Glacier stream activity in the proglacial area of debris covered glacier in Aosta Valley, Italy: an application of dendroglaciology

Abstract

Dendrochronology has often been used to study past and present glacier dynamics and fluctuations. Miage Glacier is the most important Italian debris covered glacier with a tree coverage growing on its debris layer. In this study we present the possibility to obtain information using tree vegetation growing in the proglacial area of Miage Glacier, highlighting the continuous remobilization of the debris by the glacial stream flow. Dating scars, compression wood and rings width releases and reductions we detected the presence of areas directly affected by glacial discharge and others characterized by boulders falling from the glacier front. The concentration of growth anomalies starting from 1984 probably indicates a more intense glacial activity influencing the forest vegetation. The data from this preliminary work suggest the possibility to extract information about the glacier behaviour not only using trees growing on the glacial tongue but also the tree vegetation colonizing the proglacial environment.