Characterization and Measurementof the Hydraulic Properties of
Unsaturated Porous MediaPart 1

Proceedings of the International Workshop on

Characterization and Measurement of the Hydraulic
Properties of Unsaturated Porous MediaRiverside, California
October 22-24, 1997

Edited by
M. Th. van Genuchten and F. J. Leij

U.S. Salinity Laboratory
USDA, ARS, Riverside, CA
L. Wu

Department of Environmental Sciences
University of California, Riverside, CA

USDA
U.S. Salinity Laboratory
Agricultural Research Service
U.S. Department of AgricultureRiverside, CA

Department ofEnvironmental Sciences
University of California
Riverside, CA

Proceedings of the International Workshop on Characterization and Measurement ofthe Hydraulic
Properties of Unsaturated Porous Media, Riverside, California, October 22-24, 1997, edited by
M. Th. van Genuchten, F. J. Leij, and L. Wu.
Published by the University of California, Riverside, CA 92521, USA
Copyright e 1999 by the Regents of the University of California on behalf of the Universityof California, Riverside
Any and all uses beyond the "fair use" provision of the law require written pennission from thepublisher or author(s); not applicable to contributions prepared by employees of the U.S. governmentas part of their official duties.

Preface
These Proceedings document presentations given at the International Workshop"Characterization and Measurement of the Hydraulic Properties of Unsaturated Porous Media,"held in Riverside, California, October 22-24, 1997. The workshop was organized to review
various aspects of water flow and solute transport in unsaturated porous media, particularly withrespect to the characterization and measurement of the unsaturated hydraulic properties (water
retention, hydraulic conductivity). Knowledge of the hydraulic properties is indispensable foraddressing many soil, hydrological, environmental, ecological and agricultural problems. They
are needed in nearly all basic and applied aspects of soil, water, nutrient, and salinity management
research (including precision agriculture), and serve as integrated indices for soil quality. They
are also needed in models for heat and mass transport near the soil surface to simulate the extent
and effects of regional and global climate change, and to interpret or improve the utility of
remotely sensed soil moisture data at a variety of spatial scales.
About 220 scientists and engineers from some 20 countries participated in the Workshop; they
included soil physicists, hydrologists, chemical and petroleum engineers, geologists, andagricultural engineers. Topics presented at the Workshop ranged from theoretical toapplication-oriented research, and from modeling to laboratory and field experimentation. The
multidisciplinary nature of the Workshop provided unique opportunities for the participants tointeract with each other, to appreciate issues and opportunities in porous media modeling andcharacterization, and to discover commonalities and differences between the various disciplines.
It is a pleasure and honor to acknowledge all those who contributed to the Workshop and these
Proceedings. First and foremost, the Workshop had the fortune of being sponsored by a large
number of governmental, professional and private organizations (see next page); their support
directly reflects the importance of the Workshop. Success of the Workshop would have been
impossible without the input from a large number of colleagues and friends, both here in Riversideand elsewhere. I thank all those who served on the Workshop Advisory Committee (see next page).
In Riverside, the help by Donna Cooney, Debbie Noordman and Carol Hansen of the Departmentof Environmental Sciences of the University of California, Riverside, proved to be indispensable.
Donna Cooney's insight and resourcefulness was especially critical. Roberta Cook provided
similar support from the U.S. Salinity Laboratory. Special thanks are due to all those involved in
the typing, editing and processing of the Workshop Abstracts and these Proceedings. They include
Walter Russell, Janice Neal, Louise DeHayes and, especially, Sharon Conditt, whose expertise,commitment and enthusiasm up until her untimely passing in October 1998 inspired us all. Dallas
Johnson and Kathy Chapman of Printing and Reprographics at UC-Riverside deserve much credit
for their superb job of printing these Proceedings.
I also must thank the many people of the U.S. Salinity Laboratory for their tireless help
before, during and after the workshop. These individuals include Bill Alves, Richard Austin, Fred
Ernst, Joan Fargerlund, Jack Jobes, Sondra Luther, Binayak Mohanty, Walter Russell, Marcel
Schaap, Pete Shouse, Jirka Simunek, Todd Skaggs, and Dong Wang, and of course co-editors
Feike Leij and Laosheng Wu. Finally, many thanks to the participants who found it worthwhile
to travel to Riverside from around the world, and who prepared first-rate contributions to these
Proceedings; it was their input and dedication that made the Workshop such a successful event.
Martinus Th. van Genuchten
Workshop Coordinator
Riverside, California
July, 1999

