Soil Hydraulic Models Selection Based on In-Situ Measurements
Publication: Journal of Irrigation and Drainage Engineering
Volume 124, Issue 6
Abstract
Soil hydraulic properties are usually expressed as functional relationships between the soil hydraulic conductivity and water content or matric potential, and between the matric potential and water content. Both functions are highly nonlinear, and direct in-situ measurements are time consuming and involve considerable uncertainty. Therefore, methods based on soil hydraulic models, i.e., functions chosen a priori and containing parameters estimated from measurements, are of interest. The most widely used models are those of Gardner in 1958, Russo in 1988, Brooks and Corey in 1964, and van Genuchten in 1980. For such models, an equation is derived that relates the developed expression for the first moment, M, of the diffusivity function with a combination of measured parameters: saturated hydraulic conductivity, capillary length, saturation and residual water content, and soil sorptivity. The M expressions are derived for the three models in the form of explicit functions of their parameters. Three overlapping M ranges are determined where the selection of a respective model is preferable.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
Abramowitz, M., and Stegun, I. A. (1968). Handbook of mathematical functions. Dover Publications, Inc., New York, 883.
2.
Brooks, R. H., and Corey, A. T. (1964). “Hydraulic properties of porous media.”Hydro. Paper 3, Colorado State University, Fort Collins, Colo.
3.
Brutsaert, W.(1967). “Some methods of calculating unsaturated permeability.”Trans. ASAE, 10, 400–404.
4.
Clothier, B. E., and White, I.(1981). “Measurement of sorptivity and soil water diffusivity in the field.”Soil Sci. Soc. Am. J., 45, 241–245.
5.
Gardner, W. R.(1958). “Some steady state solutions of unsaturated moisture flow equations with application to evaporation from a water table.”Soil Sci., 85, 228–232.
6.
Kool, J. B., and Parker, J. C.(1988). “Analysis of the inverse problem for transient unsaturated flow.”Water Resour. Res., 24, 817–830.
7.
Kool, J. B., Parker, J. C., and van Genuchten, M. T.(1985). “Determining soil hydraulic properties from one-step outflow experiments by parameter estimation. I: Theory and numerical studies.”Soil Sci. Soc. Am. J., 49, 1348–1354.
8.
Lenhard, R. J., Parker, J. C., and Mishra, S.(1989). “On the correspondence between Brooks-Corey and van Genuchten models.”J. Irrig. and Drain Engrg., ASCE, 115(4), 744–751.
9.
Mualem, Y.(1976). “A new model for predicting the hydraulic conductivity of unsaturated porous media.”Water Resour. Res., 12, 513–522.
10.
Parker, J. C., Kool, J. B., and van Genuchten, M. T.(1985). “Determining soil hydraulic properties from one-step outflow experiments by parameter identification. II: Experimental studies.”Soil Sci. Soc. Am. J., 49, 1354–1359.
11.
Parlange, J.-Y.(1975). “On solving the flow equation in unsaturated soils by optimization: Horizontal infiltration.”Soil Sci. Soc. Am. J., 39, 415–418.
12.
Philip, J. R.(1985). “Reply to `Comments on steady state infiltration from spherical cavities.”' Soil Sci. Soc. Am. J., 49, 788–789.
13.
Philip, J. R.(1990). “Inverse solution for one-dimensional infiltration, and the ratio A/K1.”Water Resour. Res., 26, 2023–2027.
14.
Russo, D.(1988). “Determining soil hydraulic properties by parameter estimation: On the selection of a model for the hydraulic properties.”Water Resour. Res., 24, 453–459.
15.
Russo, D., Bresler, E., Shani, U., and Parker, J. C.(1991). “Analyses of infiltration events in relation to determining soil hydraulic properties by inverse problem methodology.”Water Resour. Res., 27, 1361–1373.
16.
Shani, U., Hanks, R. J., Bresler, E., and Oliveiera, C. A. S.(1987). “A simple field method for estimating the hydraulic conductivity and matric potential-water content relations of soils.”Soil Sci. Soc. Am. J., 51, 298–302.
17.
Smettem, K. R. J., and Clothier, B. E. (1989). “Measuring unsaturated sorptivity and hydraulic conductivity using multiple disc permeameters.”J. Soil Sci., 563–568.
18.
van Dam, J. C., Stricker, J. N. M., and Droogers, P.(1992). “Inverse method for determining soil hydraulic functions from one-step outflow experiments.”Soil Sci. Soc. Am. J., 56, 1042–1050.
19.
van Genuchten, M. T.(1980). “A closed-form equation for predicting the hydraulic conductivity of unsaturated soils.”Soil Sci. Soc. Am. J., 44, 892–898.
20.
Warrick, A. W.(1993). “Inverse estimation of the soil hydraulic properties.”Soil Sci. Soc. Am. J., 57, 631.
21.
Warrick, A. W., and Broadbridge, P.(1992). “Sorptivity and macroscopic capillary length relationships.”Water Resour. Res., 28, 427–431.
22.
White, I., and Sully, M. J.(1987). “Macroscopic and microscopic capillary length and time scales from field infiltration.”Water Resour. Res., 23, 1514–1522.
23.
Wooding, R. A.(1968). “Steady infiltration from a shallow circular pond.”Water Resour. Res., 4, 1259–1273.
Information & Authors
Information
Published In
Copyright
Copyright © 1998 American Society of Civil Engineers.
History
Published online: Nov 1, 1998
Published in print: Nov 1998
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.