RESEARCH INTERESTS

Soil hydraulic and soil electrical properties, pedotransfer functions, hydrological and energy cycles in ecosystems, soil carbon, soil dielectric properties, pore-scale modeling and environmental instrumentation.

Web links:
Rosetta: A program to estimate soil hydraulic parameters
Research Site (work in progress)

EMPLOYMENT

2006-present Department of Soil, Water and Environmental Science, University of Arizona.

2000-2006, Assistant/Associate Professional Research Scientist, University of California, Riverside.

2005, Letter of Appointment, Desert Research Institute, Las Vegas, Nevada.

1996-2006, Cooperative Employee, George E. Brown, Jr. Salinity Laboratory (USDA-ARS), Riverside, CA.

1996-2000, Postdoctoral Researcher. University of California, Riverside.

REFEREED JOURNAL ARTICLES

1. Bouten W., M.G. Schaap, D.J. Bakker, and J.M. Verstraten, 1992. Modelling soil water dynamics in a forested ecosystem: A site specific evaluation. Hydrological Processes, 6:435-444.

2. Bouten W., M.G. Schaap, J. Aerts, and A.W.M Vermetten, 1996. Monitoring and modelling canopy water storage amounts in support of atmospheric deposition studies. Journal of Hydrology, 181:305-321.

3. Schaap, M.G., and W. Bouten, 1996. Modeling water retention curves of sandy soils using neural networks. Water Resources Research, 32:3033-3040.

4. Schaap, M.G. and W. Bouten, 1997. Forest floor evaporation in a dense Douglas fir stand. Journal of Hydrology, 201:367-383.

5. Schaap, M.G., W. Bouten, and J.M. Verstraten, 1997. Forest Floor water content dynamics of a Douglas fir stand. Journal of Hydrology, 193:97-113.

6. Schaap, M.G., L. De Lange and T.J. Heimovaara. 1997. TDR calibration of organic forest floor media. Soil Technology, 11:205-217.

7. Schaap, M.G., F.J. Leij, and M.Th.van Genuchten, 1998. Neural network analysis for hierarchical prediction of soil water retention and saturated hydraulic conductivity. Soil Sci. Soc. Am. J., 62:847-855.

8. Schaap, M.G., and F.J. Leij, 1998. Using Neural Networks to predict soil water retention and soil hydraulic conductivity. Soil & Tillage Research, 47:37-42.

9. Schaap, M.G., and F.J. Leij, 1998. Database related accuracy and uncertainty of pedotransfer functions, Soil Science, 163:765-779.

10. ?imūnek, J., R Angulo-Jaramillo, M.G. Schaap, J.P. Vandervaere, and M.Th. van Genuchten, 1998. Using an inverse method to estimate the hydraulic properties of crusted soils from tension disc infiltrometer data. Geoderma, 86:61-81.

11. Lebron, I., M.G. Schaap, and D.L. Suarez, 1999. Saturated Hydraulic conductivity prediction from microscopic pore geometry measurements and neural network analysis, Water Resour. Res., 35:3149-3158.

12. Leij, F.J., M. G. Schaap, and E. Priesack, 2000. Three-dimensional transport from persistent solute sources modeled with Green’s functions. Contaminant Hydrology, 41:155-173.

13. Schaap, M.G., and F.J. Leij. 2000. Improved Prediction of Unsaturated Hydraulic Conductivity with the Mualem-van Genuchten Model, Soil Sci. Soc. Am. J., 64:843-851.

14. Dekker, S.C., W. Bouten and M.G. Schaap, 2001. Use of artificial neural networks to improve predictions of a deterministic forest transpiration model. Journal of Hydrology, 246:197-208.

15. Johnson, C.A., M.G. Schaap, and K.C. Abbaspour. 2001. Model comparison of flow through a municipal solid waste incinerator ash landfill. Journal of Hydrology, 243:55-72.

16. Goncalves, M.C., F.J. Leij, and M.G. Schaap, 2001. Pedotransfer functions for solute transport parameters. European Journal of Soil Science, 52:563-574.

