Across
- 3. the following of practices that protect the Earth's resources
- 8. all the water found on, above, or under the Earth's surface
- 10. pollution that comes from an unknown source
- 12. a place where freshwater and salty water meet; rivers and oceans meet; brackish water
- 13. an area of land that drains into a stream, river, lake or other body of water
- 15. something that causes pollution to air or water
- 17. extremely rapid growth of algae caused by too many nutrients in the water
- 18. the saltiness of a body of water
Down
- 1. water without salt
- 2. a measure of how clear water is
- 4. the process by which some organisms use the energy stored in chemical bonds to make their own food
- 5. pollution that comes from a single, identifiable source
- 6. a measure of how acidic or how basic a liquid is
- 7. water located below the surface
- 9. an organism used to monitor the health of an ecosystem
- 11. cold, nutrient-rich water moves from deep layers of the ocean up to the surface
- 14. relating to the ocean
- 16. a part of the Earth's surface that is covered by ocean water