Submitted to: Hydrological Processes
Publication Type: Peer reviewed journal
Publication Acceptance Date: 9/1/2002
Publication Date: N/A
Citation: Interpretive Summary: Managing soil salinity remains an important problem in many regions. Influx of salts into soil from shallow ground water is a cause of salinity in many instances. Increasing the amount of irrigation water may prevent the soil salinization, but it can also cause the rise of the ground water level and increase the need for drainage and salinization sources of the irrigation water. Therefore, there is a need in predictive models to estimate soil salinization as affected by the irrigation schedule and ground water salinity. Both analytical and numerical solutions of the equations in solute transport models are studied and used. This work presents the first analytical solution for the two-region solute transport model in finite layer that takes into account the effect of ground water salinity on the soil salinity. This analytical solution assumes a steady-state water flow and constant in time and space dispersivity coefficient, and therefore the applicability of this solution is limited. However, this analytical solution can be useful in providing initial estimates of alternative salinization and desalinization scenarios when implemented over large temporal and spatial scales. Our analytical solution also provides a useful tool for sensitivity analysis to investigate effects of various transport parameters and can be easily incorporated in stochastic approaches to simulate solute transport in heterogeneous soils.
Technical Abstract: Managing soil salinity remains an important problem in many regions. As knowledge about solute transport has accumulated, solute transport models have been developed that accounted for a number of processes in salt-affected soils. Analytical solutions for solute transport in finite layer are of interest when the salt transport in soils occurs in presence of shallow ground water. Observations of salt concentrations in ground and irrigation water coupled with water balance estimation can provide necessary data to apply the analytical solution for the finite soil layer to access salt transport in soil at field scale. The objective of this work was to develop an analytical solution for the two region solute transport model in finite layer that would take into account the effect of ground water salinity on the soil salinity. The solution is developed using the Laplace transform. Expressions to estimate the total solute mass in soil profiles are given.