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Sorption Isotherm Spreadsheet

    Spreadsheet from the paper entitled: On the Use of Linearized Langmuir Equations by C.H. Bolster and G.M. Hornberger, Soil Science Society of America Journal, 2007, 71(6): 1796-1806.

    Modified Langmuir Equation Spreadsheet

      Spreadsheet from the paper entitled: Revisiting a Statistical Shortcoming when Fitting the Langmuir Model to Sorption Data by C.H. Bolster, Journal of Environmental Quality, 2008, 37:1986-1992. Spreadsheet has been modified to make a correction to the calculation of E for weighted data. (3/18/2010).

      WATSUIT

        Predicts the salinity, sodicity, and toxic-solute concentration of the soil-water within a simulated crop root zone resulting from the use of a particular irrigation water of given composition and at a specified leaching fraction. It can be used to evaluate the effect of a given salinity level (or solute concentration) on crop yield and of a given sodicity level on soil permeability.

        UNSATCHEM

          Simulates water, heat, carbon dioxide and solute movement in one-dimensional variably saturated media.

          SWMS-3D

            Simulates water and solute movement in three-dimensional variably saturated media.

            SWMS-2D

              Simulates water and solute movement in two-dimensional variably saturated media.

              STANMOD

                Computer Software for Evaluating Solute Transport in Porous Media Using Analytical Solutions of the Convection-Dispersion Equation.

                N3DADE

                  Evaluates analytical solutions for two- and three-dimensional non-equilibrium solute transport.

                  HYDRUS-1D

                    HYDRUS-1D is a Microsoft Windows-based modeling environment for analysis of water flow and solute transport in variably saturated porous media. The software package includes the one-dimensional finite element model HYDRUS (version 7.0) for simulating the movement of water, heat, and multiple solutes in variably saturated media. The model is supported by an interactive graphics-based interface for data-preprocessing, discretization of the soil profile, and graphic presentation of the results.