Morphological structures on the pedon scale, like earthworm channels, cracks and soil
aggregates, significantly influence flow processes during infiltration. Cracks or earthworm
channels in a low permeable matrix, for example, lead to macropore flow with low interaction
(water exchange between macropores and matrix). The same structures in a highly permeable
matrix lead to macropore flow with high interaction, whereas a spatially heterogeneous soil
matrix (aggregation or texture) induce heterogeneous matrix flow. If the infiltrating water
is coloured with a dye tracer, characteristic dye patterns result from these different flow
At different sites, sprinkling experiments on plots of 3 m2 with dyed water were performed
and the resultant dye-covered vertical and horizontal soil sections at different locations
and depths were prepared and photographed. The photographed sections were then objectively
classified into stained areas, non-stained areas and visible macropores (>1 mm2) by means
of image analysis techniques. The characteristic dye pattern of different flow processes
could be recognised in the classified soil sections using a new identification method.
The combination of vertical and horizontal sections enables the detection of relevant
morphological structures and allows for a consistent identification of flow processes
in soil profiles.