First pan-Arctic assessment of dissolved organic carbon in lakes of the permafrost region
<jats:p>Abstract. Lakes in permafrost regions are dynamic landscape components and play an important role for climate change feedbacks. Lake processes such as mineralization and flocculation of dissolved organic carbon (DOC), one of the main carbon fractions in lakes, contribute to the greenhouse effect and are part of the global carbon cycle. These processes are in the focus of climate research, but studies so far are limited to specific study regions. In our synthesis, we analyzed 2167 water samples from 1833 lakes across the Arctic in permafrost regions of Alaska, Canada, Greenland, and Siberia to provide first pan-Arctic insights for linkages between DOC concentrations and the environment. Using published data and unpublished datasets from the author team, we report regional DOC differences linked to latitude, permafrost zones, ecoregions, geology, near-surface soil organic carbon contents, and ground ice classification of each lake region. The lake DOC concentrations in our dataset range from 0 to 1130 mg L−1 (10.8 mg L−1 median DOC concentration). Regarding the permafrost regions of our synthesis, we found median lake DOC concentrations of 12.4 mg L−1 (Siberia), 12.3 mg L−1 (Alaska), 10.3 mg L−1 (Greenland), and 4.5 mg L−1 (Canada). Our synthesis shows a significant relationship between lake DOC concentration and lake ecoregion. We found higher lake DOC concentrations at boreal permafrost sites compared to tundra sites. We found significantly higher DOC concentrations in lakes in regions with ice-rich syngenetic permafrost deposits (yedoma) compared to non-yedoma lakes and a weak but significant relationship between soil organic carbon content and lake DOC concentration as well as between ground ice content and lake DOC. Our pan-Arctic dataset shows that the DOC concentration of a lake depends on its environmental properties, especially on permafrost extent and ecoregion, as well as vegetation, which is the most important driver of lake DOC in this study. This new dataset will be fundamental to quantify a pan-Arctic lake DOC pool for estimations of the impact of lake DOC on the global carbon cycle and climate change. </jats:p>
AWI Organizations > Geosciences > Junior Research Group: COPER
AWI Organizations > Geosciences > Junior Research Group: PETA-CARB
AWI Organizations > Geosciences > Terrestrial Environmental Systems
Arctic Mainland
Arctic Mainland > Canadian Arctic
Arctic Mainland > Greenland
Arctic Mainland > Russian Arctic > Lena Delta
Arctic Mainland > Russian Arctic
Arctic Land Expeditions > RU-Land_2016_Keperveem
Arctic Land Expeditions > RU-Land_2013_Lena
Arctic Land Expeditions > RU-Land_2014_Lena
Arctic Land Expeditions > RU-Land_2015_Yamal
Arctic Land Expeditions > RU-Land_2016_Lena
Arctic Land Expeditions > RU-Land_2013_Taymyr
Arctic Land Expeditions > CA-Land_2012_YukonCoast
Arctic Land Expeditions > CA-Land_2013_YukonCoast
Arctic Land Expeditions > CA-Land_2014_YukonCoast
Arctic Land Expeditions > CA-Land_2015_YukonCoast