CHAPTER 22 HUMANS AND THE ENVIRONMENT

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1 CHAPTER 22 HUMANS AND THE ENVIRONMENT

2 Ecological footprint: analysis of people s use of food & natural resources & their production of wastes & pollution Human Resource Use -humans have exceeded Earth s capacity to repair itself - humans must learn to live sustainably

3 Acid rain destroys living things. - ph of 5.0 no longer supports fish - populations of frogs & other amphibians are becoming extinct because their young cannot properly develop in low ph water.

4 Some forests are dying Germany s Black Forest.

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6 -Burning of fossil fuels releases pollutants into the air -Nitrates, sulfates, & particulates

7 A possible fix: capture the polluting emissions. - expensive to install scrubbers. - polluter and the recipient of the pollution are far from each other and neither wants to pay the price Ex Canadians receiving U.S. industrial pollution

8 Destruction of the Ozone Layer - Bad ozone forms in lower atmosphere when exhaust emissions from cars and factories reach sunlight (smog) * is corrosive. * In humans: irritates/damages lungs, air passageways, eyes, suppresses the immune system, and aggravates heart disease.

9 - Good ozone (O 3 ) is the ozone layer in the Earth s outer atmosphere, which absorbs about 99% of all UV light before it reaches the Earth s surface. * A hole in the ozone layer over Antarctica opens for 6 weeks during late summer and early fall. * A hole has also opened over the Arctic.

10 * Ozone in these areas is an average of 50% thinner than 20 years ago. * Increased UV exposure has resulted in increased incidents of skin cancer, cataracts, and cancer of the retina.

11 - What is Destroying the Ozone Layer? * CFC s or chlorofluorocarbons (freon) - once considered inert - used as coolants in refrigerating equipment, aerosols, styrofoam. * CFC s stick to frozen water vapor over the poles changing O 3 (ozone) to O 2 (oxygen gas).

12 In the 1970 s CFC s were thought to be inert and in 1985 when the ozone holes were discovered, people became concerned. (FYI)

13 In the early 1990 s, the US and 92 other countries signed international agreements that banned CFC production. (FYI)

14 Burning fossil fuels increases the greenhouse effect

15 G W L A O R B M A I L N G The increase of gases in the air from fossil fuels being burned causes more of the sun s energy to be trapped in the atmosphere. FYI, no need to copy.

16 Using fossil fuels in industry and burning vegetation to clear land

17 Ecosystem Damage Pollution Society has always had a tendency to assume that the environment can absorb any amount of pollution.

18 Biological magnification: amounts of toxins increase significantly each trophic level in a food chain/web Ex: DDT pesticide - Outlawed in 1970 s Pollution

19 Lake Erie in the early 1970s, it was so polluted that few fish could survive. (FYI)

20 - little regulation on the manufacture, storage, and disposal of toxic and carcinogenic chemicals. ex: Switzerland 1986 In putting out a warehouse fire, 30 tons of mercury and pesticides ended up in the Rhine River and flowed into the North Sea; massive kills of aquatic life both plants and animals.

21 Alaska 1989 Exxon Valdez oil spill

22 Consuming Nonreplaceable Resources endangered: in danger of extinction extinction: death of every member of the species (Sorry to inform you that Jurassic Park isn t a true story.)

23 Tasmanian Wolf, 1936 Laughing owl, 1914 Bourbon crested sterling, 1950s

24 About 20% of the world s plants and animals will become extinct in the next 50 years.

25 Sustainable development: way of using natural resources w/o depleting & providing for human needs w/o causing long-term environmental harm - Quotas on how much fish you can catch Isn t this an ugly fish?

