Stefan Wirtz Vom Fachbereich VI (Geographie/Geowissenschaften ...

Experimentelle Rinnenerosionsforschung vs. Modellkonzepte – Quantifizierung der hydraulischen und erosiven Wirksamkeit von Rinnen
Fig. 2: The 4 tested rills: top left Negratin; top right Freila; bottom left Salada; bottom right
Belerda
Rill experiment
The rill experiments consist of two runs: first the rill is tested under field conditions (“dry”);
in a second run, about 15 min later, the same rill is tested under “wet” conditions.
With a motor driven pump, a constant discharge of 9 L min -1 is maintained for 8 minutes,
resulting in a total water inflow of 72 L. To avoid mobilization of soil particles by the
inflowing water at the starting point of the experiment, the inflow velocity and pressure are
reduced with an inflow device, which allows the water to enter the rill as a light stream (Wirtz
et al., 2010).
The flow velocity within the rill is characterized in three steps: the travel time of the
waterfront and of two different colour tracers is measured for every meter using a
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