Across
- 2. Energy sources that are naturally replenished.
- 7. Variety of plant and animal life in an ecosystem.
- 8. Capable of being decomposed naturally by bacteria or other organisms.
- 9. Species at risk of extinction.
- 12. Grown without synthetic pesticides or fertilizers.
- 13. Gases or substances released into the atmosphere.
- 14. Decayed organic material used as fertilizer.
- 15. Contamination of air, water, or soil.
Down
- 1. The cutting down of forests.
- 3. Able to be maintained at a steady level without exhausting resources.
- 4. Energy from the sun.
- 5. An element released by burning fossil fuels.
- 6. A structure that traps heat, often related to global warming.
- 10. A natural community of plants and animals.
- 11. Protecting Earth's natural resources.