User menu

Accès à distance ? S'identifier sur le proxy UCLouvain

Analysis of air-launched ground-penetrating radar techniques to measure the soil surface water content

Primary tabs

Lambot, Sébastien [UCL] Weihermuller, Lutz Huisman, Johan A. Vereecken, Harry Vanclooster, Marnik [UCL] Slob, Evert C.

We analyze the common surface reflection and full-wave inversion methods to retrieve the soil surface dielectric permittivity and correlated water content from air-launched ground-penetrating radar (GPR) measurements. In the full-wave approach, antenna effects are filtered out from the raw radar data in the frequency domain, and full-wave inversion is performed in the time domain, on a time window focused on the surface reflection. Synthetic experiments are performed to investigate the most critical hypotheses on which both techniques rely, namely, the negligible effects of the soil electric conductivity (s) and layering. In the frequency range 1-2 GHz we show that for sigma>0.1 Sm-1, significant errors are made on the estimated parameters, e. g., an absolute error of 0.10 in water content may be observed for sigma=1 Sm-1. This threshold is more stringent with decreasing frequency. Contrasting surface layering may proportionally lead to significant errors when the thickness of the surface layer is close to one fourth the wavelength in the medium, which corresponds to the depth resolution. Absolute errors may be >0.10 in water content for large contrasts. Yet we show that full-wave inversion presents valuable advantages compared to the common surface reflection method. First, filtering antenna effects may prevent absolute errors >0.04 in water content, depending of the antenna height. Second, the critical reference measurements above a perfect electric conductor (PEC) are not required, and the height of the antenna does not need to be known a priori. This averts absolute errors of 0.02-0.09 in water content when antenna height differences of 1-5 cm occur between the soil and the PEC. A laboratory experiment is finally presented to analyze the stability of the estimates with respect to actual measurement and modeling errors. While the conditions were particularly well suited for applying the common reflection method, better results were obtained using full-wave inversion.