iii

Advisors and Sponsors
Workshop Advisory Committee
Michael Celia, Department of Civil Engineering and Operations Research, Princeton Univ.,
Princeton, NJ
Glendon W. Gee, Pacific Northwest Laboratory, Richland, WA
Russell S. Harmon, Army Research Office, DepartmentoftheArmy, Research Triangle Park, NC
Kishore K. Mohanty, Department of Chemical Engineering, University ofHouston, Houston, TX
Thomas J. Nicholson, U.S. Nuclear Regulatory Commission, Washington, DC
John Nimmo, U.S. Geological Survey, Menlo Park, CA
Berlie L. Schmidt, Cooperative State Research, Education and Extension Service, USDA,
Washington, DC
Terrence M. Sobecki, National Resources Conservation Service, USDA, Washington, DC
Ming-Ying Wei, National Aeronautics and Space Administration, Washington, DC
Ron Wilhelm, U.S. Environmental Protection Agency, Washington, DC
J. Henk M. Wosten, DLO Winand Staring Centre, Wageningen, the Netherlands

Co-Sponsoring Organizations
Agricultural Research Service, U.S. Department of Agriculture
Army Research Office, Department of the Army
Cooperative State Research, Education and Extension Service, U.S. Department of Agriculture
U.S. Environmental Protection Agency
U.S. Geological Survey
U.S. Nuclear Regulatory Commission

Corporate Sponsors
Campbell Scientific, Logan, UTCatena Verlag, Reiskirchen, Germany
Decagon Devices, Inc., Pullman, WA
Soil Measurement Systems, Tucson, AZ
Soilmoisture Equipment Corp., Santa Barbara, CA

iv

Contents Part 1
Characterization and Measurement of the Hydraulic Properties of Unsaturated
Porous Media .......................................................... 1
F J. Leij and M Th. van Genuchten

PORE-SCALE PHENOMENAThe Brooks-Corey Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
A. T. Corey and R. H. Brooks
Lognormal Distribution Model for Soil Hydraulic Properties ...................... 19
K. Kosugi
General Model of the HY._draulic Conductivity of Unsaturated Soils .................. 31
H. Hoffmann-Riem, M Th. van Genuchten, and H. Fluhler
A Model ofthc Relative Hydraulic Conductivity of Unsaturated Sandy Soils .......... 43
H. Ruan and T. H. Jllangasekare
Calculation of Fluid-Fluid and Fluid-Solid Interfacial Areas in Two-Fluid Porous ....... 53
Media as a Function of Capillary Pressure and Saturation
P. C. Reeves and M A. Celia
Dynamic Pore-Scale Network Model for Two-Phase Flow ........................ 63
T. Dijkstra, G. A. Bartelds, J. Bruining, and M Hassanizadeh
Pore-Scale Network Modeling of Soil Moisture Response to Temperature Changes ...... 71
L. A. Ferrand
Percolation Model for Interpretation of Moisture Retention Curves for ............... 81
Mono-Modal and Bi-Modal Soil Porous Systems
R. Rosslerova - Kodefova and V Kodes
Pore-Scale Soil Structure Models and Associated Hydraulic Properties ............... 93
E. Perrier, M Rieu, G. Sposito, and G~de Marsily
Simulation ofHydraulic Properties of Soil Using Pore-Network Models Based ........ 101
on Morphological Data
H. ..J. Vogel and K. RothSurface Energy and Imbibition into Triangular Pores ........................... 109
N R. Morrow and X Xie
Measurement oflnterfacial Surface Areas for Two-Phase Flow in Porous Media
from PVI Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
C. D. Montemagno and Y Mav

