Premium
Prediction of unsaturated soil hydraulic conductivity with electrical conductivity
Author(s) -
Doussan Claude,
Ruy Stéphane
Publication year - 2009
Publication title -
water resources research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.863
H-Index - 217
eISSN - 1944-7973
pISSN - 0043-1397
DOI - 10.1029/2008wr007309
Subject(s) - electrical resistivity and conductivity , hydraulic conductivity , soil science , conductivity , soil water , water content , physical property , electrical resistivity tomography , spatial variability , robustness (evolution) , materials science , environmental science , geotechnical engineering , mathematics , geology , chemistry , physics , statistics , composite material , biochemistry , quantum mechanics , gene
Soil hydraulic conductivity ( K ) varies greatly with matric potential ( h ) and exhibits a high variability at the field scale. However, this key property for estimating water flux in soils is difficult to measure. In contrast, soil electrical conductivity ( σ ) is easier to measure and is influenced by the same parameters affecting K . We derive a simple relationship between σ and K ( h ) and test it against laboratory and literature data. Importantly, we show that parameters of this σ ‐ K ( h ) relationship can be completely determined with accessible measurements of saturated hydraulic conductivity, electrical conductivity of the soil solution, and clay content. This results in K ( h ) estimation with a RMSE ranging between 0.4 and 0.5 for log K , i.e., of the order of most experimental determinations of K . A further test of the σ ‐ K ( h ) relationship on the large UNSODA hydraulic database shows good agreement and the robustness of the relationship. Such a relation could be useful in the spatial monitoring of water fluxes at the field scale using electrical resistivity tomography if the σ ( h ) relationship can be obtained.