VSD+
From VLECK
input structure
TYPE | mod | var | description | units |
integer | modExc | cation exchange model option: 1=Gaines-Thomas, 2=Gapon | ||
real | dt | time stepsize | dy | |
real | pCO2 | partial CO2-pressure in soil solution | atm | |
real | KAlox | Al equilibrium constant | (eq/m3)^(1-expAl) | |
real | expAl | exponent in [Al]=eqK%Alox*[H]^expAl | ||
real | thick | soil thickness | m | |
real | rho | bulk density | g/cm3 | |
real | theta | volumetric water content of the soil | m3/m3 | |
real | thetao | volumetric water content of the soil at previous timestep | m3/m3 | |
real | thetasat | volumetric water content of the soil at saturation | m3/m3 | |
real | thetafc | volumetric water content of the soil at field capacity | m3/m3 | |
real | theta1bar | |||
real | thetawp | volumetric water content of the soil at wilting point | m3/m3 | |
real | CEC | cation exchange capacity of the soil | meq/kg | |
real | KAlBc | selectivity constant for Al-Bc exchange | ||
real | KHBc | selectivity constant for H-Bc exchange | ||
real | temp | average soil temperature | oC | |
real | ps | precipitation surplus | m | |
real | coacid | total concentration of organic acids (m*DOC) | mol/m3 | |
real | *3 | pKpar(3) | 1-3 parameters of (Oliver-type) mono-protic organics model: pK = pKpar(1)+pKpar(2)*pH-pKpar(3)*pH^2 | |
real | kni | maximum nitrification rate at Tref | yr-1 | |
real | kde | maximum denitrification rate at Tref | yr-1 | |
real | Nfix | N fixation rate | eq/m2/yr | |
real | Clf | C litterfall | g C/m2 | |
real | ctclay | clay content of the soil | % | |
real | Calc | Fraction Ca in carbonates -1 = no carbonates in soil, 0 = pure MgCO3, 1 = pure CaCO3 (e.g. for dolomite Calc = 0.5) || - | ||
type(Ions) | Wea | weathering rate of X note:: is zero for NO3, NH4, Cl|| eq/m3/yr | ||
type(Ions) | Dep | deposition rate of X | eq/m2/yr | |
type(Ions) | Lf | litterfall of X note: VSDp will sum litterfall of NO3 and NH4; is zero for SO4, Na, Cl |
eq/m2 | |
exchange structure
TYPE | mod | var | description | units |
integer | istart | start flag; if true: initialise certain variables for use in simulation; set to false afterwards (see NOTES) | ||
real | CNrat | C:N ratio in topsoil | g/g | |
real | Csoil | organic C content of soil | g/m2 | |
real | cH | H+ concentration | eq/m3 | |
real | ECa | exchangeable fraction of Ca | ||
real | EMg | exchangeable fraction of Mg | ||
real | EK | exchangeable fraction of K | ||
real | *10 | CN(10) | CN ratio of the C pools | - |
real | *10 | Cpool(10) | size of C pools | g/m2 |
real | Nbal | (no doc) | ||
type(Ions) | Upt | net uptake of X note:: VSDp will modify distribution of N uptake over NO3 and NH4; is zero for SO4, Na, Cl |
eq/m2 | |
type(Ions) | Conc | concentration of ion X (SO4,NO3,NH4,Ca,Na,Cl) | eq/m3 | |