Abstract
Results of computational experiments using a web-based three-dimensional multi-reaction transport simulation model, modified to include macroporosity, are presented. Two types of soil column experiments are simulated: one in which the soil matrix is devoid of macropores and the other in which preferential flow occurs through randomly positioned cells that simulate preferential paths. The advection-dispersion equation is solved in both environments for two different input load concentration cases at the top of the simulated soil column: one-point-source and two-point-source. It is found that the vertical Darcy fluxes in the simulated soil matrix with macropores are up to four times as high as those in the corresponding homogeneous soil column.