Earth Day Crossword

6. The surroundings or conditions in which a person, animal, or plant lives or operates.
7. Convert (waste) into reusable material.
9. Decayed organic material used as a plant fertilizer.
10. Reuse (discarded objects or material) in such a way as to create a product of higher quality or value than the original.
12. Able to be maintained at a certain rate or level.
14. The branch of biology that deals with the relations of organisms to one another and to their physical surroundings.
16. An odorless, colorless gas made up of three oxygen molecules (O3) and is a natural part of the environment
17. (of a species, family, or other group of animals or plants) having no living members; no longer in existence.
18. Trash, such as paper, cans, and bottles, that is left lying in an open or public place.
19. (of a natural resource or source of energy) not depleted when used.

1. Relating to or derived from living matter.
2. Maintain (something) in its original or existing state.
3. The envelope of gases surrounding the earth or another planet.
4. A place to dispose of refuse and other waste material by burying it and covering it over with soil, especially as a method of filling in or extending usable land.
5. Contaminate (water, air, or a place) with harmful or poisonous substances.
6. The production and discharge of something, especially gas or radiation.
8. A biological community of interacting organisms and their physical environment.
11. Protect (something, especially an environmentally or culturally important place or thing) from harm or destruction.
13. Relating to or determined by the sun.
15. The natural home or environment of an animal, plant, or other organism.