Exploring Soil Layers

Exploring Soil Layers

Read each question carefully and answer to the best of your ability. Refer to the diagram of soil layers when needed.

Observe the diagram below showing the different soil horizons.

1. Which soil horizon is typically found at the very top and is rich in organic matter?

2. Which horizon is often called the 'subsoil' and contains an accumulation of clay and minerals leached from above?

3. The uppermost layer of soil, rich in decayed organic matter, is called the   horizon.

4. The solid rock layer beneath all the soil horizons is known as the  .

5. Water carrying dissolved minerals downwards through the soil is called  .

6. The A horizon is primarily made up of weathered parent material.

7. Humus is a dark, organic material that forms in soil when plant and animal matter decays.

8. Describe the main characteristic of the O horizon. What is its importance to the soil?

9. Explain how the C horizon differs from the R horizon.

Use the words below to complete the sentences.

10. The A horizon is also commonly known as  , and it is crucial for plant growth.

11. The B horizon is often referred to as  .

12. The R horizon is also known as  .