14,000-year carbon accumulation dynamics in a Siberian lake reveal catchment and lake productivity changes

• Published in: Frontiers in Earth Science
• Main Authors: Hughes-Allen, Lara, Bouchard, Frédéric, Hatté, Christine, Meyer, Hanno, Pestryakova, Lyudmila A., Diekmann, Bernhard, Subetto, Dmitry A., Biskaborn, Boris K.
• Other Authors: Géosciences Paris Saclay (GEOPS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung = Alfred Wegener Institute for Polar and Marine Research = Institut Alfred-Wegener pour la recherche polaire et marine (AWI), Helmholtz-Gemeinschaft = Helmholtz Association, Université Laval Québec (ULaval), Laboratoire des Sciences du Climat et de l'Environnement Gif-sur-Yvette (LSCE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Géochrononologie Traceurs Archéométrie (GEOTRAC), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)), Université de Yakutsk, Herzen State Pedagogical University of Russia, Siberian Branch of the Russian Academy of Sciences (SB RAS), DS was supported by Ministry of Education of the Russian Federation (project No. FSZN-2020-16). LH-A and FB are supported by the Agence nationale de la recherche (ANR) through the Make Our Planet Great Again initiative (Programme d’investissements d’avenir – project no. ANR-17-MPGA-0014)., ANR-17-MPGA-0014,PEGS,PErmafrost and Greenhouse gas dynamics in Siberia(2017)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2021
• Subjects: paleolimnology; lake sediment core; late Pleistocene; Holocene; Eastern Siberia; organic carbon accumulation; stable carbon isotope (13C); [SDU.OCEAN]Sciences of the Universe [physics]/Ocean; Atmosphere; [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces; environment; Yakutia; Siberia
• Online Access: https://hal.science/hal-03453509; https://hal.science/hal-03453509/document; https://hal.science/hal-03453509/file/Hughes-Allen_2021_FrontiersEarthSc%283%29.pdf; https://doi.org/10.3389/feart.2021.710257

International audience A multi-proxy paleolimnological analysis of a sediment core sequence from Lake MalayaChabyda in Central Yakutia (Eastern Siberia, Russia) was conducted to investigatechanges in lake processes, including lake development, sediment and organic carbonaccumulation, and changes in primary productivity, within the context of Late Pleistoceneand Holocene climate change. Age-depth modeling with 14C indicates that the maximumage of the sediment core is ∼14 cal kBP. Three distinct sedimentary units were identifiedwithin the sediment core. Sedimentological and biogeochemical properties in the deepestsection of the core (663–584 cm; 14.1–12.3 cal kBP) suggests a lake environment mostlyinfluenced by terrestrial vegetation, where organic carbon accumulation might have beenrelatively low (average ∼100 g OC m−2 a−1), although much higher than the global modernaverage. The middle section of the core (584–376 cm; 12.3–9.0 cal kBP) is characterizedby higher primary productivity in the lake, much higher sedimentation, and a remarkableincrease in OC delivery (average ∼300 g OC m−2 a−1). Conditions in the upper section ofthe core (<376 cm; < 9.0 cal kBP) suggest high primary productivity in the lake and highOC accumulation rates (average ∼200 g OC m−2 a−1), with stable environmentalconditions. The transition from organic-poor and mostly terrestrial vegetation inputs(TOC/TNatomic ratios ∼20) to conditions dominated by aquatic primary productivity(TOC/TNatomic ratios <15) occurs at around 12.3 cal kBP. This resulted in an increasein the sedimentation rate of OC within the lake, illustrated by higher sedimentation ratesand very high total OC concentrations (>30%) measured in the upper section of the core.Compact lake morphology and high sedimentation rates likely resulted in this lake acting asa significant OC sink since the Pleistocene-Holocene transition. Sediment accumulationrates declined after ∼8 cal k BP, however total OC concentrations were still notably high.TOC/TNatomic and isotopic data ...