Published online 3 October 2006
Published in Vadose Zone J 5:1093-1109 (2006)
DOI: 10.2136/vzj2005.0104
© 2006 Soil Science Society of America
677 S. Segoe Rd., Madison, WI 53711 USA
A Field Application of the Scaled-Predictive Method for Unsaturated Soil
M. J. Thomassona,*,
P. J. Wierengab and
T. P. A. Ferréc
a Errol L. Montgomery & Associates, Inc., 1550 East Prince Rd., Tucson, AZ 85719
b Dep. of Soil, Water and Environmental Science, Univ. of Arizona, Tucson, AZ
c Dep. of Hydrology and Water Resources, Univ. of Arizona, Tucson, AZ

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Fig. 1. Schematic of experimental plot showing locations where data was collected and access culverts.
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Fig. 2. Model initial conditions and observed initial conditions. The circles and squares represent the mean observed soil water contents for Exp. 1 and 2, respectively. The solid line represents the interpolated soil water contents used in the model (HYDRUS).
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Fig. 3. Percentage sand, silt, and clay composition for the NP #413 location.
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Fig. 4. Soil water content vs. time for three soil depths and two sets of hydraulic property parameters. Circles are the measured soil water contents; dashed lines represent tension obtained with tensiometers. Solid lines represent predicted soil water contents. Experiment 1, unadjusted models.
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Fig. 5. Measured (circles) and predicted soil water contents (solid lines) for Days 18, 26, and 42. Experiment 1, unadjusted models.
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Fig. 6. Hydraulic conductivity vs. water content. Symbols are the field-calculated hydraulic conductivity values for 50- to 300-cm depths in 50 cm intervals; (A) the dashed line is based on a laboratory-derived value of 44.6 cm d1 for Ks, the solid lines represent the adjusted hydraulic conductivity relationships and (B) the dashed lines are based on a neural network values of 37.09 and 67.83 cm d1 for Ks, the solid lines represent the adjusted hydraulic conductivity relationships.
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Fig. 7. Soil water content vs. time for three soil depths and two sets of hydraulic property parameters. Circles are the measured soil water contents; dashed lines represent tension obtained with tensiometers. Solid lines represent predicted soil water contents. Experiment 1, adjusted models.
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Fig. 8. Measured (circles) and predicted soil water contents (solid and dashed lines) for Days 18, 26, and 42. Experiment 1, adjusted models.
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Fig. 9. Measured (circles) and predicted soil water contents (solid and dashed lines) for Days 18, 26, and 42. Experiment 1, inverse (adjusted) model.
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Fig. 10. Soil water content vs. time for three soil depths for the inverse model. Circles are the measured soil water contents; dashed lines represent tension obtained with tensiometers. Solid lines represent predicted soil water contents. Experiment 1, inverse (adjusted) model.
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Fig. 11. Soil water content vs. time for three soil depths and two sets of hydraulic property parameters. Circles are the measured soil water contents; dashed lines represent tension obtained with tensiometers. Solid lines represent predicted soil water contents from the models. Experiment 2, adjusted models.
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Fig. 12. Soil water content vs. time for three soil depths for the NN + S-P model. Circles are the measured soil water contents; dashed lines represent tension obtained with tensiometers. Solid lines represent predicted soil water contents from the models. Experiment 2, adjusted model.
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Fig. 13. Soil water content vs. time for three soil depths and two sets of hydraulic property parameters. Circles are the measured water contents; dashed lines represent tension obtained with tensiometers. Solid lines represent predicted soil water contents. Experiment 2, unadjusted models.
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Fig. 14. Soil water content vs. time for three soil depths and two sets of hydraulic property parameters. Circles represent the measured soil water contents; dashed lines represent tension obtained with tensiometers. Solid lines represent predicted soil water content. Experiment 2, adjusted models, upper soil layer not scaled.
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Fig. 15. Measured (circles) and predicted soil water contents (solid and dashed lines) for Days 7, 33, and 37. Experiment 2, adjusted models.
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Fig. 16. Measured (circles) and predicted soil water contents (solid and dashed lines) for Days 7, 33, and 37. Experiment 2, inverse (adjusted) model.
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Copyright © 2006 by the Soil Science Society of America.