AP Environmental Science - 4.2 Soil Formation and Erosion

Which of the following is FALSE?

• Soil is composed of only geologic materials.  Organic matter is not considered to be part of the soil.

• Soil provides many important services like anchoring plants, cleaning water, cycling nutrients, and providing habitat.

• Weathering is the breakdown of parent material and can be physical, chemical or biological in nature.  Weathering is the start of soil formation.

• Erosion transports weathered rocks and soil from one place and deposits them in another.

Which of the following is FALSE?

• Parent material, topography and climate all play a role in soil formation.  Steeper ground will erode more easily and warmer climates will breakdown organic material faster.

• The A-horizon is also known as topsoil and contains a lot of organic matter, whereas the C-horizon is the closest to the parent material and contains little organic matter.

• Soil can be degraded by erosion and compaction, both of which can limit the ability of the soil to support plant growth. 

• The O-horizon is the first to form and is the very bottom soil horizon.