----------------------------------

Multiphase Transport Properties from Network Modeling ....................... 133
V Mani and K. K. Mohanty
Modeling Nonwetting Phase Permeability Using Analytical and Network Models ...... 145
U Fischer, M A. Celia, H. F/Uhler, and M Th. van Genuchten
Percolation Methods to Derive Relative Permeabilities and the Enhancement Factor .... 155
for Polymer/Water Displacement of Oil Products
G. A. Barte Ids and J Bruining
Multifluid Hydraulic Properties for Fractional Wettability Porous Media ............ 165
S. A. Bradford, L. M Abriola, and F J Leij
Modeling Relationships Among Relative Permeabilities, Fluid Saturations, and . . . . . . . 179
Capillary Pressures in Mixed-Wet Porous Media: Theory
R .J Lenhard and M Oostrom
Modeling Relations Among Relative Permeabilities, Fluid Saturations, and Capillary ... 189
Pressure in Mixed Wet Porous Media: Model Testing and Application
to Oil-Water Systems
M Oostrom, R. J Lenhard, M De/shad, and S. D. Robertson
Accurate Estimates of Multiphase Flow Functions ............................. 199
A. T. Watson and J-E. Nortvedt
Determination of Capillary Pressure - Saturation - Permeability Relations ........... 207
for Nonwetting Fluids in Water Wet Porous MediaJ H. Dane, C. Hofstee, M Oostrom, H. H. Liu, and A. T. Corey
Experimental Investigations of Multiphase Flow Systems ........................ 217
0. Kemmesies, R. Giese, and L. Luckner
Impact of Organic Compound Chemistry on Capillary Pressure Relationships of Sands . 229
A. H. Demond, K. F Hayes, D. L. Lord, F Desai, and A. Salehzadeh

DIRECT METHODS

Innovations in Two-Phase Measurements of Hydraulic Properties .................. 241
G. W Gee and A. L. Ward
Laboratory
Direct Hydraulic Conductivity Measurements for Evaluating Approximate ........... 271
and Indirect Determinations
C. Dirksen
Comparison of Laboratory and Field Methods for Determining the Quasi-Saturated .... 279
Hydraulic Conductivity of Soils
B. FaybishenkoviUnsaturated Hydraulic Parameters Determined from Direct and Indirect Methods ...... 293

L. E. Flint, D. B. Hudson, and A. L. Flint
Determining the Unsaturated Soil Hydraulic Conductivity in the Entire Suction
Range Using a Two-Step Method .......................................... 303

M J. Santos, M C. Gonfaives and L. S. Pereira
Soil-Dependent Flux Boundary Conditions for Wind's Evaporation Method .......... 313

T. Gabele and R. HochWind's Evaporation Method: Experimental Equipment and Error Analysis ........... 323

P. Bertuzzi, D. Mohrath, L. Bruck/er, J. C. Gaudu, and M Bour/etThree Automated Laboratory Systems for Determining the ....................... 329
Hydraulic Properties of Soils
H G. M van den Elsen, J. Stolte, and G. Veerman
Development oflntemet Tools for Calculation and Prediction of Soil ............... 341
Hydraulic Properties

M Mizoguchi
Profile-Scale Simulation of Water Flow: A Software Package to Visualize ........... 349
and Estimate Effects of Soil Hydraulic Properties
E. Perrier, P. Garnier, and Ch. Leclerc
Estimation of Hydraulic Parameters Under Constant Flux Condition ................ 355
Using Multipurpose TDR Probes

B. C. Si, R. G. Kachanoski, Z. F Zhang, G. W Parkin, and D. E. Elrick
Saturation Profiles from Dielectric (Frequency Domain Reflectometry) .............. 363
Measurements in Porous Media

B. L. Nguyen, J. Bruining, and E. Slob
Estimating Soil Hydraulic Properties In Situ Using a Line Source ................. 373
Z. F. Zhang, R. G. Kachanoski, and G. W. Parkin
Measurement Resolution of the Dual-Probe Heat-Pulse Technique ................. 381
Y Song, M B. Kirkham, J. M Ham, and G. J. Kluitenberg
Reducing Measurement Errors for Selected Soil Water Sensors ................... 387

J. Bilskie
Magnetic Resonance Imaging and.Preferential Flow in Soils ...................... 397
M Cislerova, J. Votrubova, T. Vogel, M H. G. Amin, and L .D. Hall
Probing Pore Characteristics in a Sandy Soil with Nuclear Magnetic Resonance ....... 413

