Academic Journals Database
Disseminating quality controlled scientific knowledge

Estimation of soil redistribution rates due to snow cover related processes in a mountainous area (Valle d'Aosta, NW Italy)

Author(s): E. Ceaglio | K. Meusburger | M. Freppaz | E. Zanini | C. Alewell

Journal: Hydrology and Earth System Sciences Discussions
ISSN 1812-2108

Volume: 8;
Issue: 5;
Start page: 8533;
Date: 2011;
VIEW PDF   PDF DOWNLOAD PDF   Download PDF Original page

Mountain areas are widely affected by soil erosion, which is commonly linked to runoff processes. Also winter processes, like snow gliding and full-depth avalanches, may be important factors that can enhance soil erosion, however the role and importance of snow movements as agents of soil redistribution are not well understood yet. The aim of this study is to provide information on the relative importance of snow related soil erosion processes in comparison to runoff processes. In the study area, which is an avalanche path characterized by intense snow movements and soil erosion, soil redistribution rates were quantified with two methods: (i) by field measurements of sediment yield in an avalanche deposition area during 2009 and 2010 winter seasons; (ii) by Caesium-137 method, which supplies the cumulative net soil loss/gain since 1986, including winter and summer soil erosion processes. The soil erosion rates estimated from the sediment yield at the avalanche deposit area (3.2 and 20.8 Mg ha−1 event−1) is comparable to the yearly erosion rates (averaged since 1986) estimated with the Cs-137 method (8.8–13.4 Mg ha−1 yr−1). The soil accumulation rate estimated with data from the avalanche deposition area (28.2 and 160.7 Mg ha−1 event−1) is even more intense than the yearly deposition rates estimated with Cs-137 (8.9–12.6 Mg ha−1 yr−1). This might be due to the high relevance of the two investigated avalanche events and/or to the discrepancy between the long-term (since 1986) signal of the Cs-137 method compared to rates of 2009 and 2010. Even though the comparability is limited by the different time scale of the applied methods, both methods yielded similar magnitudes of soil redistribution rates indicating that soil erosion due to snow movements is the main driving force of soil redistribution in the area. Therefore winter processes have to be taken into account when assessing soil erosion as they significantly contribute to soil redistribution in mountainous areas.
Why do you need a reservation system?      Save time & money - Smart Internet Solutions