TABLE 3.
Modeled processes
| Process | Equation | Unit | Description |
|---|---|---|---|
| P |
g1 ( ) × (1 − lC) × aC × 12 × Cs
|
mmol C · m−3 · h−1 | Actual gross photosynthesis rate |
g1( ) |
Pm × [1 − exp(− /Ik)] × exp(− /βl) |
mol C · g Chla−1 · h−1 | P-I curve (41) |
| g2(Cr) | c1 × Cr | mmol C · m−3 · h−1 | Carbon flux from Cr to Csm (catabolism) |
| g3(Csm) | c2 × lC × Cs | mmol C · m−3 · h−1 | Carbon flux from Csm to Cr (storage) |
| g4 | c3 × MIN {[1 − g5(N1)], [1 − g6(Ne)]} × g7(Ce) | mol N · mol C−1 · h−1 · h−1 | Synthesis of nitrogenase activity |
| g5(N1) | N1/(N1 + kd) | Limitation due to presence of nitrate | |
| g6(Ne) | Ne6/(kN6 + Ne6) | Limitation due to Ne | |
| g7(Ce) | Ce6/(kCn6 + Ce6) | Limitation due to Ce | |
| g8 | c4 × g9(Nit) × g7(Ce) | mol N · mol C−1 · h−1 · h−1 | Breakdown of nitrogenase activity |
| g9(Nit) | Nit/(Nit + c5) | Decay scaled to nitrogenase activity | |
| F | Nit × (1 − lN) × g10(Ce) × Cs | mmol N · m−3 · h−1 | Actual N2 fixation rate |
| g10(Ce) | Ce6/(kCf6 + Ce6) | Limitation due to availability of DIN | |
| U1 | c6 × lC × g11(N) × (1 − lN) × Cs × N1/N | mmol N · m−3 · h−1 | Actual nitrogen uptake rate |
| U2 | c6 × lC × g11(N) × (1 − lN) × Cs × (1 − N1/N) | mmol N · m−3 · h−1 | Actual ammonium uptake rate |
| g11(N) | N/(N + kd) | Limitation due to availability of DIN | |
| G | gm × MIN(lC, lN) × Cs | mmol C · m−3 · h−1 | Actual gross production of structural biomass Cs |
| ra1 | if N ≤ 10−5, c7; otherwise, c8 + (c7 − c8) × (1 − N1/N) | Minimum fraction of the gross growth (Cs production) lost as respiration activity | |
| ra | ra1 + (ra2 − ra1) × [1 − g11(N)] × G | mmol C · m−3 · h−1 | Actual loss due to respiration activity |