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7. Modeling Atmosphere-Ocean Interactions and Primary Productivity
which is accompanied by a draw-down of atmospheric pC0 2 (Cooper et al.
1996).
Uptake of nitrate after addition of iron can be approximated (Coale et al.
1996) by a simple Michaelis-Menten function of uptake velocity (V N03 J as a
function of substrate concentration (Fe), the maximum uptake velocity
(V ma
) and the concentration of Fe supporting half saturated uptake (K)
where V N03
' =1/2 V max :
(3)
Equation (3) is used in Figure 7.3, to calculate N0 3
- uptake, or the conversion of dissolved inorganic N to particulate N that is then removed to deep
water. K, is set to SpM and VmaxNto .11 mol per year.
Bottom N03
Cone of Surf N03
C:N03 Ratio
Cone of Surface Fe
N03 Remineralization
Sedimentary N03
FIGURE 7.3