6. CONCLUSIONS
Applying a number of “standard” hydrogeological tools in a high alpine
catchment allows the differentiation of multiple recharge sources for
and subsequently delayed discharge from a shallow groundwater aquifer,
i.e. an active rock glacier. Faster flow through the system is
accomplished by suprapermafrost, whereas slower flow by subpermafrost;
although intermediate flow paths are to be expected and indicate the
complex internal structure of these landforms. Groundwater contribution
does play an important role in rock glacier spring discharge, especially
during the winter months or periods of little recharge. Ice melt
contribution from cirque glaciers within the catchment of the rock
glacier spring mask the potential – but likely still negligible -
influence of permafrost ice melt during snow-free periods. A future
scenario with vanished cirque glaciers, diminishing amounts of
permafrost ice within the rock glacier and thereby increasing storage
capacity of the shallow groundwater store within the rock glacier might
suggest an increasing importance of these (ice-) debris accumulations in
shaping the runoff pattern of alpine catchments.
The storage-discharge characteristics of the investigated active rock
glacier catchment is an example of a shallow groundwater aquifer in
alpine catchments that ought to be considered when analysing (future)
river runoff characteristics in alpine catchments as these provide
retarded runoff during periods with little to no recharge. The provided
steady baseflow and delayed release of water within such an alpine
catchment is crucial to understand and critical to sustain ecological
diversity in the light of climate change.