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Chapter 6 - Humans in the Biosphere
Across
4. farming strategy in which large fields are planted with a single crop, year after year
8. number of different species in the biosphere
10. resource that cannot be replenished by natural processes; called a(n) _?_ resource
11. increasing concentration of a harmful substance in organisms at higher trophic levels in a food chain or food web
12. increase in the average temperatures on Earth
Down
1. plants and animals that have migrated to places where they are not native; called _?_ species
2. atmospheric layer in which ozone gas is relatively concentrated
3. resource that can regenerate quickly and that is replaceable; called a(n) _?_ resource
5. in areas with dry climates, a process caused by a combination of poor farming practices, overgrazing, and drought that turns productive land into desert
6. biological diversity; the sum total of the variety of organisms in the biosphere
7. destruction of forests
9. species whose population size is rapidly declining and will become extinct if the trend continues; called _?_ species