26 Conserving Biodiversity Conservation: wise management of natural resources - Try to protect entire ecosystems, not just individual species

27 Biodiversity -total of variety of all org s in biosphere Ecosystem diversity: includes variety of habitats, communities, & ecological processes in the living world Species diversity: # of different species in the biosphere - Over 1.5 million species in world

28 Habitat fragmentation: splitting of ecosystems into pieces habitat destruction = damming a river, draining swamps, logging, clearing land for agriculture or buildings

29 -Other plants & animals can even threaten species diversity Invasive species: introduced species that reproduces quickly because their new habitat lacks the pop. controls that they have back home

30 There are 3 kinds of nonrenewable resources which are being consumed at an alarming rate. TOPSOIL GROUNDWATER FOSSIL FUELS

31 Loss of topsoil made of organic matter (subsoil consists of inorganic particles and minerals) - the US has lost ¼ of its topsoil since 1950.

32 We have: 1) turned over soil to eliminate weeds 2) allowed overgrazing 3) practiced poor land management - ex: strip mining

33 To limit erosion: -plant vegetation on bare fields -no-till drill -build windbreaks - build irrigation ditches -contour plowing: plowing that follows the contour of a slope rather than going up & down -terracing: carving steps along a hillside

34 - One way we have lost soil is through mining in order to obtain minerals and fossil fuels Mining 3 types of mines: 1. Strip mines 2. Open pit mines 3. Shaft mines

35 strip mining: layers of Earth are removed to gain access to minerals - earthmoving equipment pushes soil away to expose ore

36 Ways to minimize environmental damage from strip mining: -treating & containing runoff -controlling emissions into the air -re-vegetating mined areas -replenishing topsoil that was removed

37 Open pit mining: dig a big pit -removes ore that starts near the surface & extends down for 100 s of meters Shaft mines: used to mine ore in veins -network of tunnels that follow the veins

38 -mining can be bad for the environment! -leaves scars on the land -waste materials pollute rivers & lakes -miners are required by law to replace any top soil that is removed during strip mining

39 Pollution and depletion of ground water 1) mostly trapped in porous rock reservoirs called AQUIFERS 2) Large amounts wasted watering lawns, washing cars, running fountains 3) if chemicals pollute it, there is no effective way to remove the pollution.

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41 Solving Environmental Problems A Reducing Pollution 1. Many successes in the 1990s: a Worldwide ban on CFC production. b In US, restricted or banned use of DDT, asbestos, and dioxin

42 c Also in the US: 1) Sulfur dioxide, carbon monoxide, and soot were cut by 30% in 10 years. 2) Sewage treatment plants removal of chemicals and bacteria has increased by 72% in the last 12 years. 3) EPA estimates businesses and private agencies are spending $100 billion per year on pollution control.

43 B Why Pollution is Profitable (FYI) 1. A weak link in our economy of supply and demand is that businesses do not pass on all of the indirect costs in making a product. Ex the cost of petroleum does not include all the money it would take to fix all the environmental problems created by extraction, shipment, refining, and use of petroleum products:

44 a reduced fish catches, b unusable lands, c air pollution resulting in damaged people (health), plants, buildings, d etc,etc,etc,etc. 2. All of these costs are passed on to future generations.

45 3. Pass Laws Forbidding Pollution --cars must have catalytic converters (breaks down toxic emissions)

46 4. Tax Things That Cause Pollution --increase cost of the product to hopefully reduce its use --cost can t be so high that it inhibits industrial growth --can happen in the form of pollution permits that were first auctioned in 1993.)

47 5. How to Solve Environmental Problems a 5 components to solving any environmental problem:

48 1) Assessment scientific analysis of what is happening; collecting data. Construct a model of the ecosystem and its response to your model. 2) Risk Analysis use scientific analysis and predict consequences of intervention; both good and bad.

49 3) Public Education --explain problem, list possible solutions, results, and costs. 4) Political Action --special interest groups, write letters, and vote. 5) Follow Through --watch to see if the environmental problem is being acted on.

50 6. What You Can Contribute a Recycle (table 22-2 p. 452)

51 HERE S AN IDEA, b Reduce personal use of resources, carpool, bicycle, walk, use public transportation, turn your heat down in the winter, and have a warmer home in the summer, turn off lights when you leave the room, etc, etc, etc.

52 c REUSE

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54 What Illinois could look like & it does in central Illinois