Hydrology and Earth System Sciences
www.hydrol-earth-syst-sci.net
1027-5606
1607-7938
8
1
2004
10.5194/hess-8-2-2004
http://www.hydrol-earth-syst-sci.net/8/2/2004/
http://www.hydrol-earth-syst-sci.net/8/2/2004/hess-8-2-2004.html
http://www.hydrol-earth-syst-sci.net/8/2/2004/hess-8-2-2004.pdf
2
7
0000-00-00
Direct measurement of the soil water retention curve using X-ray absorption
A. Bayer
H.-J. Vogel
K. Roth
Institute of Environmental Physics, INF 229, University of Heidelberg, D-69120 Heidelberg, Germany
E-mail for corresponding author: andreas.bayer@iup.uni-heidelberg.de
X-ray absorption measurements have been explored as a fast experimental
approach to determine soil hydraulic properties and to study rapid dynamic processes. As
examples, the pressure-saturation relation θ(Ψ) for a uniform sand column has been
considered as has capillary rise in an initially dry sintered glass column.
The θ(Ψ)-relation is in reasonable agreement with that obtained by inverting a
traditional multi-step outflow experiment. Monitoring the initial phase of capillary rise
reveals behaviour that deviates qualitatively from the single-phase, local-equilibrium regime
described by Richards’ equation.</p>
<b>
<p style="line-height: 20px;"><b>Keywords: </b>X-ray absorption, soil hydraulic properties, soil water dynamics,
Richards’ equation