TY - JOUR

T1 - Archaeal community changes in Lateglacial lake sediments

T2 - Evidence from ancient DNA

AU - Ahmed, Engy

AU - Parducci, Laura

AU - Unneberg, Per

AU - Ågren, Rasmus

AU - Schenk, Frederik

AU - Rattray, Jayne E.

AU - Han, Lu

AU - Muschitiello, Francesco

AU - Pedersen, Mikkel W.

AU - Smittenberg, Rienk H.

AU - Yamoah, Kweku Afrifa

AU - Slotte, Tanja

AU - Wohlfarth, Barbara

PY - 2018

Y1 - 2018

N2 - The Lateglacial/early Holocene sediments from the ancient lake at Hässeldala Port, southern Sweden provide an important archive for the environmental and climatic shifts at the end of the last ice age and the transition into the present Interglacial. The existing multi-proxy data set highlights the complex interplay of physical and ecological changes in response to climatic shifts and lake status changes. Yet, it remains unclear how microorganisms, such as Archaea, which do not leave microscopic features in the sedimentary record, were affected by these climatic shifts. Here we present the metagenomic data set of Hässeldala Port with a special focus on the abundance and biodiversity of Archaea. This allows reconstructing for the first time the temporal succession of major Archaea groups between 13.9 and 10.8 ka BP by using ancient environmental DNA metagenomics and fossil archaeal cell membrane lipids. We then evaluate to which extent these findings reflect physical changes of the lake system, due to changes in lake-water summer temperature and seasonal lake-ice cover. We show that variations in archaeal composition and diversity were related to a variety of factors (e.g., changes in lake water temperature, duration of lake ice cover, rapid sediment infilling), which influenced bottom water conditions and the sediment-water interface. Methanogenic Archaea dominated during the Allerød and Younger Dryas pollen zones, when the ancient lake was likely stratified and anoxic for large parts of the year. The increase in archaeal diversity at the Younger Dryas/Holocene transition is explained by sediment infilling and formation of a mire/peatbog.

AB - The Lateglacial/early Holocene sediments from the ancient lake at Hässeldala Port, southern Sweden provide an important archive for the environmental and climatic shifts at the end of the last ice age and the transition into the present Interglacial. The existing multi-proxy data set highlights the complex interplay of physical and ecological changes in response to climatic shifts and lake status changes. Yet, it remains unclear how microorganisms, such as Archaea, which do not leave microscopic features in the sedimentary record, were affected by these climatic shifts. Here we present the metagenomic data set of Hässeldala Port with a special focus on the abundance and biodiversity of Archaea. This allows reconstructing for the first time the temporal succession of major Archaea groups between 13.9 and 10.8 ka BP by using ancient environmental DNA metagenomics and fossil archaeal cell membrane lipids. We then evaluate to which extent these findings reflect physical changes of the lake system, due to changes in lake-water summer temperature and seasonal lake-ice cover. We show that variations in archaeal composition and diversity were related to a variety of factors (e.g., changes in lake water temperature, duration of lake ice cover, rapid sediment infilling), which influenced bottom water conditions and the sediment-water interface. Methanogenic Archaea dominated during the Allerød and Younger Dryas pollen zones, when the ancient lake was likely stratified and anoxic for large parts of the year. The increase in archaeal diversity at the Younger Dryas/Holocene transition is explained by sediment infilling and formation of a mire/peatbog.

KW - Ancient DNA

KW - Archaea

KW - Lake sediments

KW - Last deglaciation

KW - Lipid biomarkers

KW - Metagenomics

KW - Paleoclimate

KW - Paleoenvironment

KW - Shotgun sequencing

KW - Southern Sweden

U2 - 10.1016/j.quascirev.2017.11.037

DO - 10.1016/j.quascirev.2017.11.037

M3 - Journal article

AN - SCOPUS:85037524584

VL - 181

SP - 19

EP - 29

JO - Quaternary Science Reviews

JF - Quaternary Science Reviews

SN - 0277-3791

ER -