1. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu How to Use This Presentation To View the presentation as a slideshow with effects select “View” on the menu bar and click on “Slide Show.” To advance through the presentation, click the right-arrow key or the space bar. From the resources slide, click on any resource to see a presentation for that resource. From the Chapter menu screen click on any lesson to go directly to that lesson’s presentation. You may exit the slide show at any time by pressing the Esc key.

2. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter Presentation Transparencies Image and Math Focus Bank Bellringers Standardized Test Prep CNN Videos Visual Concepts Resources

3. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Weathering and Soil Formation Section 1 Weathering Section 2 Rates of Weathering Section 3 From Bedrock to Soil Section 4 Soil Conservation Chapter 10 Table of Contents

4. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Bellringer Think about how potholes form in paved roads. Write a few sentences that describe how water contributes to the formation of potholes. Illustrate how cycles of freezing and thawing help cause potholes to grow. Record your response in your science journal. Chapter 10

5. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10 Describe how ice, water, wind, gravity, plants, and animals cause mechanical weathering. Describe how water, acids, and air cause chemical weathering of rocks. Objectives

6. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10 Mechanical Weathering Ice The alternate freezing and thawing of soil and rock, called frost action, is a form of mechanical weathering. Abrasion Abrasion is the grinding and wearing away of rock surfaces through the mechanical action of other rock or sand particles. Wind, Water, and Gravity Wind, water, and gravity carry rocks, causing them to abrade against one another.

7. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10 Ice Wedging Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

8. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10 Mechanical Weathering, continued Plants As a plant grows, the force of the expanding root becomes so strong that it can break a rock apart. Animals Almost any animal that burrows causes mechanical weathering by mixing and digging through soil and rock particles.

9. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10 Animals and Mechanical Weathering Animals that burrow in the ground break up soil and loosen rocks to be exposed to further weathering.

10. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10 Chemical Weathering Water Even hard rock, such as granite, can be broken down by water. The next slide shows how this can happen. Acid Precipitation The high level of acidity in acid precipitation can cause very rapid weathering of rock. Acids in Groundwater When acidic groundwater comes into contact with limestone, the limestone is dissolved and forms karst features.

11. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10

12. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10 Chemical Weathering, continued Acids in Living Things Some living things, such as lichens, produce acids that can slowly break down rocks. Air Oxygen in the air causes oxidation. Oxidation is the chemical reaction in which an element, such as iron, combines with oxygen to form an oxide.

13. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 1 Weathering Chapter 10 Oxidation Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

14. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Rates of Weathering Bellringer Imagine that you are in a sand castle-building competition at the beach. Come up with ways to protect your castle against the weathering effects of the wind and waves. Record your response in your science journal. Chapter 10

15. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Rates of Weathering Chapter 10 Explain how the composition of rock affects the rate of weathering. Describe how a rock’s total surface area affects the rate at which the rock weathers. Describe how differences in elevation and climate affect the rate of weathering. Objectives

16. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Rates of Weathering Chapter 10 Differential Weathering What Is Differential Weathering? Differential weathering is a process by which softer, less weather resistant rock wear away and leave harder, more weather resistant rock. The image below is an example of differential weathering.

17. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Rates of Weathering Chapter 10 The Shape of Rocks Surface Area The more surface area of a rock that is exposed to weathering, the faster the rock will be worn down. Increasing the Rate of Weathering If a large rock is broken down into smaller fragments, weathering of the rock happens much more quickly.

18. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Rates of Weathering Chapter 10

19. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Rates of Weathering Chapter 10 Weathering and Climate What Is Climate? Climate is the average weather condition in an area over a long period of time. Temperature and Water The rate of chemical weathering happens faster in warm, humid climates. Water also increases the rate of mechanical weathering.

20. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 2 Rates of Weathering Chapter 10 Weathering and Elevation High Elevations Rocks at higher elevations, as on a mountain, are exposed to more wind, rain, and ice than rocks at lower elevations. Steep Slopes The steepness of mountain slopes increases the effects of mechanical and chemical weathering. Steep slopes cause water and sediments to quickly run down the side of the mountain.

21. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Bellringer Answer the following questions: Has there always been soil on Earth? What makes soil valuable to humans? Write your answers in your science journal. Chapter 10

22. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Chapter 10 Describe the source of soil. Explain how the different properties of soil affect plant growth. Describe how various climates affect soil. Objectives

23. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Chapter 10 The Source of Soil What Is Soil? Soil is a loose mixture of small mineral fragments, organic material, water, and air that can support the growth of vegetation. Residual and Transported Soil Soil that remains above its parent rock is called residual soil. Soil that is blown or washed away from its parent rock is called transported soil.

24. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Chapter 10 Residual and Transported Soil Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

25. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Chapter 10 Soil Properties Soil Texture and Soil Structure Soil texture is the soil quality that is based on the proportions of soil particles. Soil structure is the arrangement of soil particles.

26. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Chapter 10 Section 3 From Bedrock to Soil

27. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Chapter 10 Soil Properties, continued Soil Fertility A soil’s ability to hold nutrients and to supply nutrients to a plant is described as soil fertility. Soil Horizons Because of the way soil forms, soil often ends up in a series of layers called horizons. Soil pH Soils can be acidic or basic. The pH scale is used to measure how acidic or basic a soil is.

28. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Chapter 10 Leaching Click below to watch the Visual Concept. You may stop the video at any time by pressing the Esc key. Visual Concept

29. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Chapter 10 Soil and Climate Tropical Rain Forest Climates The warm soil in tropical rain forest climates allows dead plants and animals to decay easily. This provides rich humus to the soil. Desert Climates The lack of rain in desert climates leads to low rates of chemical and mechanical weathering.

30. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 3 From Bedrock to Soil Chapter 10 Soil and Climate, continued Temperate Forest and Grassland Climates Temperate forest and grassland climates get enough rain to cause a high level of chemical weathering, but not too much that nutrients are leached out. Arctic Climates In arctic climates, as in desert climates, chemical weathering occurs very slowly. Low temperatures slow the formation of humus.

31. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Soil Conservation Bellringer Franklin D. Roosevelt once said: “The nation that destroys its soil destroys itself.” What do you think this quote means? Record your response in your science journal. Chapter 10

32. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Soil Conservation Chapter 10 Describe three important benefits that soil provides. Describe four methods of preventing soil damage and loss. Objectives

33. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Soil Conservation Chapter 10 The Importance of Soil Nutrients Soil provides minerals and other nutrients for plants. All animals get their energy from plants. Housing Soil provides a place for animals to live. Water Storage Without soil to hold water, plants would not get the moisture or the nutrients they need.

34. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Soil Conservation Chapter 10 Soil Damage and Loss Overuse Overused soil can lose its nutrients and become infertile. Soil Erosion When soil is left unprotected, it can be exposed to erosion. Erosion is the process by which wind, water, or gravity transport soil and sediment from one location to another.

35. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Soil Conservation Chapter 10 Contour Plowing and Terracing Contour Plowing In contour plowing, the rows of soil act as a series of dams to prevent water from eroding topsoil away. Terracing If hills are steep, farmers can using terracing. Terracing changes one steep field into a series of smaller, flatter fields.

36. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Section 4 Soil Conservation Chapter 10 Cover Crop and Crop Rotation Cover Crops Cover crops are crops that are planted between harvests to replace certain nutrients and prevent erosion. Cover crops prevent erosion by providing cover from wind and rain. Crop Rotation Farmers can rotate crops that use different nutrients so that nutrients in the soil have time to become replenished.

37. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Weathering and Soil Formation Concept Map Use the terms below to complete the concept map on the next slide. Chapter 10 parent rock chemical weathering mechanical weathering rock ice wedging oxidation soil

38. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Weathering and Soil Formation Chapter 10

39. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Weathering and Soil Formation Chapter 10

40. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu End of Chapter 10 Show

41. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Reading Read each of the passages. Then, answer the questions that follow each passage. Chapter 10 Standardized Test Preparation

42. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Passage 1 Earthworms are very important for forming soil. As they search for food by digging tunnels in the soil, they expose rocks and minerals to the effects of weathering. Over time, this process makes new soil. And as the worms dig tunnels, they mix the soil, which allows air and water and smaller organisms to move deeper into the soil. Worms have huge appetites. They eat organic matter and other materials in the soil. One earthworm can eat an amount equal to about half its body weight each day! Continued on the next slide Chapter 10 Standardized Test Preparation

43. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Passage 1, continued Eating all of that food means that earthworms leave behind a lot of waste. Earthworm wastes, called castings, are very high in nutrients and make excellent natural fertilizer. Castings enrich the soil and enhance plant growth. Chapter 10 Standardized Test Preparation

44. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. In the passage, what does enhance mean? A to weaken B to improve C to smooth out D to decrease Chapter 10 Standardized Test Preparation

45. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. In the passage, what does enhance mean? A to weaken B to improve C to smooth out D to decrease Chapter 10 Standardized Test Preparation

46. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. According to the passage, the earthworms F eat organic matter and other materials in soil. G do not have much of an appetite. H love to eat castings. I cannot digest organic matter in soil. Chapter 10 Standardized Test Preparation

47. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. According to the passage, the earthworms F eat organic matter and other materials in soil. G do not have much of an appetite. H love to eat castings. I cannot digest organic matter in soil. Chapter 10 Standardized Test Preparation

48. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. Which of the following statements is a fact according to the passage? A Earthworms are not important for forming soil. B Earthworms only eat organic matter in the soil. C An earthworm can eat an amount that equals half its body weight each day. D Earthworms eat little food but leave behind a lot of waste. Chapter 10 Standardized Test Preparation

49. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. Which of the following statements is a fact according to the passage? A Earthworms are not important for forming soil. B Earthworms only eat organic matter in the soil. C An earthworm can eat an amount that equals half its body weight each day. D Earthworms eat little food but leave behind a lot of waste. Chapter 10 Standardized Test Preparation

50. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Passage 2 Worms are not the only living things that help create soil. Plants also play a part in the weathering process. As the roots of plants grow and seek out water and nutrients, they help break large rock fragments into smaller ones. Have you ever seen a plant growing in a crack in the sidewalk? As the plant grows, its roots spread into tiny cracks in the sidewalk. These roots apply pressure to the cracks, and over time, the cracks get bigger. As the plants make the cracks bigger, ice wedging can occur more readily. Continued on the next slide Chapter 10 Standardized Test Preparation

51. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Passage 2, continued As the cracks expand, more water runs into them. When the water freezes, it expands and presses against the walls of the crack, which makes the crack even larger. Over time, the weathering caused by water, plants, and worms helps break down rock to form soil. Chapter 10 Standardized Test Preparation

52. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. How do plants make it easier for ice wedging to occur? A Plant roots block the cracks and don’t allow water to enter. B Plant roots provide moisture to cracks. C Plant roots make the cracks larger, which allows more water to enter the cracks. D Plants absorb excess water from cracks. Chapter 10 Standardized Test Preparation

53. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. How do plants make it easier for ice wedging to occur? A Plant roots block the cracks and don’t allow water to enter. B Plant roots provide moisture to cracks. C Plant roots make the cracks larger, which allows more water to enter the cracks. D Plants absorb excess water from cracks. Chapter 10 Standardized Test Preparation

54. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. For ice wedging to occur, F water in cracks must freeze. G plant roots must widen cracks. H acid is needed. I water is not needed. Chapter 10 Standardized Test Preparation

55. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. For ice wedging to occur, F water in cracks must freeze. G plant roots must widen cracks. H acid is needed. I water is not needed. Chapter 10 Standardized Test Preparation

56. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. Which of the following statements is a fact according to the passage? A Plant roots can strangle earthworms. B Earthworms eat plant roots. C Plant roots cannot crack sidewalks. D Plant roots break large rock fragments into smaller ones. Chapter 10 Standardized Test Preparation

57. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. Which of the following statements is a fact according to the passage? A Plant roots can strangle earthworms. B Earthworms eat plant roots. C Plant roots cannot crack sidewalks. D Plant roots break large rock fragments into smaller ones. Chapter 10 Standardized Test Preparation

58. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Interpreting Graphics The graph below shows the average yearly rainfall in five locations. Use the graph below to answer the questions that follow. Chapter 10 Standardized Test Preparation

59. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. Which location has the most average yearly rainfall? A 1 B 2 C 4 D 5 Chapter 10 Standardized Test Preparation

60. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. Which location has the most average yearly rainfall? A 1 B 2 C 4 D 5 Chapter 10 Standardized Test Preparation

61. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. At which location would you expect to find the most chemical weathering? F 1 G 3 H 4 I 5 Chapter 10 Standardized Test Preparation

62. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. At which location would you expect to find the most chemical weathering? F 1 G 3 H 4 I 5 Chapter 10 Standardized Test Preparation

63. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. At which location would you expect to find the least amount of chemical weathering? A 2 B 3 C 4 D 5 Chapter 10 Standardized Test Preparation

64. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. At which location would you expect to find the least amount of chemical weathering? A 2 B 3 C 4 D 5 Chapter 10 Standardized Test Preparation

65. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Math Read each question, and choose the best answer. Chapter 10 Standardized Test Preparation

66. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. If an earthworm that weighs 1.5 g eats an amount equal to half its body weight in a day, how much does the earthworm eat in 1 week? A 10.5 g B 7 g C 5.25 g D 1.5 g Chapter 10 Standardized Test Preparation

67. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 1. If an earthworm that weighs 1.5 g eats an amount equal to half its body weight in a day, how much does the earthworm eat in 1 week? A 10.5 g B 7 g C 5.25 g D 1.5 g Chapter 10 Standardized Test Preparation

68. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. Calculate the surface area of a cube that measures 3 cm by 3 cm. F 9 cm G 9 cm 2 H 54cm I 54 cm 2 Chapter 10 Standardized Test Preparation

69. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 2. Calculate the surface area of a cube that measures 3 cm by 3 cm. F 9 cm G 9 cm 2 H 54cm I 54 cm 2 Chapter 10 Standardized Test Preparation

70. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. If a mountain peak weathers away 2 cm every 6 years, how many years will the mountain peak take to weather away 1 m? A 8 years B 12 years C 180 years D 300 years Chapter 10 Standardized Test Preparation

71. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 3. If a mountain peak weathers away 2 cm every 6 years, how many years will the mountain peak take to weather away 1 m? A 8 years B 12 years C 180 years D 300 years Chapter 10 Standardized Test Preparation

72. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 4. The rock ledge that lies under a waterfall erodes about 3 cm each year. How much of the rock will erode over a period of 18 months? F 4.5 cm G 6 cm H 21 cm I 54 cm Chapter 10 Standardized Test Preparation

73. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 4. The rock ledge that lies under a waterfall erodes about 3 cm each year. How much of the rock will erode over a period of 18 months? F 4.5 cm G 6 cm H 21 cm I 54 cm Chapter 10 Standardized Test Preparation

74. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 5. A garden shop charges $0.30 for each ground-cover seedling. How many seedlings can you buy for $6.00? A 5 seedlings B 18 seedlings C 20 seedlings D 200 seedlings Chapter 10 Standardized Test Preparation

75. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu 5. A garden shop charges $0.30 for each ground-cover seedling. How many seedlings can you buy for $6.00? A 5 seedlings B 18 seedlings C 20 seedlings D 200 seedlings Chapter 10 Standardized Test Preparation

76. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Weathering and Soil Formation Chapter 10

77. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Weathering and Soil Formation Chapter 10

78. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu Weathering and Soil Formation Chapter 10

79. Copyright © by Holt, Rinehart and Winston. All rights reserved. ResourcesChapter menu CNN Videos Homemade Dirt Homemade Dirt Prairie Restoration Prairie Restoration Chapter 10