UNIT FOUR

1. UNIT FOUR Earth’s Resources and Human Impact (chapters 25, 26, and 27)

2. What is a typical day for you? • On a clean piece of paper (not in your notebook) make a list of everything you do on a typical day • Start from waking up and continue until you go back to bed at night • Keep your list handy for later

3. Words to live by … “Leave the world better than you found it, take no more than you need, try not to harm life or the environment, make amends if you do.” Paul Hawken The Ecology of Commerce

4. Natural Resources • Necessary for life • Provided by the Earth • Renewable or nonrenewable

5. Renewable Resources • Can be replaced within a reasonable amount of time • Living things (trees) • Fresh water • Fresh air • Soil • Solar Energy

6. Sustainable Yield • Refers to renewable resources • Occurs when replacement occurs at same rate as use

7. Nonrenewable Resources • Can only be replaced with processes that require hundreds of millions of years • Fossil fuels • Gems • Elements such as gold, silver, copper

8. Land Resources • Why important? • Growing food, feeding animals • Growing trees • Open space • Why protected by governments? • To prevent overuse • To protect endangered wildlife • To provide recreational / educational space

9. Soil, Part I • Review (chapter 7) • Broken rock pieces and decaying organic matter (humus) • Created through mechanical / chemical weathering, along with biological decay • Texture based on amounts of clay, silt, and sand

10. Soil, Part II • Topsoil requires hundreds of years to form • Easily lost through erosion (wind, water) • Desertification – creation of desert land through the loss of topsoil

11. Other Land Resources • Ore (mined at a profit) • Clay for bricks • Salt • Gypsum • Talc • Graphite

12. Obtaining Ore Resources • Mining • Surface (strip, open pit) • Underground (hard rock, shaft) • Problems • Polluted water • Dangerous chemicals • Gangue – waste rock that remains after ore is extracted

13. Air Resources • Oxygen • Only 21% of normal air • Origin believed to be volcanic eruptions and photosynthesis by early life forms • Also involved in the production of ozone • Ozone can be both good and bad (more on this when we study the atmosphere)

14. Air Pollution • Industrial Revolution • Pollutant – substance that negatively impacts survival, health, or normal function of living organisms • Sulfur oxides • Nitrogen oxides

15. Sources of Air Pollution • Natural • Forest fires • Volcanic eruptions • Human • Car exhaust • Factory exhaust

16. Movement of Air Pollution • Wind transport • Explains why New York state worries about pollution generated by factories in the Midwest • Wind can also dilute pollution • Precipitation removes some pollutants

17. Indoor Air Pollution • Toxic chemicals released by furniture, clothing, paints, … • Lack of fresh air circulation • Can make you sick • Silent pollutant – radon gas • Produces radioactive byproducts • Can cause lung cancer

18. Water Resources • 97% saltwater • 2.997% frozen fresh water • 0.003% accessible fresh water • Surface water • Ground water (in aquifers) • Water vapor

19. Why is water awesome? • Liquid for a full 100oC range • Stores heat well • Dissolves many other chemicals • Solid is less dense than liquid

20. Managing Water • Using dams to create reservoirs • Transporting water to dry places • Using wells to reach groundwater • Overuse leads to dry wells & sinkholes! • Desalination – removal of salt from seawater to create fresh water • Expensive & inefficient

21. http://www.youtube.com/watch?v=a_6M3CNZRkU • Activity • Go back to the list you made earlier • Identify the natural resources you used, and note if they were renewable or nonrenewable

22. Energy Resources • Traditional Sources • Wood • Field crops (hay, corn, straw) • Fecal material (dung) • Fossil fuels

23. Fossil Fuels • Nonrenewable • Creates lots of pollutants  • Formed from decomposing organics • Peat • Coal • Petroleum • Natural gas • Oil shale / tar sand (fracking)

24. More on Coal • Lignite • Forms from peat • Not very efficient (only 40% carbon) • Bituminous • More efficient (up to 85% carbon) • Anthracite • Most efficient (90 - 95% carbon) • Burns hottest and most cleanly

25. FRACKING • Inject liquid chemicals at high pressure • Helps remove natural gas from areas that were previously unreachable • Environmental concerns • Groundwater pollution • http://www.youtube.com/watch?v=LAxsTJd7VCA • http://www.youtube.com/watch?v=VY34PQUiwOQ

26. Alternative Energy Sources • Solar • Nonpolluting  • Passive • House designed with windows on south side • Active • House designed with solar collectors on roof • Photovoltaic cells • Solar energy changed into electricity for storage and later use

27. Water • Nonpolluting  • Hydroelectric plants • Running water makes electricity • Tidal plants • Uses ocean currents to make electricity

