Abstract
Mountainous regions are highly sensitive to climatic changes. The warming trend of the last decades and the related retreat of glaciers and permafrost consequently imply strong changes regarding sediment transport patterns due to intensive melting and the (re-)activation of potential sediment sources. The present study aims to present a holistic approach to analyze sediment cascades in this climatic and geomorphological context.
The study area, the partly glaciated Solda / Sulden catchment in the area of Val Venosta / Vinschgau (Italian Alps), was mapped geomorphologically to define the spatial distribution of source, transport and deposition areas. Subsequently, potential sediment pathways between topographically connected geomorphological landforms form the base to analyse the network of transport processes within the catchment in detail. The identification of spatial and temporal hot-spots as well as triggering factors of these sediment transport processes will be obtained by combining the results of the network analysis with results of DEMs of Difference (DoDs) representing different time intervals (months/years). Furthermore, measurements of fluvial sediment transport play an important role to qualitatively validate the findings. The monitoring combines regularly conducted direct measurements of both bedload and suspended sediments and continuous indirect measurements (e.g. geophones, turbidimeters). Sampling points are located at glacier outlets, in the proglacial river and at the outlet of the catchment.
Finally, based on the overall result of the study, the significance of extreme meteorological events, like heavy rain storms or heat waves, for the intensity and spatial distribution of sediment transport will be estimated to outline potential risks for infrastructure or population.