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

Experimentelle Rinnenerosionsforschung vs. Modellkonzepte – Quantifizierung der hydraulischen und erosiven Wirksamkeit von Rinnen
becomes evident once more. On the relatively flat surface in experiments 3a and b, the mean
translocation distances of the sub segments is nearly identical in experiment 3a (8.4 cm, 8.3
cm) and a little higher in sub segment 1a in experiment 3b (8.7 cm, 5.6 cm). On the steeper
11° slope in experiment 3c, the mean translocation distance in the downslope-forward sub
segment (1b) is significantly higher (14.1 cm, 22.9 cm). The difference in experiment 3c can
probably be explained by the high overlap of the driving forces of initial kicking impulse and
gravity in sub segment 1b. While we assume that 1a contains some rock fragments that were
initially kicked in upslope direction, fragments that ended in 1b have likely been kicked in
downslope direction by the goats right away. In that case, impulse and gravity would meet
best in 1b, leading to the highest mean translocation distance (22.9 cm) here.
The mean net downslope translocation rates for experiments 3a, b and c are 2.6 cm, 1.5 cm
and 6.6 cm. Again, slope appears to be a dominating factor and explains why the highest
distance is recorded in experiment 3c. The low net mean downslope translocation rate of 1.5
cm in experiment 3b is caused by the relatively high proportion of unmoved stones.
3.4 Loosening quantity
Figure 7: Loosening rate of fine material on a highly crusted plain surface
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