28. Wind • Wind farms • Requires steady, regular winds • Nonpolluting  • Renewable  • Dangerous to wildlife  • Can disrupt landscape beauty 

29. Nuclear • Very expensive • Waste is radioactive for MANY years • Efficient production of electricity • Major nuclear accidents • Three Mile Island, 1979, Pennsylvania • Chernobyl, 1986, Ukraine http://www.youtube.com/watch?v=3u_8frR0IpE • Fukushima Daiichi, 2012, Japan

30. Geothermal & Biomass • Geothermal – uses hot water and steam found naturally (near volcanoes) • Biomass – fuel based on living organisims • Wood, field crops, dung • Biogas (methane gas) • Ethanol / methanol

31. Conserving Energy • Why? • We’re using energy more quickly than the Earth can replace it • How? • Increase energy efficiency • Using energy in ways that maximize productivity and minimize waste

32. Increasing Energy Efficiency • Better designed technology • CFLs versus traditional bulbs • Hybrid cars • Cogeneration • Producing two usable forms of energy at the same time

33. Areas to Improve • Transportation • More and better public transportation • Better designed cities • Industry • Home • Solar panels • Insulation

34. Ultimate Goal • Sustainable Energy • Global management of resources in such a way as to meet today’s needs and still be able to provide energy for the future without environmental damage

35. Design an Energy Efficient House • In small groups, create a poster of a house that is energy efficient. • Include information on where your house is located and where North is located • Point out everything you have done to make the house energy efficient (inside and outside)

36. Human Interaction with Earth • http://www.youtube.com/watch?v=j7OHG7tHrNM • Populations grow quicker and quicker as the number of reproducing organisms increase • Exponential growth results in a population “explosion” which can overwhelm an area’s resources and ultimately lead to starvation

37. What keeps Populations in Check? • Carrying capacity – population size that a local environment can support • Density independent factors • Storms, floods, droughts, … • Density dependent factors • Disease, parasites, lack of food • Increased density increases danger

38. Negative Impact of Mining • Gangue (waste rock) • Disfigured landscapes • Surface / groundwater pollution • Dangerous chemicals

39. Surface Mining Control & Reclamation Act • Enacted in 1977 • Requires reclamation of mining sites • Reclamation restores mining area to its original state (plants, animals, topology) • Expensive & difficult to do

40. Negative Side of Agriculture • Monocultures • Growing only one crop at a time • Depletes the soil of same nutrients over and over • Requires more and more fertilizer for same yield • Pesticides / Herbicides • Pests and weeds develop a tolerance • Chemicals can be dangerous to animals and humans • Topsoil erosion • Deforestation

41. Landfills • Long-term storage of waste • Must be carefully designed to avoid contamination of ground and surface water • Decomposition produces methane gas, which can be collected and used to produce electricity • Bioremediation uses bacteria and other organisms to clean up toxic waste

42. More on Air Pollution • http://www.youtube.com/watch?v=Ksps_1Zwg5o • Smog – mixture of gases and particulate matter that make it difficult to breathe • Ozone – irritating gas that is particularly bad for humans and plants • Acid Precipitation – forms from the reaction between air pollution and rain

43. Climate Change • Greenhouse Effect – heat gets trapped in the atmosphere • “global warming” – increasing amounts of carbon dioxide correspond to increasing surface temperature on Earth • Ozone depletion – the “good” ozone in the atmosphere was reduced by the use of chemicals known as CFCs

44. What can be done? • Clean Air Act of 1990 • Set new standards and regulations • Power Plants • Required to diminish the amount of particulate matter released • Use “scrubbers” to clean exhaust before it is released into the air • Individuals • Conserve energy, carpool, …

45. More on Water Pollution • Point sources • Sewage plant or industrial site • Bacteria, viruses, toxic waste • Overly hot water • Nonpoint sources • Rainwater dissolves chemicals and carries them along as runoff • Fertilizer, pesticides, oil, gasoline

46. Problems with Water Pollution • Groundwater • Once polluted, very hard to clean up • Can contaminate drinking water • Ocean water • Can damage wildlife • Creates “dead zones” • http://www.youtube.com/watch?v=2VrrxMIiwgQ

47. How to Fix? • Clean Water Act • Established standards and regulations • Safe Drinking Water Act • Specifically focused on drinking water • Conservation • Think before you use • Fix leaky pipes and faucets • Take shorter showers

48. There has been a major industrial accident in Monroe. A cloud of irritating (but not lethal) gas has been released, and the local water supply has been contaminated with dangerous chemicals. • Create a list of rules and guidelines for Indian Trail citizens to follow until the mess is cleaned up in Monroe (10 -14 days). • Create a skit that can be used with little kids to help them understand what is going on without getting really scared.