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

Experimentelle Rinnenerosionsforschung vs. Modellkonzepte – Quantifizierung der hydraulischen und erosiven Wirksamkeit von Rinnen
the 9 L min -1 – experiments ranged between 67.5 (75 % quartile) and 42.8 % (25 % quartile),
in the 250 L min -1 – experiments most RMEs were between 51.3 and 29.9 %. The highest
RMEs were 93.1 and 131.4 %, the lowest values were 9.5 and 26.7 %; the medians were 55.8
and 41.3 %. The RCs showed lower variations than the sediment concentrations, most RMEs
were between 48.3 and 13.9 %, the maximum value was 75.4 %, the minimum 0.3 % and the
median 20.8 %. The reason for the higher variations in sediment concentrations were “special
events” such as bank failure and headcut retreat. Such processes increased the sediment
concentration for a certain time period while the runoff stayed about constant.
Figure 2: Results of the rill experiments: Sediment concentrations of the 6 runs of the 3 rill
experiments with an inflow intensity of 9 L min -1 (A), sediment concentrations of the 8 runs
of the 4 rill experiments with an inflow intensity higher than 250 L min -1 (B), runoff
coefficients of all rill experiments (C), relative measurements errors of the sediment
concentrations (separated in experiments with an inflow intensity of 9 L min -1 and an inflow
intensity higher than 250 L min -1 ) and the runoff coefficients (D).
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