Across
- 4. found only in one specific geographic area
- 5. gradual process of species becoming extinct
- 9. any material or organism in the biosphere, including water, soil, fuel, and plants and animals
- 11. technique using living organisms to detoxify a polluted area
- 12. use of resources at a rate that they can be replaced or recycled
- 14. any different environmental condition occurring along an ecosystem's boundaries
- 15. variety of ecosystems in the biosphere
- 16. the disappearance of a species when the last of its members dies
- 17. overuse of a species with economic value - a factor in species extinction
- 18. in a biological community, the number and abundance of different species
- 19. any natural resource available in limited amounts or replaces extremely slowly by natural processes
- 20. the number of different species living in a specific area
Down
- 1. technique of adding essential materials to a degraded ecosystem
- 2. increasing concentration of toxic substances, such as DDT, in organisms trophic levels increase in food chains or food webs
- 3. water pollution from nitrogen-rich and phosphorus-rich substances flowing into waterways, causing algal overgrowth
- 6. habitat loss from separation of an ecosystem into small pieces of land
- 7. variety of inheritable characteristics or genes in an interbreeding population
- 8. any resource replaced by natural processes more quickly than it is consumed
- 10. a large-scale dying out of a large percentage of all living organisms in an area within a short time
- 13. nonnative species deliberately or accidentally introduced into a new habitat