Z. R. Hinedi and A. C. Changvii

Case Studies
Fingered Flow: The Role of the Induction Zone Below the Soil Surface and .......... 423
the Capillary Fringe
H. Cho and G. H. de Rooij
Rapid Determination of Constitutive Relations with Fingered Flow ................ 433
D.A. DiCarlo, T. W.J Bauters, C.JG. Darnault, T.S. Steenhuis, and J-Y. Parlange
Determining the Hydraulic Properties of Swelling Soils by Parameter Estimation ...... 441
P. V. Garnier and M Rieu
Influence of Mechanical and Hydraulic Stresses on Hydraulic Properties ............ 449
of Swelling Soils
Th. Baumgart/ and R. Horn
Dual Gamma-Ray Scanner and Instantaneous Profile Method for Swelling ........... 459
Unsaturated Materials
R. Angulo.Jaramillo, M Vauclin, R. Haverkamp, and P. Gerard-Marchant
Hysteretic Hydraulic Properties of a Coarse Sand Horticultural Substrate ............ 467
M Heinen and P. A. C. Raats
Hydraulic Properties of Root Zone Substrates Used in Greenhouse Horticulture ....... 477
W. Otten, P. A. C. Raats, and P. Kabat
Impact of Tillage and Field Traffic Induced Variability of Soil Hydraulic Properties .... 489
on Unsaturated Conductivity and Water Balance Calculations
C. H. Roth, K. L. Bristow, J Brunotte, M Fack/am-Moniak, and G. Wessolek
Effect of Temperature on Hydraulic Conductivity .............................. 497
H. Stoffregen, G. Wesso/ek, M Renger, and R. Plagge
Clay Dispersion and Hydraulic Conductivity of Low and High Swelling Smectites ..... 507
Under Sodic Conditions
N. Toride
Temporal Changes in Unsaturated Hydraulic Properties of Sand due to ............. 517
Clay Migration and Water Quality
M Moutier, E. Degand, and L. W. De Backer

Use of The Cone Permeameter Method to Determine Soil Hydraulic Properties ........ 527
R. Kodefova, MM Gribb, and J Simmek
Soil Hydraulic Conductivity and Retention Curves from Tension Infiltrometer ........ 541
and Laboratory Data
S. R. Evett, F H. Peters, 0. R. Jones, and P. W. Unger

viii

Recent Advances in Using Ring Infiltrometers and TDR to Measure ................ 553
Hydraulic Properties of Unsaturated Soils
G. W. Parkin, D. E. Elrick and W. D. Reynolds
Accuracy of Soil Hydraulic Property Estimation Using Infiltrometers Having ......... 563
Different Disk Sizes
D. Wang, S. R. Yates, and M Th. van Genuchten
Tension Disk Infiltrometry to Determine the Near-Saturated Hydraulic Conductivity ... 571
of Organic and Coarse-textured Soils on Granites
A. V. Auzet, R. Angulo-Jaramillo, H. Damiron, M Pluyms, B. Ambroise,
and M Vauclin
Unsaturated Soil Hydraulic Properties in the Region Near Saturation ............... 579
S. D. Logsdon
Measurements of Soil Hydraulic Properties with a Tension Disk Inflltrometer ......... 587
F Moreno, L. Andreu, J E. Fernandez, and F Pelegrln
Evaluation of Soil Hydraulic Properties in BOREAS ........................... 593
R. H. Cuenca and S. F Kelly
Ground-Based Investigation of Soil Moisture Variability Within Remote Sensing ...... 603
Footprints During SGP97: First Results
J S. Famiglietti, J A. Devereaux, C. Laymon, T. Tsegaye, P. R. Houser,
T. J Jackson, S. T. Graham, M Rodell, and B. P. Mohanty
The Spatial-Temporal Structure of U.S. Southern Great Plains Soil Moisture: ........ 609
A Preliminary Analysis of SGP97 Observations
P.R. Houser
Field Scale Characterization ofa Heterogeneous, Moderately Deep Vadose Zone: ...... 621
The Kearney Research Site
T. Harter, K Heeren, G. Weissmann, W. R. Horwath, and J W. Hopmans
Chloride and Tritium Concentrations in a Thick Unsaturated Zone Underlying ....... : 631
an Intermittent Stream in the Mojave Desert, Southern California
J lzbicki, R. L. Michel, and P. Martin

INVERSE METHODS

Review oflnverse Estimation of Soil Hydraulic Properties ....................... 643
J W. Hopmans and J Simmek
State-of-the-Art in Inverse Modeling of Inflow/Outflow Experiments ............... 661
W. Durner, B. Schultze, and T. Zurmiihlix

