Prof. Bruce Rhoads

University of Illinois, USA
http://www.geog.illinois.edu/people/rhoads/index.html

Linking Flow Structure and Channel Form in Natural and Managed River Systems
A key focus of contemporary research in fluvial geomorphology is to seek process-based understandings of river dynamics. Such understandings are viewed as important to the development of compel-ling theoretical explanations of how rivers evolve over time and space and to successful efforts to manage rivers effectively. The dynamics of alluvial rivers, or those formed in erodible material, fundamentally involve interactions between flowing water and the morphology of river channels as mediated through the movement of sediment. Thus, interactions between flow structure and channel form lie at the heart of processbased understandings of river dynamics. In many cases, these interactions are complex because the mean flow, turbulence and channel form can all vary threedimensionally.

This talk reviews two research programs on river dynamics that emphasize the importance of understanding the linkages between flow structure and channel form:

  1. efforts to naturalize human-modified channels in urban and rural environments and
  2. process-based investigations of confluences, meander bends and cutoffs in small and large rivers.

The first program integrates flume experiments, numerical modeling and field studies to formulate design criteria based on geomorphological principles for establishing stable, selfsustaining poolriffle sequences in artificially straightened channels. The second program is mainly a field effort to explore how flow structure and channel form interact in confluences, cutoffs and meander bends and to examine how these interactions might vary with scale. The field effort is currently being supplemented by numerical modeling of flow through confluences and the work on meander bends complements experimental work on the dynamics of complex, elongated meander bends that has been conducted at the the Hydrosystems Laboratory, University of Illinois. Together these two research programs are helping to advance our understanding of processbased linkages between flow and form in rivers, thereby contributing both to fluvial theory to effective river management.

Ort
05.08.2010 15:00 Uhr

Großer Hörsaal
Müggelseedamm 310
12587 Berlin-Friedrichshagen 








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