Monsoonal hillslope processes determine grain size-specific suspended sediment fluxes in a trans-Himalayan river
- Sediments in rivers record the dynamics of erosion processes. While bulk sediment fluxes are easily and routinely obtained, sediment caliber remains underexplored when inferring erosion mechanisms. Yet sediment grain size distributions may be the key to discriminating their origin. We have studied grain size-specific suspended sediment fluxes in the Kali Gandaki, a major trans-Himalayan river. Two strategically located gauging stations enable tracing of sediment caliber on either side of the Himalayan orographic barrier. The data show that fine sediment input into the northern headwaters is persistent, while coarse sediment comes from the High Himalayas during the summer monsoon. A temporally matching landslide inventory similarly indicates the prominence of monsoon-driven hillslope mass wasting. Thus, mechanisms of sediment supply can leave strong traces in the fluvial caliber, which could project well beyond the mountain front and add to the variability of the sedimentary record of orogen erosion.
Author details: | Martin Struck, Christoff AndermannORCiDGND, Niels HoviusORCiDGND, Oliver KorupORCiDGND, Jens M. TurowskiORCiD, Raj Bista, Hari P. Pandit, Ranjan K. Dahal |
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DOI: | https://doi.org/10.1002/2015GL063360 |
ISSN: | 0094-8276 |
ISSN: | 1944-8007 |
Title of parent work (English): | Geophysical research letters |
Publisher: | American Geophysical Union |
Place of publishing: | Washington |
Publication type: | Article |
Language: | English |
Year of first publication: | 2015 |
Publication year: | 2015 |
Release date: | 2017/03/27 |
Tag: | Himalayas; erosion; grain size; landslide; river transport; suspended sediments |
Volume: | 42 |
Issue: | 7 |
Number of pages: | 7 |
First page: | 2302 |
Last Page: | 2308 |
Funding institution: | Potsdam Research Cluster for Georisk Analysis, Environmental Change and Sustainability (PROGRESS); German Academic Exchange Service; German Helmholtz Association [PD-039] |
Organizational units: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Geowissenschaften |
Peer review: | Referiert |
Institution name at the time of the publication: | Mathematisch-Naturwissenschaftliche Fakultät / Institut für Erd- und Umweltwissenschaften |