Across
- 2. The process of using recycled materials
- 4. An animal or plant threatened with extinction
- 6. A source of energy that does not harm the environment
- 9. The act of throwing away unwanted items
- 10. The layer of gas surrounding the Earth
Down
- 1. A natural resource that can be replenished
- 3. A gas that contributes to global warming
- 5. The gradual destruction of land due to lack of rain
- 7. A group of people working to protect the environment
- 8. A large area of forest destroyed by fire
- 11. The study of living things and their environment