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

Experimentelle Rinnenerosionsforschung vs. Modellkonzepte – Quantifizierung der hydraulischen und erosiven Wirksamkeit von Rinnen
m 2 would be necessary to generate the experimental runoff in the rill. Due to the considerably
lower RC in Belerda (51 %), the contributing area was estimated to be 27 m 2 (Table 2).
Rill hydraulics
The descriptors of the rills’ hydraulics are summarized in Table 3.
After the given flow length, only 19 L water reach in the first run in Salada the end of the
tested rill part. The highest value (59 L) is measured in the second run in the Belerda
experiment.
The highest maximum runoff intensity was measured in the first run in the Belerda
experiment (0.15 L s -1 ), the lowest maximum runoff intensity in the first run of the Salada
experiment (0.07 L s -1 ).
The relationship between inflow intensity and runoff intensity shows the highest value in the
first Belerda run, here the inflow and the runoff intensity are equal. The lowest value is
measured in Salada, run a (0.47).
The highest runoff coefficient is measured in Belerda run b, here 82 % of the inflow water
reach the runoff measuring point. In the first Salada run, only 27 % reach the end of the tested
rill part.
The runoff-length-factor shows its lowest value in Salada run a (3.96 m) the highest value is
measured in Freila run a (13.71 m). In all experiments, the second run shows higher values
than the first run but in the second run in Freila, there are no data available because of
technical problems.
The runoff at the rill’s end starts in the second run in the Belerda experiment still after 70 sec.,
in the first run of the Freila experiment, the water reaches the rill’s end after 175 sec. After
593 sec., the runoff ends in the first run of the Salada experiment, in the first run of the Salada
experiment, the runoff has finished after 866 sec. The runoff shows the longest duration in the
first run in Negratin (700 sec.), the fastest runoff wave has been noticed in the first run in
Freila (88 sec.).
The relationship between runoff duration and inflow duration shows the highest value in
Negratin run a (1.46), the lowest value in Salada run a (0.92).
Average flow velocities show the highest values in Freila run b (Front), Negratin run a
(Tracer 1) and Salada run b (Tracer 2), the lowest values in Freila and Salada run a (Front),
and Belerda run b (Tracer 1 and Tracer 2). The maximum flow velocities show the highest
values in Freila run b (Front) and Negratin run a (Tracer 1 and Tracer 2), the lowest values are
measured in Freila run a (Front), Freila run b (Tracer 1) and Belerda run b (Tracer 2).
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