IMAGE-ANALYSIS FOR DETERMINATION OF DYE TRACER CONCENTRATIONS IN SANDCOLUMNS

Dye tracers can be used to visualize how paths in soils, We used digit al image analysis to determine the spatial distribution of dye concent rations in a quartz sand column, Color slides and near-infrared black- and-white photographs mere taken from a sand column that was cut in ha lves longitudinally after a point-source dye infiltration experiment. In a separate calibration experiment, sand samples were prepared with known water content and dye concentration. Photographs of such sample arrays were used as training areas for image analysis, Image analysis is a viable way for obtaining a high spatial resolution of tracer conc entrations and provides a quantitative basis for describing different solute mixing regimes.