We use a Ground Penetrating Radar (GPR) to monitor the surface soil moisture in agricultural fields in the framework of the HYDRASENS project and other research activities in the Environmental Sciences group of the Earth and Life Institute. Several field campaigns were done since 2008, from which surface soil moisture maps are displayed in this webmap.


The developed GPR system in UCL is based on a vector network analyzer emulating the radar waves and on off-ground ultra wideband horn antennas. Inversion of the GPR signal permits to retrieve the soil electromagnetic properties, i.e., the dielectric permittivity and the electrical conductivity. More details can be found in Lambot et al., 2004 and Minet et al., 2011. For hydrology and soil science applications, the GPR-inverted dielectric permittivity can then be translated into soil moisture using the Topp's petrophysical relationship.

Webmap development

This webmap is based on the OpenLayers JavaScript library. Open-source softwares only were used to make this webmap, including QGIS, MapServer and GIMP.


  • S. Lambot, E. C. Slob, I. van den Bosch, B. Stockbroeckx, and M. Vanclooster.
    Modeling of ground-penetrating radar for accurate characterization of subsurface electric properties. IEEE Transactions on Geoscience and Remote Sensing, 42, 2555-2568, 2004.
  • J. Minet, A. Wahyudi, P. Bogaert, M. Vanclooster, and S. Lambot.
    Mapping shallow soil moisture profiles at the field scale using full-waveform inversion of ground penetrating radar data. Geoderma, 161, 225-237, 2011.

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