Bulk characteristics, lipid quantification and compound-specific carbon isotope ratios of Mackenzie Delta lake sediments ...

• Main Authors: Lattaud, Julie, Bröder, Lisa, Haghipour, Negar, Rickli, Jörg Dominik, Giosan, Liviu, Eglinton, Timothy Ian
• Format: Article in Journal/Newspaper
• Language: English
• Published: PANGAEA 2020
• Subjects: bulk radiocarbon; Carbon isotopes; n-alkanes; Neodymium isotopes; Arctic; Canada; Mackenzie Delta
• Online Access: https://dx.doi.org/10.1594/pangaea.924201; https://doi.pangaea.de/10.1594/PANGAEA.924201

The Arctic is undergoing accelerated changes in response to ongoing modifications to the climate system, and there is a need for local to regional scale records of past climate variability in order to put these changes into context. The Mackenzie delta region in northern Canada is populated by numerous small shallow lakes. They are classified as no-, low- and high-closure (NC, LC, HC, respectively) lakes, reflecting varying degrees of connection to the river main stem, and have different sedimentation characteristics. This study examines sedimentological (mineral surface area, grain size), carbon isotopic (bulk and molecular-level) and inorganic isotopic (neodymium) characteristics of sediment cores from three lakes representing each class. We find that HC lake sediments exhibit strikingly different properties from the other lake sediments. Specifically, they are characterized by higher organic carbon loadings per unit mineral surface area and with relatively minor influence from allochthonous, petrogenic ...