best for the rest of the world?


Natural pollution?

Are all forms of pollution necessarily human in origin? No. Many are natural. Some, like acidification,

may be completely natural in some areas and anthropogenic in others. However, it is the case that acidification is largely related to human activity. It is an ‘industrial form of ruination, which pays little heed

to international boundaries’. Many countries produce acid pollutants and some export them. Nevertheless, there are natural causes of acidification – bog moss secretes acid, heather increases acidity, and conifer plantations acidify soils. Volcanoes are important sources of atmospheric pollution – especially sulfur dioxide and hydrogen dioxide.

For example, before the eruption of the Soufrière volcano, Montserrat had some of the finest cloud forest in the Caribbean, but by 1996 vegetation loss from acid rain, gases, heat, and dust was severe. In 1996, the pH of the lake at the top of Chances Peak was recorded at 2.0 (i.e. 1000 times more acidic than a pH of 5.0).



















Acid rain caused by volcanic eruption





















Vegetation destroyed by a combination of acid rain, sulfur emissions and lahars (mudflows) from the Soufrière volcano, Montserrat.

Case study

Atmospheric pollution and the ‘prisoners’ dilemma’
















Someone else’s problem – atmospheric pollution in one country leads to harmful effects on the environment elsewhere.

The ‘prisoners’ dilemma’ model (aka the Nash equilibrium, after the mathematician who developed it) can be used to explore the ethical issues involved in atmospheric pollution, and the ways in which these problems can be resolved. Non-point source pollution (page 50), such as that produced by the combustion of fossil fuels leading to acid rain, may mean that an individual polluting a common resource suffers little. Indeed, such an individual may even benefit from their disposal of pollutants, but the non-polluting users of the resource are affected by the pollution and they do not benefit in any way. For example, atmospheric pollution produced in the UK and carried to Scandinavia has led to the destruction of fresh water ecosystems (fjords) there. There is, therefore, a benefit for those who continue to pollute. This conundrum underlies many issues regarding the management of non-point pollution, from local (e.g. a lake) to global (e.g. the atmosphere). Pollution leading to global warming and acid rain is affected by the problem of making the polluter pay for the damage caused. The course explores ways in which solutions to the prisoners’ dilemma can be found to solve both local and international issues of pollution. The ways in which legislation and public opinion can be used to address these problems is rich territory for ToK – is a system of rules better than a programme that educates and informs the public?





                    7 Climate change and energy production

  If you don’t read the newspaper, you are uninformed; if you do read the newspaper, you are misinformed.

Mark Twain














Power plant emissions in America

1.This topic addresses the way in which science can sometimes not be 100 per cent certain about particular issues, especially ones as complex as climate change. Is there a correlation between temperature rise and carbon dioxide emissions, or is the evidence eflectively circumstantial?

2.To what extent do politicians and environmentalists take advantage of the lack of consensus on the issue and use this to their own advantage?

3.Are there parallels between the influence of religious communities in the past and the influence of the political community today on the science of climate change and how it is interpreted?

4.The choice of energy sources is controversial and complex: how can we distinguish between scientific and pseudoscientific claims when making choices?

5.Regardless of the lack of hard scientific certainty regarding the evidence, should we nevertheless take preventive measures to avoid potential future catastrophe?

6.With the degree of uncertainty relating to the extent and eflect of climate change, how can we best decide what to do, given

our understanding is based on often provisional or incomplete knowledge?


Some of the scientists, I believe, haven’t they been changing their opinion a little bit on global warming? There’s a lot of diflering opinions and before we react I think it’s best to have the full accounting, full understanding of what’s taking place.

George W Bush

Bias and spin

Global warming challenges views of certainty within the sciences. In the popular perception, global warming is having a negative impact on the world. There is, moreover, some confusion in the public mind between global warming and the greenhouse effect. The greenhouse effect is a natural process, without which there would be no life on Earth. There is, however, an enhanced or accelerated greenhouse effect which is implicated in global warming.


The enhanced greenhouse effect is largely due to human (anthropogenic) forces, although feedback mechanisms may trigger some natural forces, too.


Lobby groups and politicians may take views which suit their own economic and political ends – it is possible to hide other agendas behind the uncertainties around global warming (causes, consequences and potential solutions). In the USA, the strength of the oil companies during the Bush administration was seen by many as an example of an economically powerful group, and the politicians it supported, choosing a stance which was not in the long-term environmental, social or economic interest of the world. However, there were short-term benefits for both the oil companies and the politicians they supported.


Case study

Humans are leaving a massive footprint on the planet. Is this damage reversible?

The warnings about global warming have been extremely clear for a long time. We are facing a global climate crisis. It is deepening. We are entering a period of consequences.

