Across
- 2. the ability to keep in existence natural resources in order to maintain an ecological balance
- 4. any community of living and nonliving things that work together
- 7. all the water on earth
- 10. the solid part of the Earth consisting of the crust and the outer mantle
- 12. a term that typically describes a species that no longer has any known living individuals
- 14. materials or substances such as minerals, forests, water, and fertile land that occur in nature and can be used for economic gain
- 18. a record of geologic events and ife forms in Earth's history
- 20. the variety of life in the world or in a particular habitat or ecosystem
- 21. the change form food gathering to food production
- 22. any natural resource that can be replenished in a relatively short period of time
Down
- 1. a thin layer of gases surrounding Earth
- 3. human's impact on the Earth
- 5. an undesired change in the air, water, or soil that adversely affects the health, survival, or activities of humans or toher organisms
- 6. the part of the Earth where life exists
- 8. the impact of a person or community on the environment expressed as the amount of land required to sustain their use of natural resources
- 9. the transformation from an agricultural to an industrial
- 11. a principle the geologic processes that occurred in the past can be explained by current geologic processes
- 13. pollutants that cannot be broken down by natural processes
- 15. pollutants that can be broken down by natural processes
- 16. a large extinction of species in a relatively short period of time
- 17. all the living things in an ecosystem
- 19. non-living things in an ecosystem
