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| Titel |
Soil erosion and organic carbon export by wet snow avalanches |
| VerfasserIn |
C. Rixen, O. Korup |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250067088
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| Zusammenfassung |
| A growing number of studies have begun to use sediment budgets to indirectly estimate the
cycling of biogeochemical constituents in mountainous terrain. In this context little is known
about mobilization, transport, and export rates during the snow pack season, when
large portions of alpine landscapes appear inactive compared to the more rigorous
geomorphic activity between spring and autumn. Here we expand the scarce knowledge
base on debris transport by snow avalanches and report first-order estimates of
related sediment and organic carbon export, based on field samples of some 30
wet snow-avalanche deposits in the eastern Swiss Alps. These deposits formed
snow bridges across second- to third-order mountain river channels, and contained
detritus in their surficial layers. Repeated point samples of these detrital layers
indicate a median thickness of 2-4 cm, which translates into 0.02 to 0.04 m3 of
sediment per m2 avalanche deposit surface. Grab samples encompassing a total of
>350 kg of debris indicate concentrations from 1 to 43 kg m-2 of deposit area.
Sieving and loss-on-ignition analyses show that, on average, particulate organic
carbon (POC) constitutes (37 +/- 34)% of particle sizes |
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