Across
- 3. an animal that is hunted and eaten by another animal
- 4. no longer existing anywhere on Earth
- 5. harmful substances released from vehicle engines (two words)
- 7. energy sources formed from ancient plants and animals (two words)
- 8. a stable and healthy relationship between elements in nature
- 12. a very large sea wave caused by an underwater disturbance (two words)
- 14. the natural home where a plant or animal lives
- 15. a sequence showing how energy passes between living organisms (two words)
- 17. damage to the environment caused by harmful substances
- 19. using resources in a way that does not harm the future
- 20. substances in the atmosphere that cause the Earth to warm (two words)
- 22. a long period with very little rainfall
- 23. able to be replaced naturally and not used up permanently
Down
- 1. non-native organisms that spread and damage local ecosystems (two words)
- 2. a group of similar organisms that can reproduce with each other
- 6. large-scale removal of forests by humans
- 9. supplying water to land in order to grow crops
- 10. the variety of living organisms in a particular area
- 11. materials from nature that people use for energy or production (two words)
- 13. to gradually disappear completely (phrasal verb)
- 16. food produced without artificial chemicals (two words)
- 18. a situation when land becomes covered with water
- 21. in danger of disappearing completely