Elucidating suspended sediment dynamics in a glacierized catchment after an exceptional erosion event: The Djankuat catchment, Caucasus Mountains, Russia

A - Papers appearing in refereed journals

Tsyplenkov, A., Vanmaercke, M., Collins, A. L., Kharchenko, S. and Golosov, V. 2021. Elucidating suspended sediment dynamics in a glacierized catchment after an exceptional erosion event: The Djankuat catchment, Caucasus Mountains, Russia. Catena. 203 (105285). https://doi.org/10.1016/j.catena.2021.105285

AuthorsTsyplenkov, A., Vanmaercke, M., Collins, A. L., Kharchenko, S. and Golosov, V.
Abstract

Suspended sediment yields from glacierized catchments are often among the highest in the world, and their sediment dynamics can be highly variable. This study was undertaken in the 9.1 km2 glacierized catchment of the Djankuat River located in the Russian part of the Northern Caucasus. The outlet of the study catchment is a hydrological gauging station located at an altitude of 2635 m a.m.s.l. (‘N43◦12′31.71′′, E42◦44′05.93′′). The catchment includes a temperate valley glacier (area = 2.42 km2) and three smaller hanging glaciers, several moraine deposits, rock walls, and a large and expanding proglacial area. The main goal of our study was to assess the impact of an exceptional erosion event on 1st July 2015 (with an annual exceedance probability of less than 0.1%) on suspended sediment yields and the relative contributions of various sediment sources The work combined direct suspended sediment discharge measurements at the gauging station during five ablation seasons (2015–2019) with geomorphic mapping techniques based on detailed field observations and sediment source fingerprinting. Results show that mean annual suspended sediment yields reached 1118 t km− 2 year− 1 which is one of the highest measured estimates for any of the glacierized mountain rivers globally. About half of the annual suspended sediment flux was exported during a limited number (1–12% of the annual events) of extreme hydrological events. The sediments mobilized by bank and riverbed erosion within the new lower reach of a tributary channel which appeared after the breakthrough of a lateral moraine became the primary sediment source. It contributed over 50% of the suspended sediment on days with extreme rainfall. Contributions to the suspended sediment load from the glacier source were event-dependent and were only dominant (c. 60–70%) in the upper reaches of the proglacial area (first 800 m). The proglacial part of the study catchment with buried ice was the main sediment source (79%) during non-rain days.

KeywordsSediment yield ; Suspended sediment ; Hydrological monitoring; Source fingerprinting ; Geomorphological mapping ; Climate change
Year of Publication2021
JournalCatena
Journal citation203 (105285)
Digital Object Identifier (DOI)https://doi.org/10.1016/j.catena.2021.105285
Web address (URL)https://doi.org/10.1016/j.catena.2021.105285
Open accessPublished as non-open access
FunderBiotechnology and Biological Sciences Research Council
Funder project or codeS2N - Soil to Nutrition - Work package 3 (WP3) - Sustainable intensification - optimisation at multiple scales
The Russian Scientific Foundation 19-17-00181
Publisher's version
Output statusPublished
Publication dates
OnlineAug 2021
Publication process dates
Accepted27 Feb 2021
PublisherElsevier Science Bv
ISSN0341-8162

Permalink - https://repository.rothamsted.ac.uk/item/98427/elucidating-suspended-sediment-dynamics-in-a-glacierized-catchment-after-an-exceptional-erosion-event-the-djankuat-catchment-caucasus-mountains-russia

15 total views
35 total downloads
0 views this month
0 downloads this month
Download files as zip