Weathering and Soil

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Weathering and Soil

• Test Review

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Question 1

• True or False After chemical weathering, the
  chemical make up of the rock is the same.
• False

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Question 2

• Which soil layer contains partially weathered
  rock?
• C Horizon

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Question 3

• What is the loose material on the Earths surface
  that contains humus?
• Soil

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Question 4

• Which soil layer is the best for growing plants?
• The A Horizon (Topsoil)

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Question 5

• What agent of mechanical weathering wears away
  rock by the grinding action of other rock
  particles?
• Abrasion

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Question 6

• How does ice wedging cause mechanical weathering
  of rocks?
• By freezing and thawing

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Question 7

• The growth of plant roots and animal activity is
  what type of weathering?
• Mechanical Weathering

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Question 8

• What kind of weathering causes the mineral
  composition of rocks to change?
• Chemical weathering

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Question 9

• A rock containing iron becomes soft and crumbly
  and reddish-brown in color. It has probably been
  weathered by what?
• Oxygen (oxidation)

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Question 10

• How does a hot and wet climate affect the rate of
  weathering?
• It makes it take place faster

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Question 11

• What are the most important factors in
  determining the weathering rate of rocks?
• Climate and mineral composition

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Question 12

• Why do permeable rocks weather easily?
• Because they are full of tiny connected air spaces

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Question 13

• How does soil formation begin?
• With the weathering of rock

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Question 14

• What is the mixture of rock particles, minerals,
  decayed organic material, water, and air called?
• Soil

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Question 15

• What is the decayed organic material in soil
  called?
• Humus

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Question 16

• Removing nutrients such as iron and copper from
  the ground is called what?
• Depletion

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Question 17

• Which soil particle is the largest?
• Gravel

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Question 18

• What soil particle is the smallest?
• Clay

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Question 19

• The type of soil called loam is made of what?
• Nearly equal amounts of sand, silt, and clay

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Question 20

• In which layer of soil is topsoil found?
• A Horizon

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Question 21

• What type of particles does the B Horizon
  contain?
• Clay, minerals, and a little humus

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Question 22

• What do living organisms do in the soil?
• Mix the soil and make humus

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Question 23

• What do decomposers do in soil?
• Break down and digest the remains of dead
  organisms

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Question 24

• Which organism does most of the work of mixing
  humus into the soil?
• Earthworms

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Question 25

• What can cause the loss of soil that is not
  protected by plant cover?
• Erosion by wind or water

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Question 26

• Plowing removed the grass from the Great Plains
  and exposed the soil. What effect did this have
  when a drought struck the Great Plains during the
  1930s?
• It helped to cause the Dust Bowl

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Question 27

• Using land to grow food crops is an example of
  what?
• Agriculture

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Question 28

• What is the solid layer of rock beneath the soil
  called?
• The Bedrock (R Horizon)

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Question 29

• What is another name for the B Horizon?
• Subsoil

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Question 30

• What type of weathering occurs when pollutants in
  the air mix with the water vapor in the air?
• Acid Precipitation