Across
- 2. a large eco-system
- 7. plants
- 9. people who originated from a particular place
- 12. a large expanse of water
- 14. the recycling of nutrients between organisms
- 15. variety of living organisms
- 17. a large underwater eco-system
Down
- 1. permanently frozen soil
- 3. the dependence of two or more living organisms on eachother
- 4. maintaining the environment
- 5. a dry sandy eco-system
- 6. animals
- 8. the climate of an area
- 10. an invisible line that runs round the earth
- 11. tourism to natural areas
- 13. the surroundings in which an organism operates
- 16. a desert in africa