Sk. Kamra et al., EFFECT OF DEPTH OF IMPERVIOUS LAYER AND ADSORPTION ON SOLUTE TRANSPORT IN TILE-DRAINED IRRIGATED LANDS, Journal of hydrology, 155(1-2), 1994, pp. 251-264
A two-dimensional finite element model of solute transport in a tile-d
rained soil-aquifer system was applied to study the effect of the dept
h of impervious layer and adsorption on salt distribution in the soil
and groundwater, and the salinity of drainage effluent. The model cons
iders steady state water flow in the unsaturated and saturated zones,
and includes the effect of convective transport, dispersion and linear
adsorption. The results indicate that though the depth of the impervi
ous layer has little effect on salt distribution in the unsaturated zo
ne, it significantly influences the quality of the drainage effluent.
Further, it was found that during the initial years of reclamation of
a highly saline soil with subsurface drainage, the effect of adsorptio
n is more pronounced in the unsaturated zone than in the saturated zon
e and the movement of adsorbing solute species is retarded for a longe
r time in the groundwater than in the soil.