Recent trends in the chemistry of major northern rivers signal widespread Arctic change

• Published in: Nature Geoscience
• Main Authors: Tank, Suzanne, Mcclelland, James, Spencer, Robert, Shiklomanov, Alexander, Suslova, Anya, Moatar, Florentina, Amon, Rainer, Cooper, Lee, Elias, Greg, Gordeev, Vyacheslav, Guay, Christopher, Gurtovaya, Tatiana Yu., Kosmenko, Lyudmila, Mutter, Edda, Peterson, Bruce, Peucker-Ehrenbrink, Bernhard, Raymond, Peter, Schuster, Paul, Scott, Lindsay, Staples, Robin, Striegl, Robert, Tretiakov, Mikhail, Zhulidov, Alexander, Zimov, Nikita, Zimov, Sergey, Holmes, Robert
• Other Authors: University of Alberta, Marine Biological Laboratory (MBL), University of Chicago, Florida State University Tallahassee (FSU), University of New Hampshire (UNH), Woodwell Climate Research Center, RiverLy - Fonctionnement des hydrosystèmes (RiverLy), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Texas A&M University Galveston, University of Maryland Center for Environmental Science (UMCES), University of Maryland System, Western Arctic Research Center, Inuvik, Northwest Territories, P.P. Shirshov Institute of Oceanology (SIO), Russian Academy of Sciences Moscow (RAS), Mamala Research LLC, Honolulu, HI, South Russia Centre for Preparation and Implementation of International Projec, Rostov-on-Don, Ministry of Natural Resources and Environment of the Russian Federation, Rostov-on-Don, Yukon River Inter-Tribal Watershed Council, Anchorage, AK, Woods Hole Oceanographic Institution (WHOI), Yale University New Haven, US Geological Survey Boulder, United States Geological Survey Reston (USGS), Government of the Northwest Territories Yellowknife, Canada, Arctic and Antarctic Research Institute (AARI), Russian Federal Service for Hydrometeorology and Environmental Monitoring (Roshydromet), Pacific Geographical Institute of the Far Eastern Branch of the Russian Academy of Sciences, Chersky
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2023
• Subjects: [SDE]Environmental Sciences; Arctic Basin; permafrost
• Online Access: https://hal.inrae.fr/hal-04198078; https://hal.inrae.fr/hal-04198078/document; https://hal.inrae.fr/hal-04198078/file/latest.pdf; https://doi.org/10.1038/s41561-023-01247-7

International audience Rivers integrate processes occurring throughout their watersheds and aretherefore sentinels of change across broad spatial scales. River chemistryalso regulates ecosystem function across Earth’s land–ocean continuum,exerting control from the micro- (for example, local food web) to the macro-(for example, global carbon cycle) scale. In the rapidly warming Arctic, awide range of processes—from permafrost thaw to biological uptake andtransformation—might reasonably alter river water chemistry. Here weuse data from major rivers that collectively drain two-thirds of the ArcticOcean watershed to assess widespread change in biogeochemical functionwithin the pan-Arctic basin from 2003 to 2019. While the oceanward flux ofalkalinity and associated ions increased markedly over this time frame, nitrateand other inorganic nutrient fluxes declined. Fluxes of dissolved organiccarbon showed no overall trend. This divergence in response indicatesthe perturbation of multiple processes on land, with implications forbiogeochemical cycling in the coastal ocean. We anticipate that these findingswill facilitate refinement of conceptual and numerical models of currentand future functioning of Arctic coastal ecosystems and spur research onscale-dependent change across the river-integrated Arctic domain.