Evaluation of a Laboratory Inverse Method to Determine Soil Hydraulic ............ 683
Functions from Evaporation Experiments
N Romano
Description of Soil Hydraulic Properties Near Saturation from the Point of View ...... 693
of Inverse Modeling
T. Vogel, M Nakhaei, and M Cislerova
SUFI: An Inverse Approach for Conditional Parameter Estimation ................. 705
K. C. Abbaspour, R. Schulin, and M Th. van Genuchten
Soil Hydraulic Properties from Laboratory Evaporation Experiments by ............. 713
Parameter Estimation
J. Simmek, 0. Wendroth, and M Th. van Genuchten
Using a Multi-Step Soil-Water Extraction Technique for In-Situ Estimation .......... 725
of Soil Hydraulic Properties
M Inoue, J.Simmek, J. W. Hopmans, and V. C/ausnitzer
Soil Hydraulic Properties Determined from Evaporation and Tension ............... 737
Infiltration Experiments and Their Use for Modeling Field Moisture Status
0. Wendroth, and J. Simtlnek
Determination of Hydraulic Properties Using Tension lnfiltrometer Data and ......... 749
Inverse Optimization
D. Jacques, J. Feyen, and D. Mal/ants
Parameter Estimation of Unsaturated Soil Hydraulic Properties from Transient ....... 761
Outflow Experiments Using Genetic Algorithms
Y Takeshita and I. Kohno
Inverse Estimation of Hydraulic Parameters by Using Simulated Annealing .......... 769
and Downhill Simplex Method
L. Pan and L. Wu
Identification of the Hydraulic Properties ofa Layered Silt Loam .................. 783
J. A. de Vos, J. Simtlnek, P.A. C. Roats, and R. A. Feddes
Inverse Method to Estimate Soil Hydraulic Parameters from Field Measurementsof Ponded Infiltration
K. Bohne, D. Radcliffe, G. Wessolek, and S. Zachariasx. . . . . 799

Contents Part 2
INVERSE METHODS

Detennination of Parameters for Flexible Hydraulic Functions by Inverse Modeling .... 817
W Durner, E. Priesack, H. ...!. Vogel, and T. Zurmuhl
Hydraulic Properties of a Macroporous Soil ................................ 831
B. P. Mohanty
Measurement and Prediction of Near-Saturated Hydraulic Conductivity ............. 839
for Use in Dual-Porosity Models
N Jarvis, I. Messing, M H. Larsson, and L. Zavattaro
Simple Characterization of Non-Equilibrium Water Flow in Structured Soils ......... 851
P. J. Ross and K. R. J. Smettem
Water Potential to Depths of30 Meters in Fractured Basalt and Sedimentary Interbeds .. 855
J. B. Sisson and J. M Hubbell
What Does a Tensiometer Measure in Fractured Rock? ......................... 867
S. Finsterle and B. Faybishenko
Dynamic Nonequilibrium During Unsaturated Water Flow ....................... 877
B. Schultze, 0. Ippisch, B. Huwe, and W Durner
Flow Rate Dependence of Hydraulic Properties of Unsaturated Porous Media ......... 893
D. Wildenschild and J. W Hopmans
Transient Effects on the Hydraulic Properties of Porous Media .................... 905
R. Plagge, P. Htiupl, and M Renger
Dependence of Apparent Unsaturated Parameters on Experiment Type and ........... 913
Estimation Method
K. J. Hollenbeck and K. H. Jensen

INDIRECT METHODS

Predicting Soil-Water Retention and Hydraulic Conductivity from Textural .......... 923
and Structural lnfonnation
J. R. Nimmo
Relationship Between Particle-Size Distribution and Soil Water Retention ........... 931
L. M Arya, F J. Leij, and M Th. van Genuchten
Physically-Based Pedotransfer Function for Estimating Water Retention ............. 947
Curve Shape Parameters
F Bouraoui, R. Haverkamp, C. Zammit, and J.-Y. Parlangexi

