Biology Unit 9

4. The amount of biological or living diversity per unit area. It includes the concepts of species diversity, habitat diversity and genetic diversity
5. A gradual increase in the overall temperature of the earth's atmosphere
6. Dark layer of the oceans below the photic zone where sunlight does not penetrate
9. Release of harmful materials into the environment
12. The removal of trees faster than forests can replace themselves
14. Species that enter new ecosystems and multiply, harming native species and their habitats
16. A stable, mature community that undergoes little or no change in species over time
18. Biomes on land (forests, taiga, tundra, etc.)
19. Portion of the marine biome that is shallow enough for sunlight to penetrate
20. Succession following a disturbance that destroys a community without destroying the soil

1. A community of organisms where there are several interrelated food chains
2. An ecological succession that begins in an area where no biotic community previously existed
3. A habitat in which the freshwater of a river meets the salt water of the ocean
7. First species to populate an area during primary succession
8. A species that is found in its originating location and is generally restricted to that geographic area
10. A situation in which the number of people in an area exceeds the capacity of the environment to support life at a decent standard of living
11. A group of ecosystems with similar climates and organisms
13. A species that influences the survival of many other species in an ecosystem
15. Biomes that are in or have to do with water: They are either freshwater or saltwater
17. An organism made of a fungus and either algae or autotrophic bacteria that live together in a mutualistic relationship