17. Schaap, M.G., F.J. Leij, and M. Th. van Genuchten, 2001. Rosetta: a computer program for estimating soil hydraulic parameters with hierarchical pedotransfer functions. Journal of Hydrology, 251:163-176.

18. Nemes, A. M. G. Schaap, F. J. Leij and J. H. M. Wösten, 2001. Unsaturated Soil hydraulic Database UNSODA V2.0 for Windows. Journal of Hydrology, 251:151-162.

19. Schaap, M.G., and I. Lebron, 2001. Using Microscope Observations of Thin Sections to Estimate Soil Permeability with the Kozeny-Carman Equation. Journal of Hydrology, 251:186-201.

20. Lebron I., D.L. Suarez, and M.G. Schaap, 2002. Soil pore size and geometry as a result of aggregate-size distribution and chemical composition. Soil Science, 167:165-172.

21. Raat K.J., G.P.J. Draaijers, M.G. Schaap, A. Tietema, and J.M. Verstraten, 2002. Spatial variability of throughfall water and chemistry and forest floor water content in a Douglas fir forest stand. Hydrology & Earth System Sciences, 6:363-374.

22. Robinson, D.A., M.G. Schaap, S.B. Jones, S.P. Friedman, and C.M.K. Gardner, 2003. Considerations for improving the accuracy of permittivity measurement using time domain reflectometry. Soil Sci. Soc. Am. J., 67:62-70.

23. Nemes, A., M.G. Schaap, and J.H.M. Wösten, 2003. Functional evaluation of pedotransfer functions derived from different scales of data collection. Soil Sci. Soc. Am. J., 67:1093-1102.

24. Schaap, M.G., D.A. Robinson, S.P. Friedman, A. Lazar, 2003. Measurement and Modeling of TDR signal propagation through layered dielectric media. Soil Sci. Soc. Am. J., 67:1113-1121.

25. Kelleners, T.J., R.W.O. Soppe, D.A. Robinson, M.G. Schaap, J.E. Ayars, and T.H. Skaggs, 2004. Calibration of capacitance probe sensors using electric circuit theory. Soil Sci. Soc. Am. J., 68:430-439.

26. F.J. Leij, N. Romano, M.G. Schaap, A. Coppola, and M. Palladino, 2004. Topographical attributes to predict soil hydraulic properties along a hillslope transect. Water Resour Res., Vol. 40, No. 2, W02407 10.1029/2002WR001641.

27. Schaap. M.G., A. Nemes, and M. Th. Van Genuchten, 2004. Comparison of Models for Indirect Estimation of Water Retention and Available Water in Surface Soils. Vadose Zone Journal, 3:1455-1463.

28. D.A. Robinson, D.A., M.G. Schaap, D. Or, and S. B. Jones, 2005.Modeling of ‘Effective Frequency’ of TDR measurements in Dispersive, Non-Conductive Dielectrics. Water Resour Res. Vol. 41 W02007 10.1029/2004WR003816.

29. Børgesen, C.D., and M.G. Schaap, 2005. Point and Parameter Pedotransfer Functions for Water Retention Predictions for Danish Soils. Geoderma, 127:154-167.

30. Schaap, M.G., and M.Th. van Genuchten, 2006. A Modified Mualem-van Genuchten formulation for improved description of the hydraulic conductivity near saturation, Vadose Zone Journal 5: 27-34.

31. Børgesen, C.D., O.H. Jacobsen, S. Hansen, M.G. Schaap, 2006. Soil hydraulic properties near saturation: an improved conductivity model. J. of Hydrol. 324 (1-4): 40-50

32. Faust, A.E., P.A. Ferré, M.G. Schaap, A.C. Hinnell, 2006. Can basin-scale recharge be estimated reasonably with water balance models? Vadose Zone Journal, 5: 850-855.

33. Børgesen, C.D., B.V. Iversen, O.H. Jacobsen, M.G. Schaap. 2007. Pedotransfer functions estimating soil hydraulic properties using different soil parameters. Hydrological Processes (accepted, Feb. 2007, approx. 10 pages).

