Human Impact on the Lithosphere: Energy Sources and Soil Erosion

1. Unit 3 Human Impact on the Lithosphere

2. Bell Work: On a sheet of notebook paper, draw the table below and complete by listing 3 advantages or benefits and 3 disadvantages or limitations for each of the 3 energy sources.

3. Bell Work: Greed Town has a population of 12,000. 8,000 live in FilthyRich neighborhood and uses 5 units of energy and 4,000 live in Envy apartments and use 2 units of energy. If a single wind turbine provides 1 unit of energy, how many wind turbines are needed to power the neighborhood and apartments?

4. Bell Work (on a ½ sheet of paper) Operational Definition Characteristics (words or picture) Choose 1 Word: Overburden, Exfoliation, Deforestation, Urbanization, Nuclear Fission, Biodiversity, Carrying Capacity, Density-dependent limiting factor Christina.augustine@dpsnc.net Examples Non Example

5. City Building Project Concept Sketch: The concept sketch due at the end of class must include: The name of your city Number of people in your city The total amount of energy NEEDED for all stores, apartments and neighborhoods Which energy producers will provide all of the energy that your city needs? What will your visual representation be (poster, diorama, etc.)

6. Bell Work: Complete the “Soildoku” Put all assignments due at the top of your desk for collection

7. Exit Ticket: Why is dirt considered “living”? How does a fungus help make the dirt in a forest?

8. Bell Work: Write about the following on a separate sheet of notebook paper: In “Dirt! The movie”, why were they removing the mountaintops? What resource were they after? What happened to the soil?

9. Dirt Why is dirt important? • It covers most land surfaces. • All life depends on about a dozen elements that come from Earth’s crust. • Plants absorb nutrients in the soil to live, and we eat plants.

10. What factors interact to form Dirt? • Parent material: the source of minerals in dirt • Time: over time more rock is weathered and particles get smaller • Climate: affects the amount of nutrients in the dirt

11. What factors interact to form Dirt? • Organisms: break down dirt • Slope: steeper slopes = more water runs off and washes nutrients away = less for plant growth

12. Exit Ticket: Why is the root system of a plant important for soil? What are the benefits of a green roof?

13. Homework: Due Friday March 13 On a separate sheet of notebook paper, write 1 paragraph for EACH of the following: “Dirt! The movie” ended with examples of how working with the soil of the Earth can change someone’s life. Describe one of these examples. Describe the possible applications of microbial fuel cells that were described in the movie. Explain the relationship between dirt, desertification, and political conflict.

14. Bell Work: Why is dirt important? Describe 3 things that make dirt important in your life. Unit 3 Summary: page 65 Notes: page 67

15. Weathering & Erosion Natural forces that shape Earth’s surface

16. How weathering forces shaped Hawaii’s shoreline http://www.pbs.org/wnet/nature/lessons/breaking-it-down/video-segments/1702/

17. What is Erosion?

18. Soil Erosion • Human activity disturbs Earth’s surface leading to loss of fertile topsoil. • Rain erodes away soil - a drop of rain blasts soil particles off the surface. • Water flow in streams and rivers moves dislodged particles of soil. • Sheet erosion occurs when thin sheets of water move the soil

19. Soil Erosion from rivers & streams • Water flows in sheets and then forms tiny streams called rills • Rills become trenches called gullies • Gullies move down slopes into streams • Soil particles are picked up and moved as sediments • What can happen to sediments (recall the rock cycle!)?

20. Rates of erosion • Human activities that remove natural plant life accelerate erosion of soil. • Depends on the climate, slope of the land and the type of vegetation. Scientists measure the rates of erosion by how much sediment is in rivers.

21. Weathering & Erosion Climate factors that affect weathering: • Precipitation (rainfall) • Temperature Wet, warm climates will lead to more chemical weathering Cool, dry climates will lead to more physical weathering

22. Bell Work What are the climate factors that affect weathering? How is the type of weathering in wet, warm climates different from the type of weathering in dry, cool climates? Why is it different?

23. Erosion due to gravity: The force of gravity tends to pull materials downslope • Mass Movement: the downslope movement of loose sediments and weathered rock resulting from the force of gravity • Creep: The slow, steady, downhill flow of loose, weathered Earth due to gravity

24. Wind erosion: occurs most in areas with little rainfall & high temperatures • Abrasion: Erosion that occurs when particles like sand rub against the surface of other materials • Deflation: The lowering of land surface that results from the wind’s removal of surface particles

25. Glaciers: Scrape and gouge out large sections of Earth’s surface as they move and deposit sediment in new locations

26. Weathering • The physical breakdown or chemical alteration of rocks to form soil or loose particles • The earth is changing constantly due to weathering • The 2 types of weathering are: mechanical (or physical) & chemical

27. Mechanical Weathering • Rocks get broken into smaller pieces, but their composition (what they are made of) does NOT change. Like tearing up a piece of paper • Breaking a rock down increases its surface area and the area of the rock exposed to mechanical and chemical weathering • The 3 mechanical weathering processes are: frost wedging, unloading & biological activity

28. Frost wedging • When water freezes, it expands • When water gets into cracks in rocks and then freezes, the water expands and breaks the rock

29. Frost wedging • Leads to cycles of freezing & thawing

30. Frost wedging • Happens where water freezes and thaws daily. Ex: mountains • In cold places roads will crack and form potholes • Talus: pile of rock that is wedged loose & falls

31. Unloading • The removal of a large weight of rocks or ice from a surface • Releases pressure on underlying rocks which expand upward and crack at the surface. • Great slabs of rock can be separated in a process called exfoliation • Exposes greater areas of rock to weathering

32. Unloading example: Half Dome, Yosemite, CA

33. Exfoliation example: Half Dome, Yosemite, CA

34. Exfoliation example: Devils Postpile, Yosemite, CA

35. Biological activity • Biological means living • Biological activity from plants and animals can cause mechanical weathering • Ex: tree roots pushing rocks apart as the tree grows

36. Chemical weathering • Changes the composition of the rock. Like burning a piece of paper. • Caused mainly by water • Water absorbs gases in the atmosphere, which chemically react with the minerals in rocks

37. Chemical weathering • Ex: Materials with iron – the iron turns to iron oxide, or rust, when exposed to water

38. Weathering leads to soil formation

39. The Rate of Weathering • Rate: how quickly something happens • Mechanical weathering exposes larger surface area on rocks which increases the effects of chemical weathering • Cracks in rocks lead to faster rates of weathering • High temperature and moisture increase the rate of weathering

48. Exit Ticket: • Where do you think frost wedging would be most likely to happen and why? • Where would the greatest amount of weathering occur and why: the tundra (northern Canada and Russia) or the tropical rain forest?

49. Bell Work: • Review for Unit 2 exam • Complete and turn in study guide for extra credit BEFORE exam.

50. When you have finished the exam: • Update Notebook • Complete any missing assignments from Unit 2 (today is the last day to turn in anything about earthquakes, volcanoes, plate tectonics or rocks) • On page 66, make a bubble map showing connections and definitions with these 9 words: Weathering Physical weathering Chemical weathering Frost wedging Biological activity Unloading Exfoliation Water Rust