New ppn definition

[gbolzon]

Applicable only for bfm version neccton v20
(see also the PR)

BFM version 5.3 (Neccton version) has new formulation for

• chlorophyll synthesis now based on netPP (and no more on grossPP)
• consequently p_alpha_chl and p_qlcPPY parameters have been adjusted
• a quota of exudation for nutrient stress is directly consumed as respiration (new parameter p_pu_m equals to 0.35 for all PFTs) The idea is that the cell consume energy to produce and release exudates when the lack of nutrient does not allow the net growth.

Then, the net primary production definition has been corrected and now it is the gross primary production minus the total respiration: ppn = ruPPYc - resPPYc
This mean that ppn include both the particulate net primary production (carbon fixed in particulate organic form) and the dissolved net primary production (carbon fixed in the dissolved organic form -which is exusated- )

[gbolzon]

<aggvar name="R_c" formula="R_c = R1c + R2c + R6c + R3c" > </aggvar>
becomes
<aggvar name="R_c" formula="R_c = R1c + R2c + R6c + R3c + R8c" > </aggvar>

<aggvar name="R_p" formula="R_p = R1p + R6p " > </aggvar>
becomes
<aggvar name="R_p" formula="R_p = R1p + R6p + R8p " > </aggvar>

<aggvar name="POC" formula= "POC = P_c + R6c + B1c + Z3c + Z4c + Z5c + Z6c" ></aggvar>
becomes
<aggvar name="POC" formula= "POC = P_c + R6c + B1c + Z3c + Z4c + Z5c + Z6c + R8c" ></aggvar>

[gbolzon]

<aggvar name="exR2ac" formula= "exR2ac = BFM1D_exR2ac_iiP1 + BFM1D_exR2ac_iiP2 + BFM1D_exR2ac_iiP3 + BFM1D_exR2ac_iiP4 " ></aggvar>

può essere tolto dal bfm e da ogstm

[gbolzon]

@gcossarini, shall we maintain two ppn definitions?
Should postproc be able to detect the bfm version?

[gcossarini]

No, only one definition should be maintained.
If the BFM model is the NECCTON version, we have the new npp definition.
If the BFM model is the old version (before or different from neccton version), we should kept the previous npp definition.