Across
- 5. Chemical change when when a substance combines with oxygen
- 6. rocks broken down chemically
- 9. management of soil to prevent destruction
- 11. The distance in elevation from Contour line to Contour line
- 12. rocks broken down physically
- 15. Darker contour line on a topographic map that rounds elevation units
- 17. plowing fields along curves of slopes to prevent soil loss
- 18. Loose layer and dead plant leaves and stems on the Suface of the soil
- 21. Anything in the environment that humans use
- 23. Dark colored organic material in soil
- 25. The process when water seeps into cracks, freezes and expands
- 27. Solid layer of rock beneath the soil
Down
- 1. The crumbly, topmost layer of soil, mixture of humus, clay, and other minerals
- 2. Principle that states that earth surface changed the same way forever
- 3. type of soil that is made up of about equal parts of clay, sand, and silt
- 4. thick mass of grass roots and soil
- 7. Method which dead stalks from the previous years crops are left in the ground to hold soil in place
- 8. A material that is full of tiny connected air spaces that water can seep through
- 9. Layer of soil beneath the topsoil, contains clay and other minerals
- 10. Rocks that break down on Earths Suface physically and chemically
- 13. Grinding away of rock by other rock particles carried in ice, water,or wind
- 14. When water, ice, wind, or gravity moves weathered rock or soil
- 16. A soil organism that breaks down the remains of organisms and digests them
- 17. Planting of different crops in fields each year to maintain soils fertility
- 19. A map that shows Suface area
- 20. measure of how well soil supports plant growth
- 22. Line that connects points with the same elevation on a topographic map
- 24. Horizon Layer of soil that differs in color and texture
- 26. area of the Great Plains where wind erosion caused soil loss in the 1930s