Chapter 12: Soils

1. Loose, weathered material covering bedrock, a product of weathering.
3. The true soil, extending only through the B horizon.
5. Term for particle sizes in soil classification.
7. The smallest soil particles, made of silica and oxides, unique to soil.
8. Vertical section through soil layers down to the parent material.
9. Brown or black stable organic matter formed after decomposition.
11. Soil texture with balanced proportions of the three primary particle sizes.
13. Refers to the water volume soil holds after gravitational water drains.
14. Distinct layers within soil, each with unique characteristics.
15. Thin surface layer of mineral particles, organic matter, organisms, gases, and liquids.

2. Accumulated dead plant parts like leaves and twigs on the soil surface.
4. Process where water dissolves soil nutrients, making them available to roots.
6. Creatures that improve soil structure and fertility by mixing soil.
8. Clumps that soil particles aggregate into, determining soil structure.
10. Very fine soil particles, smaller than 0.1 micrometer in diameter.
12. Deep soils formed through laterization in tropical climates.