Estimating Soil Hydraulic Conductivity from Soil Particle-Size Distribution .......... 959
A. Kravchenko and R. Zhang
Development of Hydraulic Pedotransfer Functions from Soil Morphological Features ... 967
H. S. Lin, K. J Mcinnes, L. P. Wilding, and C. T. Hallmark
Performance of Available Pedotransfer Functions for Predicting the Water Retention ... 981
Properties of French Soils
G. Bastet, A. Bruand, M Voltz, M Bornand. and P. Quetin
Pedotransfer Functions for Soil Water Retention Characteristics ................... 993
T. Mayr, N Jarvis, and C. Simota
Improving Prediction Accuracy of Soil Water Retention with Concomitant Variables ... 999
K. Rajkai, S. Kabos, and P. E. Jansson
Calculating Hydraulic Properties of Unsaturated Soils Using Hydrological .......... 1005
Constants and Atterberg Limits
E. V Shein, A. K. Guber, and A. V Dembovetsky
Estimating Soil Water Retention Using the Gregson One-Parameter Function ........ 1011
R. D. Williams, L. R. Ahuja, and W J Rawls
Characterization of Soil Structure in Relation to Saturated Hydraulic Conductivity . . . . 1019
D. Gimenez, W J Rawls, Ya. A. Pachepsky, and J P. C. Watt
Brooks-Corey Pore Size Distribution Index to Estimate Saturated ................. 1029
Conductivity from Effective Porosity
D.J Timlin, L.R. Ahuja, Ya.A. Pachepsky, R.D. Williams, D. Gimenez, and WJ Rawls
Autoregressive Procedure to Predict Hydraulic Conductivity: .................... 1037
Measured and Predicted Results
M Renger. H. Stoffregen, J Klocke, M Fack/am, G. Wessolek, C. H. Roth,and R. Plagge
Calibration of Unsaturated Hydraulic Conductivity Functions .................... 1047
for Gravity-Drainage Experiments
D. A. V Eckhardt and R. J Wagenet
Andersson's and van Genuchten's Equations for Predicting the ................... 1061
Hydraulic Conductivity of Unsaturated Soils
M Jauhiainen and T. Karvonen
Comparison of Indirect and Instantaneous Profile Methods for Estimating . . . . . . . . . . 1071
the Unsaturated Hydraulic Conductivity
K. A. Mc Vay and D. E. Radcliffe
Models for Unsaturated Soil Hydraulic Conductivity .......................... 1077
A.M Zeiliguer, A. Mermoud, and S. Tamarixii

Analysis of Multi-Step Outflow Data and Pedotransfer Functions to Characterise ..... 1089
Soil Water Flow and Solute Transport at Different Scales
H. Vereecken and R. Kaiser
Obtaining Hydraulic Properties for Soil Water Balance Models: .................. 1103
Some Pedotransfer Functions for Tropical Australia
K. L. Bristow, K. R. J. Smettem, P. J. Ross, E. J. Ford, C. H. Roth, and K. Verburg
Estimation of Soil Property Functions and Their Application in Transport Modeling . . . 1121
E. Priesack, W Sinowski, and R. Stenger
Comparison of Three Parameter Conversion Methods Between van Genuchten ....... 1131
and Brooks-Corey Functions for Water-Balance Predictions
Q. L. Ma, J. E. Hook, and L. R. Ahuja
Strategy for Determining Hydraulic Properties of Australian Soils Using
Direct Measurements and Pedotransfer Functions ............................. 1143
H. Cresswell, N. McKenzie, and Z. Paydar
Functional Comparison of Methods for Obtaining Soil Hydraulic Properties ......... 1161
W J Bond, H. P. Cresswell, K. Verburg, and N. J McKenzie
Direct UFA Measurements of the Unsaturated Hydraulic Conductivity; Comparisons . . 1173
to van Genuchten/Mualem Estimations, and Applications to Recharge Mappingin Arid Regions
J L. Conca, D. G. Levitt, P. R. Heller, T. J Mockler, and M J Sully
Estimation of Hydraulic Parameters for Portuguese Soils
M C. Gon~alves, V. V. Almeida, and L. S. Pereira

1199

Estimating Soil Water Retention with Several Soil Models . . . . . . . . . . . . . . . . . . . . . . 1211
A.M Zeiliguer
Pedotransfer Functions with Interdependency of Hydraulic Parameters ............. 1225
0. Tietje
Bootstrap-Neural Network Approach to Predict Soil Hydraulic Parameters .......... 1237
M G. Schaap, F J Leif, and M T. van Genuchten
Using Artificial Neural Networks to Develop Pedotransfer ...................... 1251
Functions of Soil Hydraulic Properties
S. Tamari and J H. M Wosten
Estimation of Soil Water Retention Using Two Models Based on Regression ........ 1261
Analysis and an Artificial Neural Network
A. Krenn
The UNSODA Unsaturated Soil Hydraulic Database .......................... 1269
F J Leif, W J Alves, M Th. van Genuchten, and J R. Williams

