Unit 4 APES Slides 1-38

4. Intermediate particle size
6. An ecosystem native to central North America.
8. The process by which fertile land becomes desert, typically as a result of drought, deforestation, or inappropriate agriculture.
9. The action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material
10. Largest particle size
14. Parent material. Rock that has undergone little weahering
16. Subsoil. Tiny rock particles that leach down from the topsoil
17. The layers of the soil
18. A diagram used to classify soil into one of 12 textural classes based on the percentage of sand, silt, and clay it contains
20. Smallest particle size

1. An ecosystem located in the Great Plains of North America.
2. Partially decomposed plant and animal matter
3. Molecular Nature of rock is changed due to reacting with water, oxygen, etc.
5. Physical Breakdown of rock by wind, water, cold, and heat
7. Ideal for farming. Moderate water retention.
11. Humus, Non-decomposed plant matter.
12. Topsoil. Organic matter mixed with weathered rock particles
13. A period of severe dust storms that greatly damaged the ecology and agriculture of the American and Canadian prairies during the 1930s.
15. Bedrock. Unweathered, solid rock.
19. Losens soil