Across
- 4. take in carbon dioxide and release oxygen
- 8. taking up nutrients by roots
- 11. decomposers turning waste into ammonia
- 13. conversion of nitrites into nitrates
Down
- 1. sinking of water into the ground
- 2. process plants use to draw water from the ground
- 3. process of plants and animals to release carbon dioxide
- 5. dead materials that sink to the bottom of the ocean
- 6. conversion of nitrates to nitrogen gas
- 7. excess nutrients entering aquatic ecosystem
- 9. burning fossil fuels
- 10. the removal of nutrients as water passes through soil
- 12. breakdown of nutrients which allows soil to become nutrient rich