Across
- 3. a gas needed for aerobic respiration
- 4. pH below neutral
- 6. soil consisting of decomposing organic matter
- 7. form the foundation of Earth's surface and contains minerals
- 9. primary energy source on Earth
- 12. type of soil with the smallest particle size
- 14. height
- 15. a mixture of gases surrounding the Earth's surface
Down
- 1. weather conditions
- 2. surface structure
- 5. exists in three states and covers about 70% of the Earth's surface
- 8. quantity of dissolved salt
- 10. measured in degrees Celsius
- 11. quantity of water vapour in the air
- 13. soil factors