Across
- 4. this process releases water vapour from oceans
- 9. a process which releases carbon dioxide out of fossil fuels
- 10. plants which are commonly associated with nitrogen-fixing bacteria
- 11. this reduces the amount of nitrate in the soil
- 12. water vapour can be released from plants by this process
- 13. how animals and plants release carbon dioxide into the atmosphere
Down
- 1. this occurs to dead organisms when decay is prevented
- 2. an animal source of nitrogen
- 3. the organisms which release ammonia or carbon dioxide from detritus
- 5. nitrifying bacteria turn this into nitrite
- 6. how water is released from the atmosphere to fall on earth
- 7. this reduces carbon dioxide levels in the atmosphere
- 8. the carbon-rich molecule produced during photosynthesis