Human Impacts on Earth's Systems
Across
- 4. a natural substance made from one or more minerals
- 7. a naturally occurring, non living substance
- 9. the protection and care of forests, rivers, and other natural resources
- 10. able to produce the effect wanted without wasting time or energy
- 11. a material supplied by nature that is used by humans and other organisms
- 12. a change that happens because of some kind of action
- 13. material made by nature at least as quickly as people use it
Down
- 1. a resource that is replenished at a slower rate than it is used
- 2. the presence of harmful substance in the environment
- 3. energy produced by moving water
- 5. to organize into groups based on a system
- 6. to change in form
- 8. a mixture of methane and other gases formed underground and used for energy