Exploring Soil Layers
A Grade 7 science worksheet to help students understand the different layers of soil, their composition, and importance.
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Exploring Soil Layers
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Read each question carefully and answer to the best of your ability. Refer to the diagram of soil horizons to help you.
1. The uppermost layer of soil, rich in organic matter, is called the .
2. The layer often referred to as the 'subsoil' is the horizon.
3. Partially weathered parent material is found in the horizon.
4. The solid unweathered rock beneath the soil layers is known as the .
1. Which soil horizon is characterized by the accumulation of clay, iron, and aluminum?
O horizon
A horizon
B horizon
C horizon
2. Which of the following is NOT a component of healthy soil?
Minerals
Organic matter
Air
Pure water
1. The O horizon is primarily composed of bedrock.
True
False
2. The A horizon is also known as topsoil.
True
False
Match each soil horizon with its description.
1. O Horizon
a. Unweathered bedrock
2. A Horizon
b. Topsoil, rich in humus
3. B Horizon
c. Subsoil, accumulation of minerals
4. C Horizon
d. Organic matter, leaf litter
5. R Horizon
e. Partially weathered parent material
1. Explain why the topsoil (A horizon) is usually darker in color than the subsoil (B horizon).
2. Describe the importance of the O horizon for plant growth.