Question 1

What is parent material?

Accepted Answer

Geological material that soil horizons form from

(underneath the soil; e.g., bedrock)

Question 2

What is weathering?

Accepted Answer

Breaking down parent material into smaller and smaller particles, forming soil

Question 3

What is deposition?

Accepted Answer

The process of introducing particles from other places into the soil

Question 4

What is a soil horizon?

Accepted Answer

A layer of soil with different properties and nutrients from the layers above and beneath it

Question 5

How does vegetation affect soil formation?

Accepted Answer

Vegetation helps hold soil in place, reducing erosion and helping formation

Plant roots also help break up parent material, forming soil

Question 6

How does soil form?

Accepted Answer

Over time, weathering breaks down parent material into smaller and smaller particles

Particles from other places might be introduced through deposition

Question 7

What is the O Horizon?

Accepted Answer

A layer of organic material at the very top of the soil

(consists of the remains of plants and animals)

Question 8

What is the A Horizon?

Accepted Answer

A layer of weathered and fertile soil, that has mostly mineral particles but also has organic matter

(below O Horizon or on top)

Question 9

What is the E Horizon?

Accepted Answer

A layer of leaching, where nutrients from upper horizons move to lower horizons

(E stands for eluviation/leaching; below A)

Question 10

What is the B Horizon?

Accepted Answer

A layer of subsoil where minerals such as iron and other nutrients accumulate

(below E or A)

Question 11

What is the C Horizon?

Accepted Answer

A layer of unconsolidated material above bedrock; not weathered enough to be considered soil

(usually too deep for plant roots; below B)

Question 12

What is bedrock (R Horizon)?

Accepted Answer

The solid rock that lies beneath the soil

(deepest layer; below C)

Question 13

What is the Dust Bowl?

Accepted Answer

A period of severe dust storms that caused major ecological and agricultural damage to the US in the 1930s

(poor agricultural practices led to soil erosion, exacerbating the event)

Question 14

How does soil affect water quality?

Accepted Answer

Soil and vegetation help filter water and remove pollutants, so if there is no soil or vegetation, water quality can be negatively impacted

Question 15

What causes soil erosion?

Accepted Answer

Soil erosion is caused by wind and water when there is no vegetation or plants to help hold the soil in place

Question 16

What is sediment transportation?

Accepted Answer

The movement of solid particles due to gravity, water, or some other force

Transportation of parent material can form soil

4.2 Soil Formation and Erosion, AP Environmental Science Flashcards