Soil Horizons and Their Characteristics

Mr. Till introduces soil horizons, explaining their letter designations and characteristics. Key terms like organic matter, humus, and parent material are defined. A generalized soil profile model is presented, and its application to collected soil samples is discussed. Detailed descriptions of each horizon (O, A, E, B, C, R) are provided, followed by an animation illustrating soil horizon development. The video concludes with instructions for applying these concepts to real soil samples.

What is the purpose of assigning letter designations to soil horizons?

• To identify the age of the soil

• To describe typical characteristics of each horizon

• To determine the soil's pH level

• To measure the depth of the soil

Which of the following best describes organic matter in soil?

• Rocks and pebbles found in soil

• Particles that were once living or are currently living

• Minerals that have never been alive

• Water content in the soil

What is humus?

• A fully decomposed organic matter

• A type of mineral found in soil

• Partially decomposed organic matter

• A type of rock

What is the parent material of soil?

• The top layer of soil

• The original material from which soil develops

• The water content in soil

• The organic matter in soil

Which horizon is characterized by a high amount of organic matter?

• B Horizon

• C Horizon

• A Horizon

• O Horizon

What is the main characteristic of the A horizon?

• It is a mineral layer mixed with organic matter

• It is composed of solid rock

• It is the layer of accumulated particles

• It is the layer where particles are removed

What process occurs in the E horizon?

• Accumulation of organic matter

• Downward transport of particles

• Mixing of minerals and organic matter

• Formation of solid rock

Where do the particles removed from the E horizon accumulate?

• In the C horizon

• In the B horizon

• In the A horizon

• In the O horizon

What is the R horizon typically composed of?

• Partially decomposed parent material

• Mineral layer

• Organic matter

• Solid bedrock

What should you do when you identify a distinct layer in your soil sample?

• Remove it completely

• Mix it with other layers

• Apply a letter designation representing one of the horizons

• Ignore it and move to the next layer