chemical weathering 294
conservation tillage 305
contour farming 303
crust 292
erosion 294
friable 296
horizon 297
humus 295
land 294
leaching 298 		lithosphere 292
litter 297
loam 296
mantle 292
mechanical weathering 293
parent material 294
plate tectonics 292
reduced tillage 305
soil 294
soil profile 297 		soil structure 296
soil texture 296
strip farming 304
terraces 304
waterways 304
weathering 293
windbreaks 304

On-line Flashcards
      What role does a prairie wetland have in reducing soil erosion? The story of wetlands in one of the most productive agricultural areas in the world is told in The Prairie Wetlands of Southwest Minnesota.
      You've heard it before but see it this time along with a great explanation of the process. Check out the Plate Tectonics animation to see and hear about the process and for an explanation of why different animals are found only in certain parts of the world.
Review Questions
  1. How are soil and land different?
  2. Name the five major components of soil.
  3. Describe the process of soil formation.
  4. Name five physical and chemical processes that break parent material into smaller pieces.
  5. In addition to fertility, what other characteristics determine the usefulness of soil?

  1. How does soil particle size affect texture and drainage?
  2. Describe a soil profile.
  3. Define erosion.
  4. Describe three soil conservation practices that help to reduce soil erosion.
  5. Besides cropland, what are other possible uses of soil?
Critical Thinking Questions
  1. Minimum tillage soil conservation often uses greater amounts of herbicides to control weeds. What do you think about this practice? Why?
  2. As populations grow, should we try to bring more land into food production, or should we use technology to aid in producing more food on the land we already have in production of food? What are the trade-offs?
  3. Given what you know about soil formation, how might you explain the presence of a thick A horizon in soils in the North American Midwest?
  1. Why should non-farmers be interested in soil conservation?
  2. Imagine that you are a scientist hired to consult on a project to evaluate land-use practices at the edge of a small city. The area in question has deep ravines and hills. What kinds of agricultural, commercial, and logging practices would you recommend in this area to help preserve the environment?
  3. Look at your own community. Can you see examples of improper land use (urban or rural)? What are the consequences of these land-use practices? What recommendations would you make to improve land use?