Suction -p*(dl.Hp<0) "Current suction"
PorePressure p*(dl.Hp>=0) "Pore pressure"
k_rel Se "Relative permeability"
k K_sat*muw/gammaw "Soil permeability"
Cm phi0*(S_sat-S_res)*Se*alpha "Specific moisture capacity"
Se exp(alpha*dl.Hp)*(dl.Hp<0)+1*(dl.Hp>=0) "Effective saturation"