Across
- 2. The careful use and protection of water resources.
- 4. Contamination of water by harmful substances.
- 8. An area of land that drains into a particular river, lake, or other body of water.
- 9. The process of removing salt from seawater to produce freshwater.
- 10. Liquid fossil fuel commonly called crude oil.
- 12. Any material or substance that occurs in nature and can be used by humans.
- 13. A region of the stratosphere containing high concentrations of ozone that absorbs harmful ultraviolet radiation.
- 14. The layer of gases surrounding Earth.
- 16. Energy-rich substances formed from the remains of ancient organisms.
- 19. An underground layer of permeable rock or sediment that stores and transmits groundwater.
- 22. Energy derived from heat within Earth.
- 25. Water that contains very low concentrations of dissolved salts.
- 27. The process by which water is added back into an aquifer.
- 29. A mineral containing metals that can be extracted and used.
- 33. A gaseous fossil fuel composed mainly of methane.
- 34. Water that has been used and contains dissolved or suspended wastes.
- 35. A mixture of pollutants that forms a haze in the atmosphere.
- 36. The most abundant gas in Earth's atmosphere.
- 37. Rain, snow, or other precipitation made acidic by air pollutants.
- 38. A fossil fuel formed from ancient plant remains.
- 39. Planning and controlling the use of natural resources to ensure their availability in the future.
- 40. Water containing high concentrations of dissolved salts.
Down
- 1. Contamination of the atmosphere by harmful substances.
- 3. Water located beneath Earth's surface in soil and rock.
- 5. Energy generated by moving air.
- 6. The amount of a renewable resource that can be used without reducing its availability in the future.
- 7. A mineral that does not contain metals and is used for various industrial purposes.
- 11. The upper surface of the zone of saturation.
- 15. Water found on Earth's surface, such as rivers, lakes, and streams.
- 17. A gas essential for most living organisms and combustion.
- 18. A mineral or rock containing enough valuable substances to be mined profitably.
- 20. The effect that human activities have on the natural environment.
- 21. Energy produced by moving water.
- 23. A resource that forms much more slowly than it is used and cannot be replaced quickly.
- 24. The warming of Earth's atmosphere caused by certain gases trapping heat.
- 26. Energy from the Sun.
- 28. A resource that can be replenished naturally in a relatively short period of time.
- 30. The process of removing minerals and other resources from Earth's crust.
- 31. The careful use and management of natural resources.
- 32. Energy released from the nucleus of an atom.