Environmental Crossword #2

3. A large natural stream of water flowing in a channel to the sea, a lake, or another such stream
4. Frozen water
7. Makes the noise "meow"
8. Natural electrical phenomenon in the sky (reddish or greenish light) usually near the northern or southern magnetic pole
9. Decayed organic material used as a plant fertilizer
10. Water that has once been used in a home, in a business, or as part of an industrial process
13. A tower or other structure containing a beacon light to warn or guide ships at sea
15. 97 percent of salt water makes up the world's?
16. A building with sails or vanes that turn in the wind and generate power to grind grain into flour
19. A natural fuel such as coal or gas, formed in the geological past from the remains of living organisms
20. Is a piece of mineral crystal which, in cut and polished form, is used to make jewelry or other adornments
21. Any of a group of spore-producing organisms feeding on organic matter, including molds, yeast, mushrooms, and toadstools

1. Leakage of petroleum onto the surface of a large body of water
2. The cutting down of trees in a large area; the destruction of forests by people.
5. Many species of plants and animals are in danger of/threatened with extinction (= being destroyed so that they no longer exist)
6. A mountain with a large circular hole at the top through which lava and other substances are forced out
11. An animal that is called "man's best friend"
12. A luxuriant, dense forest rich in biodiversity, found typically in tropical areas with consistently heavy rainfall
14. Plant that retains green leaves throughout the year
17. A barren area of landscape where little precipitation occurs
18. The Titanic hit one of these
22. Spring, summer, autumn, and winter