soil_nutcarb_init Subroutine

subroutine soil_nutcarb_init(isol)

~ ~ ~ PURPOSE ~ ~ ~
this subroutine initializes soil chemical properties
and intial soil layer bmix efficiency

set soil nutrient initialization from nutrients.sol assume 0.001% carbon if zero calculate initial nutrient contents of layers, profile and average in soil for the entire watershed

set initial mineral pools - no3 mg/kg => kg/ha

assume initial concentration of 5 mg/kg mg/kg => kg/ha

set active mineral P pool based on dynamic PSP MJW Allow Dynamic PSP Ratio convert to concentration PSP = -0.045log (% clay) + 0.001(Solution P, mg kg-1) - 0.035*(% Organic C) + 0.43 Limit PSP range Set Stable pool based on dynamic coefficient From White et al 2009 convert to concentration for ssp calculation estimate Total Mineral P in this soil based on data from sharpley 2004 limit SSP Range the original code set initial organic pools - originally by Zhang initialize total soil organic pool - no litter kg/ha = mm * t/m3 * m/1,000 mm * 1,000 kg/t * 10,000 m2/ha total mass of soil organic matter - cbn in %, and assume SOM is 58% carbon initialize CENTURY organic pools - set soil humus fractions for CENTURY from DSSAT frac_not_seq is the residue/litter share derived from the user-supplied init_seq (carbon.bsn) initialize passive humus pool initialize slow humus pool original method. This is the default method initialize microbial pool metabolic residue

lignin residue

non-lignin residue

end soil layer loop

Arguments