34. Ye, M., M.G. Schaap, R. Khaleel, and J. Zhu, 2006. Simulation of Field Injection Experiments in a Layered Formation Using Geostatistical Methods and Artificial Neural Network. Water Resour. Res. (Accepted, February 2007, approx. 15 pages).

35. Schaap, M.G, M.L. Porter, B.S.B. Christensen, and D. Wildenschild, 2006.Comparison of pressure-saturation characteristics derived from computed tomography and lattice Boltzmann simulations,. (Accepted Water Resour. Res. . 2007, approx 15 pages).

36. Huang, H. M.G. Schaap, D.T. Thorne, M.C. Sukop. 2007. A Priori Determination of Contact Angles in Shan-and- Chen-type Multi-component Multiphase Lattice Boltzmann Models. (Accepted Phys Rev E., Sep. 2007, approx 8 pages)

BOOK CHAPTERS

1. Geijn, S.C., P. Dijkstra, A. Gorissen, A.H.C.M. Schapendonk, K. Kramer, G.M.J. Mohren, F. Berendse, Th. Jetten, C. de Kovel., W. Takken., H. Lankreijer, A.W.L. Veen, W. Bouten, M.G. Schaap, J. Rozema, and A. Visser, 1995. Assessment report on NRP subtheme "Effects of climate change on terrestrial ecosystems". In: Zwerver S., R.S.A.R. van Rompaey, M.T.J. Kok and M.M. Berk (eds): Climate change research: evaluation and policy implications. Elsevier Science, Amsterdam, the Netherlands.

2. Schaap, M.G, F.J. Leij and M. Th. van Genuchten, 2000. Estimation of the Soil Hydraulic Properties. In: B.B. looney and R.W. Falta (eds.), Vadose Zone Science and Technology Solutions, vol. 1, pp. 501-509, Battelle Press, Columbus, OH.

3. F.J. Leij, M.G. Schaap, and L.M.Arya, 2002. Indirect methods. In: Methods of Soil Analysis: Part 4-Physical Methods (Eds J.H. Dane and G.C Topp), 36p, Soil Science Society of America, 677 South Segoe Road, Madison, WI.

4. Van Dam, R. L., E.H. Van Den Berg, M.G. Schaap, L.H. Broekema, W. and Schlager, 2003. Radar reflections from sedimentary structures in the vadose zone. In: Ground penetrating radar in sediments: applications and interpretation (Ed. by C. S. Bristow & H. M. Jol), Geological Society Special Publication, Geological Society, London, pp 257-273.

5. Pachepsky, Y, and M.G. Schaap, 2004. Data mining and exploration techniques. In: Pachepsky, Y. and W.J. Rawls (Eds.), Development of Pedotransfer Functions in Soil Hydrology, pp 21-32, Elsevier, Amsterdam, and the Netherlands.

6. Schaap, M.G., 2004. Accuracy and uncertainty in PTF predictions. In: Pachepsky, Y. and W.J. Rawls (Eds.), Development of Pedotransfer Functions in Soil Hydrology, pp 33-46, Elsevier, Amsterdam, and the Netherlands.

7. Schaap, M.G., 2004. Graphic user interfaces for pedotransfer functions. In: Pachepsky, Y. and W.J. Rawls (Eds.), Development of Pedotransfer Functions in Soil Hydrology, pp 349-356, Elsevier, Amsterdam, and the Netherlands.

8. Schaap, M.G., 2005. Models for Indirect Estimation of Soil Hydraulic Properties, In: Anderson M.G., Encyclopedia of Hydrological Sciences, Wiley, p1145-1150.

