Outputs

A follow up of the workshop has been published on EOS – Transactions (Vol. 95, No. 42, 21 October 2014)

You can access the published version at this link

http://onlinelibrary.wiley.com/doi/10.1002/2014EO420007/abstract

 

Future Challenges and Opportunities for Research into Braiding Rivers

Eleven years after the last Braided Rivers Conference (Birmingham, 2003), a group of 47 scientists from 11 countries met at le Domaine de Sainte Croix, France, to discuss future directions for research into the form and dynamics of braided rivers. The meeting was organized as an “Open Space Workshop”, where people were invited to form ad-hoc working groups and review different research themes. The discussions were summarized and reported to the plenary assembly at the end of each day. More than half of the participants were PhD candidates and postdoctoral scholars, who also had the possibility to present their research in a poster session. A one-day field trip on the Drome illustrated river resilience to anthropic impacts and alternative solutions for restoration of river form and function, including the role of vegetation.

Participants reviewed the existing state of the science and highlighted emerging opportunities to advance understanding. A key theme arising from the discussion was the inadequacy of existing tools and metrics to characterize uniquely the diversity of multi-channel river systems. This was seen as a first-order weakness that has stalled the identification of a set of universal conditions for braiding, which occurs in a diversity of geomorphic and hydro-climatic settings, ranging from proglacial gravel-bed streams to large, low gradient, sand-bed rivers. There was a consensus that significant advances could be made by exploiting recent developments in earth observation technologies, in particular, airborne and terrestrial LiDAR, 3d image reconstruction, sub-surface geophysics, and multibeam echo sounding. Measurements of flow and sediment transport are more challenging, though necessary in order to tackle the problem of understanding and predicting braiding morphodynamics and sedimentary characteristics. Numerical modeling opens exciting opportunities for virtual experiments of braided rivers and can be used to guide future investigation, supported by field measurements and laboratory experiments, although future models require improved methods for reproducing lateral channel migration.

A primary challenge for our science is to develop methods to better use data obtained by new technologies and to quantify how braided rivers evolve during floods and in response to long-term environmental forcing. Such analysis should aim to characterize the morphologic, morphodynamic and sedimentological signatures of systems across the state-space range of braided rivers.

From a river management point of view, future research must focus on the parameters controlling braided river evolution, in terms of hydrological disturbance, catchment scale sediment dynamics and vegetation colonization. The participants also emphasized the need to define the ecological template of these heterogeneous environments, with an improved understanding of the interrelationship between the physical environment and ecological functioning. For rapid progress towards these challenges, the workshop highlighted the need for a multi-scale approach to the study of braiding based on collaborative research that fosters data sharing and community-led model development and testing.

The success of the workshop was only possible with the enthusiastic contribution of all the participants, the hard work of the local organizing committee and lead provided by the scientific steering group.

 

Documents produced during the workshop are accessible for participants, please contact matilde.welber@gmail.com

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