ISSN:
1365-2389
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Geosciences
,
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
Notes:
The migration of colloidal particles in the unsaturated zone may enhance leaching of sorbing contaminants to surface waters and groundwaters. This paper describes a simple model of particle leaching and translocation based on the dual-porosity model MACRO. The model includes descriptions of processes such as ‘source-limited’ particle detachment due to the kinetic energy of rain, replenishment of the depleted store of particles up to a maximum value determined by the amount of dispersible clay in the soil, and convective transport of particles in macropores subject to a filter sink term varying as a function of pore water velocity. Estimates of model parameter values are obtained by comparing simulations with measurements of particle concentrations in the discharge from tile drains made in a silty clay soil in southwest Sweden. Calibrated in this way, the model is shown to reproduce satisfactorily the observations. A sensitivity analysis suggests that the critical parameters in the model are those related to particle filtering during vertical transport in soil macropores.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1365-2389.1999.00269.x