Summer rainfall dissolved organic carbon, solute, and sediment fluxes in a small Arctic coastal catchment on Herschel Island (Yukon Territory, Canada)

Arctic Science

Scott F. Lamoureux¹  Hugues Lantuit²  Caroline Coch²  Michael Fritz³  Christian Knoblauch⁴  Isabell Eischeid⁵  Jaroslav Obu⁶ 

[1] Department of Geography and Planning, Queen’s University, Mackintosh-Corry Hall, Room E208, Kingston, ON K7L 3N6, Canada.;Department of Periglacial Research, Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Telegrafenberg A45, Potsdam 14473, Germany. Institute of Earth and Environmental Science, University of Potsdam, Karl-Liebknecht-Straße 24/25, Potsdam 14476, Germany.;Department of Periglacial Research, Helmholtz Centre for Polar and Marine Research, Alfred Wegener Institute, Telegrafenberg A45, Potsdam 14473, Germany.;Institute of Soil Science, Universität Hamburg, Allende-Platz 2, Hamburg 20146, Germany.;Norwegian Polar Institute, Framsenteret, Hjalmar Johansens gate 14, Tromsø 9296, Norway.;Section of Physical Geography and Hydrology, Geologibygningen, University of Oslo, Sem Sælands vei 1, Oslo 0371, Norway.;

关键词: permafrost;    hydrology;    lateral fluxes;    hysteresis;    climate change;   

DOI  :  10.1139/as-2018-0010

来源: DOAJ

【 摘 要 】

Coastal ecosystems in the Arctic are affected by climate change. As summer rainfall frequency and intensity are projected to increase in the future, more organic matter, nutrients and sediment could be mobilized and transported into the coastal nearshore zones. However, knowledge of current processes and future changes is limited. We investigated streamflow dynamics and the impacts of summer rainfall on lateral fluxes in a small coastal catchment on Herschel Island in the western Canadian Arctic. For the summer monitoring periods of 2014–2016, mean dissolved organic matter flux over 17 days amounted to 82.7 ± 30.7 kg km−2 and mean total dissolved solids flux to 5252 ± 1224 kg km−2. Flux of suspended sediment was 7245 kg km−2 in 2015, and 369 kg km−2 in 2016. We found that 2.0% of suspended sediment was composed of particulate organic carbon. Data and hysteresis analysis suggest a limited supply of sediments; their interannual variability is most likely caused by short-lived localized disturbances. In contrast, our results imply that dissolved organic carbon is widely available throughout the catchment and exhibits positive linear relationship with runoff. We hypothesize that increased projected rainfall in the future will result in a similar increase of dissolved organic carbon fluxes.

【 授权许可】

Unknown