Across
- 3. activities that reduce our environmental impact
- 6. layer that covers the city caused by harmful gases
- 7. a way to get as much as we can from things
- 9. change that happens because of some action
- 10. material that is not made fast
- 13. top producer of guano
- 16. energy that comes from the movement of water
- 17. something found in nature
- 18. verb that describes the fuel when it burns
- 20. presence of harmful substances in the environment
- 21. substances made up of one or more minerals
- 22. a device that changes the energy of sunlight
Down
- 1. the rock and solid beneath and around us
- 2. place where hunting eliminated all the wolves
- 4. the living things on earth
- 5. the water on earth
- 8. provides air that we breathe
- 11. flammable gas used to generate electricity
- 12. seabirds droppings
- 14. material made by nature
- 15. can also be used to produce electricity
- 19. nonliving solids in Earth's crust
- 23. put into groups