"Evolution of Global Biogeochemical Cycles"
Five of the major elements that comprise all organisms
(H, C, N, O, and S)
are biogeochemically coupled through a series of linked redox reactions. Of
these five elements, C and N were oxidized in the early formation of Earth.
Reduction can through electron donation from S and H2. Using the nitrogen
cycle as a model, I will trace the evolution of several biogeochemical cycles
and examine how they operate in the contemporary world to constrain the
global carbon cycle.