land: aerobic respiration, photosyntehsis
sea: partial pressure, photosynthesis co2 dissolved in water |
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Humans: clear trees, butn fossil fuels |
Nitrogen cycle: nitrogen fixation N2 → NH3 (and NH4+)
Nitrification: NH3 → NO2, NO3 |
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Denitrication: NH3 and NH4+ to N2 |
phosphorus cycle
from water, taken up by plants. Decomposers break down. |
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Burn coal&oil, refine petroleum, convert sulphur containing metallic ores into free metals |
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Speciation, extinction, biodiversity |
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Speciation: 1) Allopharic speciation, geographic isolation; 2) Sympatric speciation, mutations |
Extinction:
Background extinction (all species are condemned to die)
Mass extinction (meteorite)
Mass depletion (reduction of number individual of species) |
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See more notes on course homepage |
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Before exam 3
EnvSc
Lecture 3
Ecosystem 1
Exam & Assignments