Across
- 1. difference in elevation
- 2. solid layer beneath soil
- 4. line that shows elevation on a topographic map
- 5. dark colored organic materials in soil
- 7. chemical/ physical process that breaks down rocks
- 10. when a substance combines with oxygen and forms rust
- 13. crops are left on soil from previous years; type of plowing
- 17. plowing fields along slope curves to prevent soil loss
- 18. rich soil made up of clay sand and silt
- 20. grinding away of rock
- 21. top layer of soil
- 22. a thick mass of grass roots and soil
- 23. loose layer of dead plant leaves and stems on the surface of soil
- 24. splits rock when water goes in cracks and freezes
- 26. loose material where plants can grow
- 27. area in Great Plains where erosion caused soil loss in the 1930's
- 28. how well soil supports plant growth
Down
- 1. process that uses chemical processes to break down rock
- 3. map that shows elevation
- 6. layer of soil beneath topsoil
- 8. geological principle; same processes that happened before happen now
- 9. darker or bolder contour line
- 11. planting f different crops in area of a field to keep soil fertility
- 12. type of weathering; rock is physically broken
- 14. management of soil to prevent destruction
- 15. anything in the environment humans use
- 16. layor of soil that differs from layers above and below it
- 19. characteristic; spaces that water can seep through
- 25. organisms that decompose soil
- 29. ice wind water and gravity moves rock