Across
- 4. organisms that break down and digest the remains of organisms
- 6. weathered material in which plants can grow on
- 7. layer of soil under the topsil which made of clay and other minerals
- 9. the difference in elevation represented by each contour line
- 11. mass of grass that is thick
- 12. chemical changes that break down rock
- 16. a theory that present processes in nature explain geological changes in the past
- 18. layer of rock beneath the soil
- 23. changing crops each year to keep soil's fertility
- 25. the process in which rock breaks down at Earth's surface
- 26. a chemical change when oxygen is combined with iron oxidizes to form rust
- 27. process in which last years dead stalks are left in the ground to hold the soil in place
- 29. a map that shows surface features of a particular area
Down
- 1. preventing soil loss by plowing along the curves of fields
- 2. the process by which soil and rock are removed from the Earth's surface
- 3. lines a line on a map that joins points of equal height
- 5. organic material in soil
- 7. managing soil to prevent it from being destroyed
- 8. dead plant leaves and stems on top of the soil
- 10. weathering were rock is broken down into smaller pieces
- 13. rich soil that is made up of silt, sand, and clay
- 14. soil layer that is different then the layers on top and below
- 15. the scraping of rock by firction during water, wind, or ice
- 17. process when there is a crack in rock, water gets in and freezes, breaking the crack even bigger
- 19. how well soil can support plant life
- 20. tiny pores in which water can seep through
- 21. a thick line on a topographical map labeled with the elevation it represents
- 22. anything humans use in the environment
- 24. in the 1930's Great Plains in which wind erosion caused loss of soil
- 28. the crumbly layer of soil made up of clay, humus, and other minerals