Document type Article de périodique (Journal article) – Article de recherche
Publication date 2006
Language Anglais
Journal information "Water Resources Research" - Vol. 42, no. 11 (2006)
Peer reviewed yes
Publisher Amer Geophysical Union (Washington)
issn 0043-1397
e-issn 1944-7973
Publication status Publié
Affiliation UCL - SST/ELI/ELIE - Environmental Sciences
Links
  1. al Hagrey, Muller, GPR study of pore water content and salinity in sand, 10.1046/j.1365-2478.2000.00180.x
  2. Annan A. P., 10.1023/a:1020657129590
  3. Boithias, Radio Wave Propagation (1987)
  4. Chanzy A., Tarussov A., Bonn F., Judge A., Soil Water Content Determination Using a Digital Ground-Penetrating Radar, 10.2136/sssaj1996.03615995006000050005x
  5. Davis, Methods of Soil Analysis, part 4, Physical Methods, 446 (2002)
  6. Dobson M., Ulaby Fawwaz, Active Microwave Soil Moisture Research, 10.1109/tgrs.1986.289585
  7. Du, Proceedings of the Fifth International Conference on Ground Penetrating Radar, 1241 (1994)
  8. Famiglietti J. S., Devereaux J. A., Laymon C. A., Tsegaye T., Houser P. R., Jackson T. J., Graham S. T., Rodell M., van Oevelen P. J., Ground-based investigation of soil moisture variability within remote sensing footprints During the Southern Great Plains 1997 (SGP97) Hydrology Experiment, 10.1029/1999wr900047
  9. Galagedara L. W., Parkin G. W., Redman J. D., An analysis of the ground-penetrating radar direct ground wave method for soil water content measurement, 10.1002/hyp.1351
  10. Galagedara L.W., Parkin G.W., Redman J.D., von Bertoldi P., Endres A.L., Field studies of the GPR ground wave method for estimating soil water content during irrigation and drainage, 10.1016/j.jhydrol.2004.06.031
  11. Galagedara L. W., Redman J. D., Parkin G. W., Annan A. P., Endres A. L., Numerical Modeling of GPR to Determine the Direct Ground Wave Sampling Depth, 10.2136/vzj2004.0143
  12. Grote K., Hubbard S., Rubin Y., Field-scale estimation of volumetric water content using ground-penetrating radar ground wave techniques : WATER CONTENT ESTIMATES USING GPR GROUND WAVES, 10.1029/2003wr002045
  13. Huisman J.A., Sperl C., Bouten W., Verstraten J.M., Soil water content measurements at different scales: accuracy of time domain reflectometry and ground-penetrating radar, 10.1016/s0022-1694(01)00336-5
  14. Huisman J.A., Snepvangers J.J.J.C., Bouten W., Heuvelink G.B.M., Mapping spatial variation in surface soil water content: comparison of ground-penetrating radar and time domain reflectometry, 10.1016/s0022-1694(02)00239-1
  15. Huisman J. A., Hubbard S. S., Redman J. D., Annan A. P., Measuring Soil Water Content with Ground Penetrating Radar, 10.2136/vzj2003.4760
  16. JACKSON T. J., SCHMUGGE J., ENGMAN E. T., Remote sensing applications to hydrology: soil moisture, 10.1080/02626669609491523
  17. Lagarias Jeffrey C., Reeds James A., Wright Margaret H., Wright Paul E., Convergence Properties of the Nelder--Mead Simplex Method in Low Dimensions, 10.1137/s1052623496303470
  18. Lambot S., Antoine M., van den Bosch I., Slob E. C., Vanclooster M., Electromagnetic Inversion of GPR Signals and Subsequent Hydrodynamic Inversion to Estimate Effective Vadose Zone Hydraulic Properties, 10.2136/vzj2004.1072
  19. Lambot S., Rhebergen J., van den Bosch I., Slob E. C., Vanclooster M., Measuring the Soil Water Content Profile of a Sandy Soil with an Off-Ground Monostatic Ground Penetrating Radar, 10.2136/vzj2004.1063
  20. Lambot S., Slob E.C., van den Bosch I., Stockbroeckx B., Vanclooster M., Modeling of ground-penetrating Radar for accurate characterization of subsurface electric properties, 10.1109/tgrs.2004.834800
  21. Lambot Sébastien, Bosch Idesbald van den, Stockbroeckx Benoit, Druyts Pascal, Vanclooster Marnik, Slob Evert, Frequency Dependence of the Soil Electromagnetic Properties Derived from Ground-Penetrating Radar Signal Inversion, 10.1007/s11220-005-4228-x
  22. Lambot, Proceedings of the 3rd International Workshop on Advanced Ground Penetrating Radar, 113 (2005)
  23. Lambot Sébastien, Antoine Michaël, Vanclooster Marnik, Slob Evert C., Effect of soil roughness on the inversion of off-ground monostatic GPR signal for noninvasive quantification of soil properties : EFFECT OF SOIL ROUGHNESS ON GPR SIGNAL, 10.1029/2005wr004416
  24. Ledieu J., De Ridder P., De Clerck P., Dautrebande S., A method of measuring soil moisture by time-domain reflectometry, 10.1016/0022-1694(86)90097-1
  25. Merz Bruno, Bárdossy András, Effects of spatial variability on the rainfall runoff process in a small loess catchment, 10.1016/s0022-1694(98)00213-3
  26. Michalski K.A., Mosig J.R., Multilayered media Green's functions in integral equation formulations, 10.1109/8.558666
  27. Redman, Proc. SPIE Int. Soc. Opt. Eng., 4758, 156 (2002)
  28. Serbin Guy, Or Dani, Near-Surface Soil Water Content Measurements Using Horn Antenna Radar, 10.2136/vzj2003.5000
  29. Serbin G., Or D., Ground-penetrating radar measurement of soil water content dynamics using a suspended horn antenna, 10.1109/tgrs.2004.831693
  30. Serbin Guy, Or Dani, Ground-penetrating radar measurement of crop and surface water content dynamics, 10.1016/j.rse.2005.01.018
  31. Ulaby, Microwave Remote Sensing: Active and Passive, vol. III, From Theory to Applications (1986)
  32. Warnick Karl F, Chew Weng Cho, Numerical simulation methods for rough surface scattering, 10.1088/0959-7174/11/1/201
  33. Yelf, Proceedings of the Tenth International Conference on Ground Penetrating Radar, 279 (2004)
Bibliographic reference Lambot, Sébastien ; Weihermuller, Lutz ; Huisman, Johan A. ; Vereecken, Harry ; Vanclooster, Marnik ; et. al. Analysis of air-launched ground-penetrating radar techniques to measure the soil surface water content. In: Water Resources Research, Vol. 42, no. 11 (2006)
Permanent URL http://hdl.handle.net/2078.1/38129