Channel morphodynamics on a small proglacial braid plain (Fagge River, Gepatschferner, Austria)

D Morche,K Dubberke,A Schuchardt,H Baewert

doi:10.5194/piahs-367-109-2015

Abstract

Abstract. Braid plains are important sediment stores in high mountains, particularly in the glacier forefields of Alpine glaciers. Proglacial braid plains receive sediment input from glacial meltwater and proglacial sediment sources like moraines and glacio-fluvial deposits. The channel morphodynamics on the braid plains are strongly related to the sediment transport and flow regime of the proglacial river. This study deals with channel morphodynamics on a small proglacial braid plain in the European Alps. It focuses on two different time scales. Decadal channel planform changes were assessed by remote sensing approaches. The recent channel bed changes were investigated by cross-sectional surveys and particle counts in 2013. This study is part of the DFG/FWF funded interdisciplinary research project PROSA (High-resolution measurements of morphodynamics in rapidly changing PROglacial Systems of the Alps).

Highlights

Braid plains are important landforms in summit regions of the world in glacier forefields of Alpine glaciers (Geilhausen et al 2012a, Geilhausen et al 2012b)
The channel morphodynamics on proglacial braid plains are strongly related to the sediment transport and flow regime of the river draining the upstream glacier (Warburton 1992, 1994, Stott 2002, Luchi et al 2007,)
Decadal channel planform changes Channel planforms were mapped for each year with available orthophotos

Summary

Introduction

Braid plains are important landforms in summit regions of the world in glacier forefields of Alpine glaciers (Geilhausen et al 2012a, Geilhausen et al 2012b). Braid plains develop in alluvial channel reaches or upstream of barriers and are key parameters in the sediment budget (Maizels 1979, Warburton 1990). They can switch their role from sediment sinks, when more sediment is deposited than eroded, to sediment sources, when erosion dominates (Bimböse et al 2011). The channel morphodynamics on proglacial braid plains are strongly related to the sediment transport and flow regime of the river draining the upstream glacier (Warburton 1992, 1994, Stott 2002, Luchi et al 2007,). Marren & Toomath (2014) highlighted that topographic forcing in deglaciating areas is associated with channel pattern change

Methods

Results

Conclusion