 |
| Titel |
The influence of grid resolution on the prediction of natural and road-related shallow landslides |
| VerfasserIn |
D. Penna, M. Borga, G. T. Aronica, G. Brigandí, P. Tarolli |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1027-5606
|
| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 18, no. 6 ; Nr. 18, no. 6 (2014-06-10), S.2127-2139 |
| Datensatznummer |
250120380
|
| Publikation (Nr.) |
 copernicus.org/hess-18-2127-2014.pdf |
|
|
|
|
|
| Zusammenfassung |
| This work evaluates the predictive power of the quasi-dynamic shallow
landslide model QD-SLaM to simulate shallow landslide locations in a
small-scale Mediterranean landscape, namely, the lower portion (2.6 km2)
of the Giampilieri catchment, located in Sicily (Italy). The catchment was
impacted by a sequence of high-intensity storms over the years 2007–2009,
resulting in widespread landsliding, with a total landslide initiation area
amounting to 2.6% of the basin area. The effect of high-resolution digital
terrain models (DTMs) on the quality of model predictions is tested by
considering four DTM resolutions: 2, 4, 10 and 20 m. Moreover, the impact of
the dense forest road network on the model performance is evaluated by
separately considering road-related landslides and natural landslides. The
landslide model does not incorporate the description of road-related failures
and is applied without calibration of the model parameters. The model
predictive power is shown to be DTM-resolution dependent. Use of coarser
resolution has a smoothing effect on terrain attributes, with local slope
angles decreasing and contributing areas becoming larger. The percentage of
watershed area represented by the model as unconditionally unstable (i.e.
failing even without the addition of water from precipitation) ranges between
6.3% at 20 m DTM and 13.8% at 2 m DTM, showing an overestimation of the
mapped landslide area. We consider this prediction as an indication for
likely failing sites in future storms rather than areas proved stable during
previous storms. When assessed over the sample of mapped non-road-related
landslides, better model performances are reported for 4 and 10 m DTM
resolution, thus highlighting the fact that higher DTM resolution does not
necessarily mean better model performances. Model performances over
road-related failures are lower than for the natural cases, and slightly
increase with decreasing DTM resolution. These findings indicate that to
realize the full potential of high-resolution topography, more extensive work
is needed aiming more specifically to identify the extent of the artificial
structures and their impact on shallow landsliding processes. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|