Archaeal lipids reveal climate‐driven changes in microbial ecology at Lake El'gygytgyn (Far East Russia) during the Plio‐Pleistocene. (23rd July 2021)

• Record Type: Journal Article
• Authors: Daniels, William C.; Castañeda, Isla S.; Salacup, Jeffrey M.; Habicht, M. Helen; Lindberg, Kurt R.; Brigham‐Grette, Julie
• Other Names: Melles Martin guestEditor.; Fedorov Grigory guestEditor.; Svendsen John Inge guestEditor.; Brigham‐Grette Julie guestEditor.; Wagner Bernd guestEditor.
• Is Part Of: Journal of quaternary science. Volume 37:Number 5(2022)
• Page Start: 900
• Page End: 914
• Publication Date: 2021-07-23
• Subjects: Arctic -- isoprenoid glycerol dialkyl glycerol tetraethers -- Pleistocene -- Pliocene; Geology, Stratigraphic -- Quaternary -- Periodicals; Paleontology -- Quaternary -- Periodicals; 551.79
• DOI: 10.1002/jqs.3347
• Languages: English
• ISSNs: 0267-8179

Abstract

ABSTRACT: Isoprenoid glycerol dialkyl glycerol tetraethers (iGDGTs) are commonly preserved molecular biomarkers of archaea whose distributions can be used to reconstruct past temperature, and possibly, methane and nitrogen cycling. To date, iGDGT systematics have not been widely investigated in Arctic lacustrine environments. Here, we analyze iGDGTs in sediments of Lake El'gygytgyn, located in the Russian Arctic, to reconstruct the paleoenvironmental conditions from the Pliocene to today using TEX86 and other indices. The TEX86 ‐inferred temperature history shows a long‐term warming trend, in stark contrast to other Arctic records and other proxies from Lake El'gygytgyn, suggesting that non‐temperature factors obfuscate the use of TEX86 at this site. Other GDGT‐based indices including the BIT Index, ΔRing Index, Methane Index and the GDGT‐0/crenarchaeol ratio suggest that TEX86 is strongly influenced by archaeal community changes. The most significant community shifts are observed c . 2.4 Ma and record an increase in Euryarchaeota production and/or a decrease in Thaumarchaeota production, which was driven by the establishment of permafrost and perennial lake ice during the early Pleistocene. Overall, this study demonstrates an important interpretative framework for iGDGTs in lacustrine systems and describes variations in Arctic climate and lake biogeochemistry over timescales of thousands to millions of years.