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

Experimentelle Rinnenerosionsforschung vs. Modellkonzepte – Quantifizierung der hydraulischen und erosiven Wirksamkeit von Rinnen
maximum sediment concentration in both runs was measured after 2:30 min at MP2, reaching
in run a 302 g L -1 , and 402 g L -1 in run b (figure 5).
Belerda: In this experiment, the average sediment concentration in the first run reached 28 g L
-1 at an average maximum flow velocity of 0.25 m s -1 . It should be noted that in this
experiment the flow velocity of the waterfront could not be measured. The waterfront of the
first run always shows the lowest flow velocity, so the 0.25 m s -1 mentioned here is too high.
In the second run, the average sediment concentration decreased to 16 g L -1 . The average
maximum flow velocity (waterfront included) reached 0.21 m s -1 . In the first run, the
maximum sediment concentration reached was 54 g L -1 at the waterfront at MP3. In the
second run, the waterfront at MP1 reached 29 g L -1 (figure 6).
The average detachment rate shows the highest values in most cases at the second measuring
point. In experiments Negratin b and Freila a, the highest values were reached at MP3, in
experiment Belerda b, the highest value was reached at MP1. The maximum detachment rates
also reach the highest values mostly at MP2, although Negratin b and Freila a reached them at
MP3, and Negratin a at MP1.
The highest average sediment flux values are reached at MP 3 for experiments Negratin a and
b and Freila a; at MP 2 for experiment Freila b, Salada a and b and Belerda a. Belerda b
reached the highest value at MP1. The maximum sediment flux values show the same trend,
except that in experiment Belerda a the highest value is not reached at MP2 but at MP3.
The transport capacity also shows a variable trend. In Negratin, the highest values were
reached at the first measuring point, in Freila at the second measuring point. In Salada, the
highest values were reached at the third measuring point. Only the maximum T C for the
second run was reached at the second measuring point. In the second Belerda run, the highest
values were reached at the third measuring point.
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