Across
- 3. Trash left lying somewhere
- 6. Production and release of gas
- 7. Surrounding of an organism
- 9. Study of organisms relations
- 10. Gas protecting us from the sun
- 12. Place of living
- 14. Gone forever
- 16. Keep safe
- 19. Ruin or contaminate
Down
- 1. Places for waste to go to
- 2. Able to be used
- 4. Waste that is reused
- 5. Organic material used as fertilizer
- 8. Community of interacting organisms
- 11. From nature
- 13. Keep in original state
- 15. Layer of gas surrounding a planet
- 17. Able to be reused
- 18. Energy coming from light