continued as in Phase III

Inverse modelling of soil hydraulic property patterns from non-invasive electrical measurements

Research Area:
Hydrogeophysics

Flow and transport properties of soils are decisively dependent on the structural and textural composition of the soil. A non-invasive method to obtain soil hydraulic property patterns would be highly useful, in particular to provide parameter input to subsurface flow models. The aim of this project is to understand, interpret, and validate the spatial distribution of spectral electrical properties obtained with electrical impedance tomography (EIT) in terms of soil hydraulic property patterns. Laboratory studies have already successfully related spectral electrical and hydraulic properties. Currently, we are validating these results using field infiltration experiments and newly developed broadband field EIT equipment.

Soil structural and textural heterogeneity can lead to significant variation of hydraulic properties in vertical and lateral direction. This hydraulic anisotropy may lead to electrical anisotropy. Therefore, we hypothesize that electrical anisotropy may provide additional information to characterize hydraulic systems. In particular, we are using laboratory experiments to analyze how small-scale structural heterogeneity and preferential flow processes affect electrical anisotropy. To allow imaging of electrical anisotropy, we are also developing forward and inverse modeling tools that incorporate anisotropic electrical conductivity. First field demonstrations have shown that many soils are electrically anisotropic, and we are in the process of interpreting this in a hydrological context.

Cooperation partner:
n/a