Chapter 27

39. Under ideal conditions it takes about _____________ to make 1 millimeter of soil.

A. 5 years B. 10 years C. 5 months D. 1 year E. 20 days Answer: D

37. Decomposers and detritivores break down organic material to help form topsoil. Which layer of soil contains the decomposers and detritivores that aid this process?

A. A horizon B. B horizon C. C horizon D. R horizon E. O horizon Answer: A

36. Which of the following layers of soil gets depleted during soil erosion?

A. A horizon B. B horizon C. C horizon D. R horizon E. none of these answers Answer: A

Refer to Infographic 27.4. Which soil layer contains the most decaying material and living organisms?

A. B horizon B. A horizon C. R horizon D. C horizon E. D horizon Answer: B

16. Which of the following does NOT explain how grazing can be beneficial to a grassland?

A. Clipping off the top part allows the sun to get to the new shoots. B. Hooves can break up soil, allowing water to penetrate. C. Breaking up soil with hooves allows new seeds to germinate. D. Defecation and urination from grazers adds phosphorus and nitrogen to the soil. E. Chewing a grass down to its roots helps it rejuvenate. Answer: E

Which statement is correct?

A. Grasslands are biomes. B. Grasslands receive enough rainfall to support grass and herbaceous plants. C. Grasslands do not get enough rainfall to support forests. D. Both B and C are correct. E. A, B, and C are correct. Answer: E

9. Which of the following statements are correct?

A. Grasslands are not found in Antarctica. B. Grasslands are found in every continent. C. Grasslands vary based on climate. D. Both A and C are correct. E. Both B and C are correct. Answer: D

52. What were some of the problems with the concept of rotational grazing?

A. It did not help to stop desertification. B. Savory felt it focused too heavily on limiting the number of animals allowed to graze. C. Savory felt it focused too heavily on the amount of time the animals were allowed to graze. D Both A and B are correct. E. None of these answers are correct. Answer: D

41. How does a prairie grass access water during a drought?

A. It has many shallow roots covering a large area to reach nearby rivers or streams. B. It has long deep roots allowing it to reach water supplies. C. It has long deep roots to hold the soil in place, thus producing a more porous soil. D. It stays shorter in a drought, thus not losing as much water through transpiration. E. Grasses are not adapted to drought, so they usually die. Answer: B

55. What is an outcome of planned grazing?

A. Keeping animals bunched for a set period of time ensures that all plants are grazed evenly, even weeds. B. It maximizes productivity. C. It helps keep plant biomass levels in an ideal range, which maximizes productivity. D. It makes ranching profitable again. E. All of these answers are correct. Answer: E

31. Which area seems to be at threat for major desertification?

A. New Mexico and western Texas B. New Mexico C. Mexico and southern Texas D. Arizona E. the Great Plains Answer: A

38. This layer contains rocks that are in the process of being broken down in order to produce new soil. Which horizon is this?

A. O horizon B. A horizon C. C horizon D. R horizon E. S horizon Answer: C

45. The long root systems of native prairie grasses allow them to access greater supplies of water and generally pass through which three soil horizons?

A. R, C, and B B. O,A, and C C. O,A, and B D.A, B, and C E. none of these answers Answer: C

7. Which statement is incorrect?

A. The Great Plains are a type of temperate grassland. B. The Great Plains lie between the Mississippi River and the Rocky Mountains. C. The Great Plains are also known as a rangeland. D. The Great Plains stretch from Texas to Canada. E. None of these answers are incorrect. Answer: C

25. The majority of domesticated animals being grazed on grasslands are___________.

A. cattle B. chickens C. pigs D. turkeys E. horses Answer: A

15. The most common cause of desertification of grasslands is_______________

A. climate change B. plowing too often C. depletion of aquifers D. overgrazing E. leaving them fallow Answer: D

8. Which types of grasslands are characterized by ultra thin layers of soil and very short growing seasons?

A. cold B. temperate C. savanna D. prairie E. rangeland Answer: A

29. Which of the following is a consequence of overgrazing in grasslands?

A. compaction of soil B. reduction in water penetration C. reduction in seed germination D. reduced seedling growth E. all of these answers Answer: E

Designing a process, such as grazing, so that it occurs in a way that is similar to how it happens in nature is known as ______________.

A. conservation B. biomimicry C. environmentalism D. ecology E. none of these answers Answer: B

50. The grassland protection mechanism that helps to reduce soil erosion, reduce water pollution, and increase wildlife habitat is known as ______________________.