xiii

The Development and Use of the HYPRES Database in Europe .................. 1283
A. Lilly, J. H M W(Jsten, A. Nemes, and C. Le Bas
Estimation of Hydraulic Properties of an Unsaturated Soil Using a ................ 1295
Knowledge-Based System
M D. Fredlund, G. W. Wilson, and D.G. Fredlund
Evaluation of Different Techniques for Interpolation of the Particle-Size Distribution .. 1307
A. Nemes, J. H M W(Jsten, A. Lilly, and J. H Oude Voshaar
Near-Surface Permeability in Soil Survey: Assuming Use-Invariance .............. 1317
for a Use-Dependent Property
R. B. Grossman and D. S. Harms
Soil Information Resources for Environmental Modeling at Regional Scales . . . . . . . . . 1327
D. A. Miller
Development of STATSGO Pedotransfer Functions Using a Group . . . . . . . . . . . . . . . 1333
Method of Data Handling
W. J. Rawls, Ya Pachepsky, D. Gimenez, and R. Elliott
Estimating and Testing a Database of Soil Hydraulic Properties for . . . . . . . . . . . . . . . 1343
Simulating Water Flow in a Pleistocene Landscape
U Schindler, J. Steidl, F Eulenstein, and L. Muller

FLOW AND TRANSPORT

Deterministic Prediction of Unsaturated Flow in Randomly Heterogeneous .......... 1351
Soils Under Uncertainty Without Upscaling
S. P. Neuman, D. M Tartakovsky, C. Filippone, 0. Amir, and Z. Lu
Determination of Field-Scale Hydraulic Parameters Using a Nonlinear Filter ........ 1367
with Quantitative Spatial Analysis
F Ungaro, A. T. Cahill, M B. Par/ange, D. R. Nielsen, and M Mata
A Site Characterization Method for the Vadose Zone
T.-C. J. Yeh

1377

Upscaling Constitutive Relationships in Unsaturated Heterogeneous Media: ......... 1381
Numerical Experiments
A.J. Desbarats
Conditional Simulation and Upscaling of Soil Hydraulic Properties ............... 1391
M L. Rockhold, C. J Murray, and M J Fayer
Dependence of the Hydraulic Conductivity on Space and Time Scales .............. 1403
A.G. Huntxiv

Scaling Behavior of the Near-Saturated Hydraulic Conductivity .................. 1415
B. P. Mohanty and P. J. Shouse
Infiltration Characteristics : From Column to Parcel to Hill Slope. A Physical and .... 1425
Stochastic Theory for Spatial, Temporal and Process Integration
H J. Morel-Seytoux
Characterization of Soil Hydraulic Parameter Uncertainty ...................... 1439
P. D. Meyer, G. W. Gee, M L. Rockhold, and M G. Schaap
Restriction of Hydraulic Parameters for Unsatchem Model ...................... 1453
P.J. Vaughan and D.L. Suarez
Estimation of Parameters of Log-Unsaturated Conductivity Covariance by Inversion .. 1459
of Solute Transport Data
D. Russo
Impact of Source Size and Horizontal Correlation Scale on Solute Transport ........ 1475
During Unsaturated Hysteretic Flow
R. Mitchell and A. S. Mayer
Solute Transport Estimated by Field- and Laboratory-Determined Hydraulic Parameters 1485
R. Kasteel, J. Forrer and H. Fluhler
Relating Saturated and Unsaturated Hydraulic Conductivity to Gas Diffusivity and ... 1495
the Campbell Water Retention Model
0. H. Jacobsen, T. G. Poulsen, P. Moldrup, and P. Schjonning
Unsaturated Flow in a Two-Layered Closed Soil System ....................... 1509
J. Chikushi
Using the HYDRUS-lD and HYDRUS-2D Codes for Estimating Unsaturated ....... 1523
Soil Hydraulic and Solute Transport Parameters
J. Simiilek, M Th. van Genuchten, and M Sejna
Field-Scale Modeling Study to Characterize Hydraulic Properties for Water, ........ 1537
Air and Heat Flow in the Unsaturated Zone of Yucca MountainY. S. Wu, S. Finsterle, and G. S. Bodvarsson
Characterization ofNon-Isothermal Mass Transfer in Unsaturated Soils ............ 1549
A. M Globus
Prediction of Coupled Heat, Air and Moisture Transfer in Porous Building Materials . . 1561
J. Grunewald, R. Plagge, and P. Haupl
Group Picture ....................................................... 1573
Address List ........................................................ 1579
Author Index ....................................................... , 1581
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