Mountain drainage basins are complex systems due to the variety of active geomorphic processes,their interactions at different spatial/temporal scales, and the history of the landscape in terms of climate and tectonic activity. geomorphic coupling. These systems encompass hillslopes dominated by diffusive surface erosion and/or landsliding, steep confined channels dominated by debris flows, and purely alluvial channels flowing along major valley floors where fluvial transport prevails. In this context, the overall process of sediment transfer across landscape components and the associated disturbance-cascade are poorly understood, including the relative importance of one geomorphic process over the others at the watershed scale. In places where hillslopes and channels are well-connected, transport processes overlap, hence strongly interact via geomorphic coupling. The term coupling is used in geomorphology (e.g.,Brunsden and Thornes, 1979; Caine and Swanson, 1989) to indicate the degree of connectivity between hillslope and fluvial processes. Coupled systems exhibit direct colluvial-alluvial interaction, as opposed to decoupled (or buffered) systems, where colluvial sediment inputs do not reach the channel network. Evaluation of degree of coupling is critical to drainage basin sediment dynamics as it controls (i) sediment and process-disturbance cascades, and (ii) in what proportion hillslope denudation rate contributes to drainage basin sediment storage and fluvial sediment yield respectively (e.g., Roberts and Church, 1986; Reid and Dunne, 1996). In geomorphology, the importance of coupling between channels and adjacent hillslopes has been long acknowledged (e.g., Korup, 2005; Fryirs et al., 2007). However, relatively little work has attempted to assess its role in a systematic way. Partly because only very few empirical studies (both field-based and remotely-sensed) have tried to combine hillslopes and channelized landscape components (Benda et al., 1998). In this lecture, we will (i) evaluate how hillslope-channel connectivity can affect channel-reach morphology, channel geometry, and sediment transport potential through published examples and unpublished datasets; (ii) propose future research needs on the topic.

Brardinoni, F. (2010). Hillslope-channel connectivity. In NGF Abstracts and Proceedings of the Geological Society of Norway.

Hillslope-channel connectivity

BRARDINONI, FRANCESCO
2010

Abstract

Mountain drainage basins are complex systems due to the variety of active geomorphic processes,their interactions at different spatial/temporal scales, and the history of the landscape in terms of climate and tectonic activity. geomorphic coupling. These systems encompass hillslopes dominated by diffusive surface erosion and/or landsliding, steep confined channels dominated by debris flows, and purely alluvial channels flowing along major valley floors where fluvial transport prevails. In this context, the overall process of sediment transfer across landscape components and the associated disturbance-cascade are poorly understood, including the relative importance of one geomorphic process over the others at the watershed scale. In places where hillslopes and channels are well-connected, transport processes overlap, hence strongly interact via geomorphic coupling. The term coupling is used in geomorphology (e.g.,Brunsden and Thornes, 1979; Caine and Swanson, 1989) to indicate the degree of connectivity between hillslope and fluvial processes. Coupled systems exhibit direct colluvial-alluvial interaction, as opposed to decoupled (or buffered) systems, where colluvial sediment inputs do not reach the channel network. Evaluation of degree of coupling is critical to drainage basin sediment dynamics as it controls (i) sediment and process-disturbance cascades, and (ii) in what proportion hillslope denudation rate contributes to drainage basin sediment storage and fluvial sediment yield respectively (e.g., Roberts and Church, 1986; Reid and Dunne, 1996). In geomorphology, the importance of coupling between channels and adjacent hillslopes has been long acknowledged (e.g., Korup, 2005; Fryirs et al., 2007). However, relatively little work has attempted to assess its role in a systematic way. Partly because only very few empirical studies (both field-based and remotely-sensed) have tried to combine hillslopes and channelized landscape components (Benda et al., 1998). In this lecture, we will (i) evaluate how hillslope-channel connectivity can affect channel-reach morphology, channel geometry, and sediment transport potential through published examples and unpublished datasets; (ii) propose future research needs on the topic.
abstract + slide
Lanscape evolution, sediment flux, sediment sources, hillslopes, channels, buffer
English
ESF TOPO-EUROPE Workshop and PhD Summer School on Detecting Landscape Change
2010
NGF Abstracts and Proceedings of the Geological Society of Norway
978-82-92394-60-1
2010
3
none
Brardinoni, F. (2010). Hillslope-channel connectivity. In NGF Abstracts and Proceedings of the Geological Society of Norway.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/10281/38249
Citazioni
  • Scopus ND
  • ???jsp.display-item.citation.isi??? ND
Social impact