A. conservation easement B. a conservation reserve program C. park status D. a shelterbelt E. none of these answers Answer: B

53. Which of the following is a way to protect our grasslands?

A. conservation reserve programs B. park status C. sustainable grazing D. both A and C E. all of these answers Answer: E

14. What is the main use of grasslands today by humans?

A. for recreational use B. growing food for humans C. as a food source for large grazing animals D. for energy production E. for housing construction Answer: C

26. What is the greatest threat facing grasslands today?

A. global climate change B. human-land use decisions C. overgrazing D. urbanization E. pollution Answer: C

28. Grassland that are MOST susceptible to desertification are found in ____________ areas.

A. humid B. arid C. cold D. boreal E. tropical Answer: B

24. As desertification of grasslands continues, smaller amounts of food will be available to feed humanity. What might be some of the consequences of the desertification of grasslands?

A. increased starvation B. movement of people from one area to another C. social unrest D. physical conflict between people of different cultures E. all of these answers Answer: E

43. The R horizon ___________________.

A. is solid, unbroken rock B. contains decaying and organic material C. is less fertile but higher in mineral content D. contains mostly surface litter E. is the rock that is in the process of being weathered or broken up Answer: A

17. One of the advantages of using land for grazing is __________________.

A. it takes less land per animal than feeding grain to livestock B. we are turning material we cannot eat into food that we can eat C. that plants are eaten faster than they can grow D. that the soil becomes compacted, making it harder for seeds to germinate E. All of these answers are advantages for using land for grazing. Answer: B

12. Grasslands provide which of the following ecosystem services?

A. nutrient cycling B. soil formation C. carbon sequestration D. wildlife habitats E. all of these answers Answer: E

22. Which of the following processes contribute to the process of desertification?

A. overgrazing by livestock B. global warming C. soil erosion D.A, B, and C E. none of these answers Answer: D

23. Soil erosion is often caused by _________________.

A. overgrazing by livestock B. soil compacting by large amounts of grazing herbivores C. grasses being grazed down to the growth area D. consumer demand for meat E. all of these answers Answer: E

The grassland that is found in cold climates is known as a ___________________

A. pampa B. steppe C. tall-grass prairie D. savanna E. northern mixed grass prairie Answer: B

1. All of the following are examples of grasslands except ____________________.

A. pampas B. steppes C. tall-grass prairies D. savannas E. none of these answers Answer: E

5. Which type of grasslands are also known as a savannas?

A. rangeland B. tropical C. cold D. temperate E. none of these answers Answer: B

49. Live stock ranchers often reach legal agreements with governments that permit them to use an area of land in a defined manner. These agreements are known as _____________________.

A. reserves B. shelter belts C. rotational grazing permits D. conservation easements E. none of these answers Answer: D

48. The animal farming technique known as __________________ allows animals to graze on one small section of a pasture for a few days before being moved to another section for grazing.

A. rotational grazing B. terracing C. planned grazing D. numerical limits grazing E. none of these answers Answer: A

42. Which two processes are essential to soil formation?

A. soil erosion and overgrazing B. decay of organic material and soil erosion C. decay of organic material and weathering of parent material D. weathering of parent material and overgrazing E. desertification and weathering of parent material Answer: C

54. What is rotational grazing an example of?

A. sustainable grazing B. shelterbelts C. a conservation reserve program D. a conservation easement E. none of these answers Answer: A

3. What factors lead to the maintenance of grassland ecosystems in a given area?

A. the amount of precipitation B. the presence of grazing animals C. periodic wildfires D.A, B, and C E. none of these answers Answer: D

4. Prairies are found in which of the following biome classifications?

A. tropical B. boreal C. temperate D. polar E. none of these answers Answer: C

30. Soil erosion in grasslands is a direct result of _____________.

A. urbanization and soil compaction B. soil compaction and energy production C. plant loss and urbanization D. plant loss and soil compaction E. plant loss and energy production Answer: D

44. Since the Dust Bowl of the 1930s, ______________.

A. we have become much more conscious of the value of our soil B. we have been able to devise viable methods of reclaiming grasslands lost to desertification C. we no longer overgraze or overplow our marginal agricultural areas D. the use of fertilizers and irrigation has increased the amount of arable land in the United States E. soil erosion is once again approaching Dust Bowl rates Answer: E

13. Which of the following crops was not originally derived from grasslands?

A. wheat B. rye C. barley D. rice E. millet Answer: D