Salt Transport and Storage

Only convection is considered by the model i.e. dispersion/diffusion is not accounted for. Thus the salt transport in the soil is calculated as:

                                      (2.53)

where q_mat is the matrix water flow, q_bypass is the bypass water flow in the macro pores and c_Cldep is a parameter. If the flow of water is directed upwards there is no bypass flow and consequently the second term in eq. (2.53) is neglected.

The soil salt concentration, C_Cl(z), can be estimated by dividing the salt storage, S_Cl(z), with the soil water content in each layer. However, if some of the salts are adsorbed to particles in the soil (see switch Adsorption), soil salt concentration, C_Cl(z), is instead calculated as:

                                        (2.54)

where s_adc is an adsorption parameter that can vary with depth, θ is the soil water content and Δz is the layer thickness (see viewing function Adsorption function).