Question about technical note 2.7_(2.7.60 to 2.7.63)_How were the ranges of values for these hydraulic parameters in soil organic matter determined?

[Shenning]

Hello everyone,
I would like to draw on the ideas from FuncPedotransferMod to introduce new variables A and B in the CLM model through soil texture parameters such as Sand and Clay. However, I found the following description when calling the soil water characteristic curve in the initialization module SoilStateInitTimeConstMod:
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ipedof=get_ipedof(0)
call pedotransf(ipedof, sand, clay, &
soilstate_inst%watsat_col(c,lev), soilstate_inst%bsw_col(c,lev), soilstate_inst%sucsat_col(c,lev), xksat)

om_watsat = max(0.93_r8 - 0.1_r8 *(zsoi(lev)/zsapric), 0.83_r8)
om_b = min(2.7_r8 + 9.3_r8 *(zsoi(lev)/zsapric), 12.0_r8)
om_sucsat = min(10.3_r8 - 0.2_r8 *(zsoi(lev)/zsapric), 10.1_r8)
om_hksat = max(0.28_r8 - 0.2799_r8*(zsoi(lev)/zsapric), xksat)

soilstate_inst%bd_col(c,lev) = (1._r8 - soilstate_inst%watsat_col(c,lev))*2.7e3_r8
soilstate_inst%watsat_col(c,lev) = (1._r8 - om_frac) * soilstate_inst%watsat_col(c,lev) + om_watsat*om_frac
tkm = (1._r8-om_frac) * (8.80_r8*sand+2.92_r8*clay)/(sand+clay)+om_tkm*om_frac ! W/(m K)
soilstate_inst%bsw_col(c,lev) = (1._r8-om_frac) * (2.91_r8 + 0.159_r8*clay) + om_frac*om_b
soilstate_inst%sucsat_col(c,lev) = (1._r8-om_frac) * soilstate_inst%sucsat_col(c,lev) + om_sucsat*om_frac
soilstate_inst%hksat_min_col(c,lev) = xksat
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I would like to know how the value ranges for these soil hydraulic parameters in soil organic matter are determined, and if there are any corresponding references. If I want to similarly add other variables A and B, how should I determine their corresponding value ranges in soil organic matter?

I only found the description as shown in the figure in Technical Note 2.7, and I hope to get a more detailed explanation. Thank you.

 

[slevis]

I expect that the Technical Note and its references contain the most detailed explanations pertaining to these equations. I think you are likely best off digging into the relevant references and possibly contacting their authors.