EGU2020-17727
https://doi.org/10.5194/egusphere-egu2020-17727
EGU General Assembly 2020
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Soil macropore-matrix mass exchange tracer experiments that account for sorption at macropore walls

Horst H. Gerke1, Jaromir Dusek2, Martin Leue1, Steffen Beck-Broichsitter1, Martina Sobotkova2, Michal Dohnal2, Tomas Vogel2, Michal Snehota2, Milena Cislerova2, Ruth H. Ellerbrock1, and Christoph Haas1
Horst H. Gerke et al.
  • 1Leibniz-Zentrum für Agrarlandschaftsforschung, ZALF, PB1-HYP, Müncheberg, Germany (hgerke@zalf.de)
  • 2Czech Technical University in Prague, Faculty of Civil Engineering, Prague, Czech Republic

The transfer of water and solutes between soil matrix and macropores controls preferential flow. Mass transfer depends on soil structural geometry and on properties of biopore walls and crack coatings that can differ from those of the matrix with respect to texture, organic matter, bulk density, and porosity. Agrochemicals and other solutes can react during transport along macropores, which has yet not been well-considered. The objective of this study was to study the specific effects of sorption on the reduction of mass exchange due to the effects of sorption at the macropore-matrix interface. Field and lab percolation experiments under unsaturated flow conditions were carried out with intact soil columns to simulate movement of bromide as a conservative and Brilliant Blue, iodide, and Na-Fluorescein as a reactive tracer. Sorption properties were determined separately for the biopore walls and crack coatings. The results suggest that preferential transport of reactive solutes depends even more strongly on the geometry and properties at flow paths surface than conservative solutes. If these properties can be determined, mass transfer coefficients in two-domain models can be related to soil structure and management.

How to cite: Gerke, H. H., Dusek, J., Leue, M., Beck-Broichsitter, S., Sobotkova, M., Dohnal, M., Vogel, T., Snehota, M., Cislerova, M., Ellerbrock, R. H., and Haas, C.: Soil macropore-matrix mass exchange tracer experiments that account for sorption at macropore walls, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17727, https://doi.org/10.5194/egusphere-egu2020-17727, 2020.

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