Al Gore

                                   8 Human systems and resource use

This topic examines the intrinsic values (e.g. aesthetic and indirect) of nature as opposed to the values that are measured on economic grounds. This exemplifies the problem of trying to give a value to (i.e. quantifying) factors that are qualitative in nature. The value of the systems approach is especially highlighted in this part of the course.

The concepts of resource and carrying capacity are given a fresh look by using the systems approach, and models of ecological footprint and natural capital/income bring a new moral and political perspective to these subjects.The term natural capital came from ecologically minded economists, and brings with it a value system which implies that resources must have an economic value.




The baggage such terms come with encourages a particular view of the world. Terms can therefore influence the way we see the world. The term ecological footprint considers the environmental threat of a growing population, whereas carrying capacity makes us see the same issues in terms of the maximum number a population can reach sustainably.

Does such use of language aflect our understanding of concepts and environmental issues? It has been claimed that historians cannot be unbiased – could the same be said of environmental scientists when making knowledge claims? Human carrying capacity of the environment is diflcult to quantify and contains elements of subjective judgement.

This topic also oflers the opportunity to discuss the models and indicators that are employed to quantify human population dynamics: to what extent are the methods of the human sciences ‘scientific’? Do they ofler a quantitative assessment or a qualitative one?

Your descendants shall gather your fruits.


Population and resources

  • Population growth is going to use up the world’s resources.

  • Population growth will stimulate the development of new resources.

Both of these views are valid. Which one do you believe? It may depend on the time scale and spatial scale that you use. On a small time scale, there is evidence that population growth can lead to famine (e.g. in Ethiopia in 1984). However, during the 1984 famine, Ethiopia was exporting crops – not everyone had access to food and that is why there was famine. In addition, there was long-term drought. Human


populations have so far managed to survive on Earth, despite massive increases in the size of the human population.

However, population decline in Easter Island suggests that environmental mismanagement could lead to population crashes. Maybe we just haven’t been there on a global scale yet.

Case study

Population crash on Easter Island














Easter Island is famous for its statues of heads.

Easter Island was discovered by Europeans in 1722. The island is about 117 km2 and situated about 3700 km west of the Chilean coast. It is one of the most remote inhabited islands in the world. It was colonized by Polynesian people in AD 700 and the population peaked at 12 000 around 1600. The population is now about 4000.

Pre-1600, the islanders had a diet of birds and fish. But after about 1600, palm forests disappeared and also the supply of birds and fish ran out. There was social disintegration, starvation, hardship, and conflict (Malthusian crisis) in the post-1600 period.


The cause of the crisis appears to be total deforestation related to the cult of statue building. Trees were used to move the statues. Removal of the trees led to soil erosion, landslides, crop failures and famine. Thus, it appears to have been a human-made ecological disaster – namely overuse of resources.

However, by 1722 when the island was discovered, there was no sign of such a crisis. The islanders had reorganized their society to regulate their use of resources and control their distribution (Boserup: ‘necessity is the mother of invention’). But between 1722 and 1822, the arrival of Europeans led to the spread of disease and the death rate increased. In 1862, slave traders from Peru took 1500 slaves (a third of the population).


Only 15 returned home, and these brought smallpox with them. By 1877, the population was down to just 111. The population has now risen to over 4000 largely as a result of migration. Easter Island is now struggling to cope with a new distinction: it was recently named by UNESCO as a World Heritage Site and the pressure caused by tourism is having a negative impact on resource availability for some of the islanders.


  • Is Easter Island an example of a Malthusian population– resource disaster?

  • Is it an example of human ingenuity coping with a crisis?

  • What do you think?


There is a suflciency in the world for man’s need but not for man’s greed.

Mohandas K Gandhi


Moral issues

In 1997, an article on agricultural issues in the UK appeared. In a section entitled ‘BSE (blame someone else)’, the author wrote:

Why did it aflect the UK? A number of theories can be put forward.

< >It could be just bad luck.Few places outside the UK sufler from scrapie and also raise large numbers of cattle.Cattle carcases in the UK are burned at relatively low temperatures.Cattle in the UK derive up to 5 per cent of their cattle ration from meat and bone meal.

Consumers are worried about whether eating beef is safe. Steak almost certainly is. Muscle (meat) does not seem to carry BSE. The danger lies in eating pies, burgers and sausages which might have bits of infectious brain or spinal cord in them.

The publishers of this article received an irate letter from the National Farmers Union (NFU) in which it was claimed that there was no scientific evidence to suggest that BSE was due to farming practices in the UK, that the author was scaremongering and just trying to be sensationalist in order to get noticed.

As a result, the publishers sent out a letter highlighting the views of the NFU. Should they have done so? Should the author ofler an apology? Should the author and publisher publish what they believe  to be right? One of the issues here is, where do you draw the line? If an oil company were to say there

is no link between burning fossil fuels and global warming, would you believe them? What interests does the NFU have? What interests do the author and the publisher have?

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