Assessing sediment transfer in a large Arctic catchment using distributed runoff and soil erosion modelling

• Main Authors: Moreido, V., Bugaets, A., Motovilov, Y., Chalov, S., Fingert, E.
• Format: Conference Object
• Language: English
• Published: 2023
• Subjects: Arctic; Global warming; lena river; permafrost
• Online Access: https://gfzpublic.gfz-potsdam.de/pubman/item/item_5021481

With global warming expected to be more pronounced in the Arctic regions, soil erosion and associated sediment input to river systems is subsequently subject to increase here, too. This study attempts to understand complex processes involved in runoff generation, and sediment transport in the Lena River basin, and to quantify their respective fluxes at the river outlet. To assess the rate of soil erosion in the Lena River basin we augmented the regional distributed hydrological model ECOMAG with a soil erosion calculation routine MUSLE model. The ECOMAG model is used to generate runoff from a distributed network of elementary catchments, each having a unique distribution of hydrological response units accounting for various soil, vegetation and groundwater properties, as well as seasonal thawing of permafrost. For each elementary catchment the MUSLE routine was calculated on a daily timestep to assess the amount of sediment entering the stream network during snowmelt and rainfall. The model was calibrated using the available measurement data of streamflow and sediment runoff from the river gauging network. The selected approach allowed for correct simulation of the observed streamflow discharge and sediment load time-series and is applicable for the impact studies in this region. The study was conducted under RSF project 21-17-00181.