Chapter 14 Resource Issues The Cultural Landscape An

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Why Are Resources Being Depleted? • Resource – A substance in the environment that is useful to people, is economically and technologically feasible to access, and is socially acceptable to use. – Resources include food, water, soil, plants, animals and minerals. • Energy resources – Around ½ of world’s energy is consumed in MDCs and ½ in LDCs – MDCs contain only around 1/3 of population of LDCs, so per capita consumption of energy is thus around three times higher in MDCs. – Three of Earth’s substances provide 5/6 of world’s energy • Coal—supplanted wood as leading energy source in late 1800 s • Petroleum—First pumped in 1859, but not an important resource until the diffusion of motor vehicles in 20 th century. • Natural Gas—used to heat homes © 2011 Pearson Education, Inc.

Why Are Resources Being Depleted? • Petroleum, Natural Gas, and Coal are fossil fuels. – A fossil fuel is the residue of plants and animals that were buried millions of years ago. When we burn these substances, we are releasing energy originally stored in plants and animals millions of years ago. • Two characteristics of fossil fuels cause great concern – The supply is finite—Once they’re consumed, they’re gone – Distributed unevenly around the globe • Earth’s resources are divided between those that are renewable and those that are not – Renewable energy—has essentially unlimited supply and is not depleted when used by people. Examples include hydroelectric, geothermal, fusion, wind, and solar energy. – Nonrenewable energy—forms so slowly that for practical purposes it cannot be renewed. Fossil fuels are examples. © 2011 Pearson Education, Inc.

US Energy Consumption—It has increased rapidly during the 1960 s, but since the early 1970 s it has increased at a much slower rate. The amount of energy derived from petroleum and natural gas increased rapidly during 1960 s, when use of coal stagnated. © 2011 Pearson Education, Inc.

Why Are Resources Being Depleted? • Control of World Petroleum – The US produced more petroleum than it consumed during the first half of the 20 th century. • Beginning in the 1950 s, the handful of large transnational companies then in control of int’l petroleum distribution determined that extracting domestic petroleum was more expensive than importing it from SW and Central Asia. – OPEC (Organization of Petroleum Exporting Countries) • At first, Western companies set oil prices and paid Asian governments only a small % of their oil profits. Several LDCs possessing substantial reserves created OPEC in 1960. • OPEC’s Arab members were angry at N. America and Europe for supporting Israel in 1973 war w/ Egypt, Jordan and Syria, so they imposed a boycott in which they refused to sell petroleum to nations who supported Israel. © 2011 Pearson Education, Inc.

Gas Lines 1973—When OPEC imposed the boycott, motorists in the US waited in long lines to purchase the limited supply of gas. Americans regarded Exxon’s posted price of 74 cents a gallon of regular gas to be outrageously high during this time. © 2011 Pearson Education, Inc.

US imported 57% of its crude oil in 2009, compared to only 31% in 1973. Since the 1980 s, domestic production has declined 40%, whereas consumption has increased 30%. The gap has been covered by a 60% increase in imports. © 2011 Pearson Education, Inc.

Global Warming—(top) Earth’s annual mean temperature has increased an average of 1 degree Celsius between 1880 and 2007. (bottom) Contributing to global warming has been a rapid increase in carbon dioxide emissions, primarily from fossil-fuel burning. © 2011 Pearson Education, Inc.

Regional-scale air pollution: Acid precipitation—A large % of trees in the forests of the Czech Republic have died. Emissions of sulfur dioxide and nitrogen oxides from factories built w/o pollution-control devices in the former Communist East Germany and Czechoslovakia caused this widespread death of trees. © 2011 Pearson Education, Inc.

Why Should Resources Be Conserved? • Sustainable Development – Development that meets the needs of the present w/o compromising the ability of future generations to meet their own needs. – Conservation—sustainable use and management of natural resources such as wildlife, water, and air to meet human needs. • Sustainability and Economic Growth – A rising level of economic development generates increased pollution, at least until a country reaches a GDP of about $5, 000, according the economists Alan Krueger. – In early stages of industrialization, pollution-control devices are unpopular b/c they make consumer goods more expensive. – Consequently, 20 th century environmental improvements by MDCs are likely to be offset by increased pollution of LDCs during 21 st century. © 2011 Pearson Education, Inc.

As a country’s per capita increases, discharge of sulfur dioxide increases, until GDP reaches about $5, 000. Then discharges tend to decrease as a country begins to spend money on pollution-control devices. © 2011 Pearson Education, Inc.

Why Should Resources be Conserved? • Biodiversity – Refers to the variety of species across Earth as a whole or in a specific place. It is an important development concept b/c it is a way of summing the total value of Earth’s resources available for human use. • A community containing a large number of species is species-rich • A community w/ a large population of many species is regarded as more diverse than a community w/ fewer species. – Sustainable development is promoted when the biodiversity of a particular place is protected © 2011 Pearson Education, Inc.