Across
- 2. material that has pockets of air in it which water can go through
- 6. curves of a hill to prevent the loss of soil
- 8. connects points of the same height on a topographic map
- 9. difference of one contour line to the next
- 10. a process to break rock through wind or water or gravity or ice
- 11. dark colored material with plant and animal matter
- 13. soil that has differences in color and texture
- 14. when a rock is broke down into smaller peices
- 20. a change that makes rust
- 21. thick grass roots and soil
- 22. breaks down the remains of organisms and digest them
- 23. rich soil made up mostly of clay sand and silt
- 24. a contour line that's says the height
- 25. water goes into rock then freezes then expands
- 27. something that a person can use
- 28. soil under topsoil with clay and other minerals mixed in
- 29. plants can grow in this
Down
- 1. a process to break down rock
- 3. layer of rock under soil
- 4. map that shows elevation
- 5. to prevent soil destruction
- 7. process that operates now and then
- 12. breaks down rock by a chemical change
- 15. dead plant from the last year to keep soil fertility
- 16. rock particles carried by wind water and ice
- 17. dead plant leaves on the top of soil
- 18. top layer of soil mixed with humus and clay
- 19. measure of how soil supports the rate of plant growth
- 26. wind erosion in the 1930's to cause the loss of soil