Across
- 2. soil beneath the topsoil that contains mostly clay
- 3. lose weathered material wear plants can grow
- 6. line that connects equal points of elevation
- 7. process that breaks rock through chemical changes
- 11. plowing field along the curves of a slope to prevent soil loss
- 12. same principle used in the past is used today
- 13. chemical and physical process that breaks up rock
- 15. water wind ice and gravity move weathered rock
- 16. area in the Great Plains where wind erosion caused loose soil in the 1930
- 17. map that shows feature of an area
- 19. water seeps into rock freezes then expandes
- 20. soil organisms that break down the remains of organisms
- 23. dead stalks left in the ground to hold the soil in place
- 26. solid layer of rock beneath the soil
- 28. anything in the environment humans use
Down
- 1. rotation planting different crops each year to maintain the soils fertility
- 2. management of soil to prevent its destruction
- 4. loose layer of dead plant leaves and stems on the surface
- 5. rock is physically Brocken down into smaller pieces
- 8. rich soil mad up of clay sand and silt
- 9. mixture of humus clay and other materials that forms topmost layer of soil
- 10. thick mass of grass roots and soil
- 14. heavier contour lines that shows elevation in round units
- 18. dark colored organic material in soil
- 21. material that is full of tiny air spaces
- 22. layer of soil that differs in color and texture
- 23. difference in elevation from each contour line
- 24. grinding away rock particles by wind water or ice
- 25. chemical change in which a substance combines with oxygen and rust
- 27. measure of how well soil supports plant growth