 |
| Titel |
Mechanisms of vegetation uprooting by flow in alluvial non-cohesive sediment |
| VerfasserIn |
K. Edmaier, P. Burlando, P. Perona |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1027-5606
|
| Digitales Dokument |
URL |
| Erschienen |
In: Hydrology and Earth System Sciences ; 15, no. 5 ; Nr. 15, no. 5 (2011-05-26), S.1615-1627 |
| Datensatznummer |
250012792
|
| Publikation (Nr.) |
 copernicus.org/hess-15-1615-2011.pdf |
|
|
|
|
|
| Zusammenfassung |
| The establishment of riparian pioneer vegetation is of crucial
importance within river restoration projects. After germination or
vegetative reproduction on river bars juvenile plants are often
exposed to mortality by uprooting caused by floods. At later
stages of root development vegetation uprooting by flow is seen to
occur as a consequence of a marked erosion gradually exposing the
root system and accordingly reducing the mechanical anchoring. How time
scales of flow-induced uprooting do depend on vegetation stages growing in alluvial
non-cohesive sediment is currently an open question that we conceptually address in this work.
After reviewing vegetation root issues in relation to
morphodynamic processes, we then propose two modelling mechanisms
(Type I and Type II), respectively concerning the uprooting time scales of
early germinated and of mature vegetation. Type I is a purely flow-induced drag mechanism,
which causes alone a nearly instantaneous uprooting when exceeding root
resistance. Type II arises as a combination of substantial
sediment erosion exposing the root system and resulting in a decreased
anchoring resistance, eventually degenerating into a Type I mechanism.
We support our conceptual models with some preliminary
experimental data and discuss the
importance of better understanding such mechanisms in order to
formulate sounding mathematical models that are suitable to plan
and to manage river restoration projects. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|