A catchment-scale model of mountain stream channel morphologies in southeast Australia

An evaluation of stream characteristics in glacial versus fluvial process domains in the Colorado Front Range

“…Gradients associated with specific stream morphologies in this study do not necessarily match the stream gradients predicted by Montgomery and Buffington (1997) for streams in the U.S. Pacific Northwest or the stream gradient range identified for specific stream types in other regions of the world (e.g., Thompson et al, 2006Thompson et al, , 2008Brardinoni and Hassan, 2007) (Fig. 5).…”

“…Although these models are useful for large or lowland rivers, they may not be as applicable for low-order (first-to third-order) streams in mountainous areas because of abrupt downstream changes in geomorphic history (e.g., glaciations: Arp et al, 2007;Brardinoni and Hassan, 2007; and history of landslide-producing variations in valley width: May et al, 2013), geology (e.g., Adams and Spotila, 2005;Wohl, 2005;Thompson et al, 2008), and climate (Wohl, 2010b) within mountainous terrains. These abrupt downstream changes create segmented longitudinal profiles and spatial variability in valley and channel geometry and disturbance regimes over short (10 1 -10 3 m) distances in mountain streams, which can have limited ability to readily adjust channel morphology to spatial variation in substrate resistance and sediment supply (Wohl, 2010b).…”

“…Sediment dynamics in mountainous headwaters are directly related to the diverse morphology in mountain streams. The persistence of a specific stream morphology is maintained by roughness and energy dissipation influenced by sediment dynamics and by larger clasts that are only moved during extreme events (Montgomery and Buffington, 1997;Flores et al, 2006;Thompson et al, 2008).…”

“…Much of the previous research regarding trends in channel geometry of mountain streams either (i) comes from climate and tectonic regimes that differ from the semiarid, tectonically stable Colorado Front Range, such as the U.S. Pacific Northwest region (Montgomery and Buffington, 1997;Montgomery, 1999;Buffington et al, 2004;Brardinoni and Hassan, 2007;Buffington and Tonina, 2009) or southeastern Australia (Thompson et al, 2008), (ii) was not designed to include the entire range of channel types we examine here (e.g., Merritt, 2005, 2008), or (iii) does not explicitly evaluate how correlations between channel type and potential control variables differ between process domains.…”

Predicting wetted width in any river at any discharge

“…No consideration was made for any physical processes such as considering planform adjustment by distinguishing between straight, meandering and braided channels (Dodov and Foufoula-Georgiou, 2004b). Other physical processes which might infl uence channel morphology include the infl uence of vegetation (Tal et al, 2004), fi ne sediment deposition (Haschenburger and Cowie, 2009) and stream order (Thompson et al, 2008).…”