Calcium Pools and Fluxes in the Biosphere

In the oceanic soluble organic matter a reasonable average Ca content is 0.5%, and it represents 20 x 10 tons in the corresponding reservoir. 

The water soluble inorganic calcium compounds, most commonly bicarbonate, Ca(HC03)2, leaches permanently to river waters and finally migrates to the ocean. This bicarbonate forms in the reactions of calcium carbonate with carbonic acid. 

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