ISSN: 2474-8846
Authors: Tuffour HO*, Asare J, Adjei-Gyapong T, Kumi SO and Abubakari A
The Modified Green-Ampt Surface Sealing (MGASS) infiltration model considers real field infiltration process, wherein dispersed soil sediments, especially clay particles are present in the infiltrating water, and also accounts for the processof surface sealing. In view of the changes in the concentration of the soil sediments as infiltration proceeds, the various physical parameters in the equation are likely to change. Ponded infiltration studies were conducted in the field on three different soils to examine these changes in the model parameters, and how they influence the infiltration process. The results were compared with simulated infiltration using the Green-Ampt (G-A) MGASS infiltration models. The G-A model is often used to characterize infiltration process in soil hydrology. The key parameters in the MGASS model were the saturated hydraulic conductivity of the surface seal formed during the infiltration of water, hydraulic head, and moisture deficit; for the G-A model, the parameters were the saturated hydraulic conductivity of the soil surface, hydraulic head and moisture deficit. The saturated hydraulic conductivity (Ks) of the soil surface was found to be the most sensitive parameter in the G-A model. The MGASS equation, on the other hand was highly sensitive to changes in hydraulic head (hf).
Keywords: Green-Ampt; Infiltration; MGASS model; Sensitivity; Surface seal
