Observation of Reactive Transport in Soil Columns with Positron Emission Tomography (GeoPET)

Here we investigate reactive transport in soils with GeoPET as quantitative spatiotemporal molecular imaging method. As PET directly yields tracer concentrations, the data can be utilised for parameterization and validation of reactive transport computer models.

Artificial soil columns (sand/silt/clay/Goethit, length 90 mm, diameter 40 mm) have been prepared under CO₂-atmosphere. Four different experiments on one and the same soil column are shown as motion pictures from the GeoPET-observations:

1) Injection of water, labelled with [¹⁸F]KF, into the CO₂-saturated column

2) Conservative transport of [¹⁸F]KF solution through the water-saturated column

3) Injection of the reactive tracer [⁶⁴Cu]Cu(MCPA)₂ into the unconditioned water-saturated column

4) Injection of the reactive tracer [⁶⁴Cu]Cu(MCPA)₂ into the preconditioned column.

The study was supported within the framework of the priority program “Biogeochemical Interfaces in Soil” by the German Science Foundation (DFG SPP 1315: KE508/19 and LI872/5).

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Stoll, M., Kulenkampff, J., Gründig, M., Lippmann-Pipke, J., and Kersten, M.: Molecular positron emission tomography imaging of Cu mobility enhanced by the herbicide 4-chloro-2-methylphenoxy-acetic acid in a soil column, submitted

Lippold, H., Karimzadeh L., Kulenkampff, J. Wissmeier, L., Stuhlfauth, C., Stoll, M., Lippmann-Pipke, L.: Effect of pH on the mobility of the herbicide MCPA in a goethite-sand matrix: 1D and 2D reactive transport modelling, to be submitted