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CH1011
BIOGEOCHEMICAL CYCLES
• Global environmental problems must
deal with the three major elemental reservoirs (atmosphere, hydrosphere and the geosphere).
• We will use the expression biogeochemical cycles  to describe the process where elements are cycled between the three reservoirs often with the involvement of the biota (also just called geochemical cycles).
• Each element has unique features in it’s biogeochemical cycle. We will look at the
C cycle to illustrate some of the important features of such cycles.