Soil Horizon Quiz: Test Your AP Environmental Science Knowledge

📚 Quick Study Guide

• 🌍 O Horizon (Organic Layer): This is the top layer, composed of organic matter like leaves, dead plants, and animal remains. It's crucial for nutrient cycling.
• 🌱 A Horizon (Topsoil): A mix of organic matter and minerals. It's dark in color and where plants grow. It's subject to leaching.
• ⛰️ E Horizon (Eluviation Layer): This is a zone of leaching, where minerals are transported downward. It's often light in color.
• 🧱 B Horizon (Subsoil): Accumulation of minerals leached from above. It's often rich in clay.
• 🪨 C Horizon (Parent Material): Partially altered bedrock. It's the transition zone between bedrock and soil.
• 🏞️ R Horizon (Bedrock): Unweathered bedrock. It's the foundation of the soil profile.

Practice Quiz

1. What is the uppermost layer of soil, primarily composed of organic material?
   1. A Horizon
   2. B Horizon
   3. O Horizon
   4. C Horizon
2. Which soil horizon is characterized by the accumulation of leached minerals, often clay?
   1. A Horizon
   2. B Horizon
   3. C Horizon
   4. E Horizon
3. In which horizon would you find partially weathered parent material?
   1. O Horizon
   2. A Horizon
   3. C Horizon
   4. R Horizon
4. Which horizon is also known as topsoil?
   1. O Horizon
   2. A Horizon
   3. E Horizon
   4. B Horizon
5. The process of leaching is most characteristic of which soil horizon?
   1. A Horizon
   2. B Horizon
   3. E Horizon
   4. C Horizon
6. What is the name for the bottommost layer of soil, composed of bedrock?
   1. A Horizon
   2. B Horizon
   3. O Horizon
   4. R Horizon
7. Which horizon is a mixture of organic material and minerals?
   1. O Horizon
   2. A Horizon
   3. B Horizon
   4. R Horizon