Book Reviews

Schaap, M.G. Percolation Theory for Flow in Porous Media, Soil Sci Soc Am. J., 2006. 70: 1036-a-1037-a

CONFERENCE PROCEEDINGS

1. Meyer, P.D, G.W. Gee, M.L. Rockhold, M.G. Schaap, 1999. Characterization of soil hydraulic parameter uncertainty. In: van Genuchten, M.Th., F.J. Leij, and L. Wu (eds), Proc. Int. Workshop, Characterization and Measurements of the Hydraulic Properties of Unsaturated Porous Media, pp 1439-1451, University of California, Riverside, CA.

2. Schaap, M.G., F.J. Leij and M. Th. van Genuchten, 1999. A bootstrap-neural network approach to predict soil hydraulic parameters. In: van Genuchten, M.Th., F.J. Leij, and L. Wu (eds), Proc. Int. Workshop, Characterization and Measurements of the Hydraulic Properties of Unsaturated Porous Media, pp 1237-1250, University of California, Riverside, CA.

3. van Genuchten, M. Th., M.G. Schaap, B.P. Mohanty, J. ?imūnek, and F.J. Leij, 1999. Modeling flow and transport processes at the local scale. In: J. Feyen and K. Wiyo (eds.). 1999. Modelling of transport processes in soils at various scales in space and time. Proc. Int. Workshop of EurAgEng’s Field of Interest on Soil and Water, November 24-26, 1999, Leuven, Belgium, pp 23-45, Wageningen Pers, Wageningen, The Netherlands.

4. Schaap, M.G. and M.Th. van Genuchten, 2001. Rosetta: a hierarchical pedotransfer function model to predict the unsaturated soil hydraulic properties from soil texture and related data. In: Proceedings of the conference Modflow 2001 and other Modeling Odysseys, September 11-14, 2001, Colorado School of Mines, Golden, Colorado, pp 571-577.

5. Nemes, A., M.G. Schaap, and J. H. M. Wösten, 2002. Validation of international scale soil hydraulic pedotransfer functions for national scale applications. International Union of Soil Science Meeting, Bangkok, Thailand. (10 pages, published on CD-ROM)

6. Schaap, M.G., F.J. Leij, and M.Th. van Genuchten, 2002. Estimating the unsaturated soil hydraulic properties using a hierarchical set of pedotransfer functions. In: Proc. Second Federal Interagency Modeling Conference, “Hydrologic Modeling for the 21st Century”, Las Vegas, NV, July 28-August 1, 2002, CD Rom, Session 1B, 11p, U.S. Geological Survey, Subcommittee on Hydrology, Denver, CO.

7. van Genuchten, M. Th., and M.G. Schaap, 2004. Improved description of the hydraulic properties of unsaturated structured media near saturation. In: B. Faybishenko and P. A. Witherspoon (eds.), Proc. 2nd Int. Symp. on "Dynamics of Fluids in Fractured Rock", Feb. 10-12, 2004, pp. 255-259, LBNL-54275, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA.

8. Schaap, M.G., and I. Lebron, 2004. An evaluation of permeability of statistically reconstructed three-dimensional pore structures with Lattice Boltzmann simulations. In: C.T. Miller, M.W. Farthing, W. G. Gray, and G.F. Pinder, Computational Methods in Water Resources, Proceedings of the XV'th International Conference on Computational Methods in Water Resources (CMWR XV), June 13-17, 2004, Chapel Hill, NC, USA, Elsevier, Amsterdam, the Netherlands.

9. van Genuchten, M. Th., J. Simunek, M. G. Schaap and T. H. Skaggs, 2004. Unsaturated zone parameter estimation using the HYDRUS and Rosetta software packages. In: T. J. Nicholson, J. E. Babendreier, P. D. Meyer, S. Mohanty, B. B. Hicks, and G. H. Leavesley (eds.), Proc. Int. Workshop "Uncertainty, Sensitivity, and Parameter Estimation for Multimedia Environmental Modeling", August 19-21, 2003, Rockville, MD, NUREG/CP-0187, pp. 41-43, U.S Nuclear Regulatory Commission, Rockville, MD.

