Theory

Soil heat and water characteristics must be defined for each compartment and thermal and unsaturated conductivity must be defined for each boundary between compartments in the soil profile. Available field data representing these properties seldom coincide exactly with the chosen discretization of the soil profile.

Continuous profiles of soil properties are obtained by linear interpolation between, and extrapolation outside of measurement or sampling depths (see Figure 6.5). From a continuous profile of a parameter, p (z), discrete parameter values are obtained for each compartment by:

                                                        (8.17)

where: z_i and z_i+1 are the upper and lower boundaries of compartment i. Conductivity parameters are calculated for each boundary between compartments by:

                                                (8.18)

 

Figure 6.5. Graphical representation of how the model calculates soil parameters to represent a soil profile.