10. Schaap, M.G., and J.H.M. Hendrickx, 2005. Dielectric relaxation effects on permittivity of surface soils. In: Harmon, R.S., J. Thomas Broach, John H. Holloway, Jr., 2005, Proceedings of SPIE Volume 5794: Detection and Remediation Technologies for Mines and Minelike Targets X, pp135-143, The International Society for Optical Engineering (SPIE), Bellingham, WA, USA.

11. M. G. Buehler, R. C. Anderson, S. Seshadri, and M. G. Schaap, 2005. Prospecting for In Situ Resources on the Moon and Mars using Wheel-Based Sensors. IEEE Aerospace Conference Proceedings 2005, Paper Number 1573.

12. Dissly R. W., M.G. Buehler, M.G. Schaap, D. Nicks, G.J Taylor, R. Castano, D. Suarez, 2004. Autonomous In-Situ Resources Prospector. “Space Resources Roundtable VI” LPI Contribution No. 1224. Proceedings of the conference held November 1-3, 2004, at the Colorado School of Mines, Golden Colorado, USA. Sponsored by the Colorado School of Mines, the Lunar and Planetary Institute and the Space Resources Roundtable, Inc. Published by the Lunar and Planetary Institute, Houston, TX USA, p.17.

13. Anderson, R.C, M. Buehler, S. Seshadri, G. Kuhlman, and M.G. Schaap, 2005. Dielectric constant measurements for characterizing lunar soils. Paper published by the Lunar and Planetary Science Conference, March 14?18, 2005, publication available at: http://www.lpi.usra.edu/meetings/lpsc2005/pdf/1969.pdf

14. Seshadri, S., M. Buehler, R.C. Anderson, G. Kuhlman, D. Keymeulen, I.W. Cheung, and M.G. Schaap, 2005. Applicability of electrical and electroanalytical techniques to detect water and characterize the geochemistry of undisturbed planetary Paper published by the Lunar and Planetary Science Conference, March 14?18, 2005, publication available at: http://www.lpi.usra.edu/meetings/lpsc2005/pdf/2195.pdf

15. Schaap, M.G., A. Nemes, J.H.M. Wösten, 2005. Functional evaluation of different scale soil hydraulic pedotransfer functions for Hungarian soils. In: Simon L. (ed.), Proceedings of the International Scientific Conference "Innovation and Utility in the Visegrad Fours". Volume 1. Environmental Management and Environmental Protection. October 13-15, 2005. Nyíregyháza, Hungary. Continent-Ph.(publisher), Nyíregyháza. pp. 103-108. ISBN:963 86918 0 8 Ö, ISBN:963 86918 2 4. pp.195-200.

16. Buehler, M.G. H. Bostic, K. B. Chin, T. McCann, D. Keymeulen, R. C. Anderson, S. Seshadri, and M. G. Schaap, 2006. Electrical Properties Cup (EPC) for Characterizing Water Content of Martian and Lunar Soils, IEEE Aerospace Conference Proceedings 2006, Paper Number: 1400, March 4-11, Big Sky, Montana, 0-7803-9546-8/06/2006.

17. Schaap, M.G. B.S.B. Christensen, M.L. Porter, D. Wildenschild, Linking Experimental Capillary Pressure-Saturation Data with Lattice Boltzmann Simulations. Proceedings of the XVI'th International Conference on Computational Methods in Water Resources (CMWR XVI), June 19-22, 2006, Copenhagen, Denmark. http://proceedings.cmwr-xvi.org/contribAuthorDisplay.py?authorId=schaap+marcel+mschaap%40ucr.edu&confId=a051

18. Porter, M.L., M.G. Schaap, and D. Wildenschild, 2006. Dr. Dorthe Wildenschild Dynamic Effects in Oil/Water and Air/Water Capillary Pressure-Saturation Curves: Experiments and Lattice-Boltzmann Simulations. Proceedings of the XV'th International Conference on Computational Methods in Water Resources (CMWR XV), June 19-22, 2006, Copenhagen, Denmark. http://proceedings.cmwr-xvi.org/contributionDisplay.py?contribId=120&sessionId=9&confId=a051