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Greenhouse gas production and lipid biomarker distribution in Yedoma and Alas thermokarst lake sediments in Eastern Siberia.

https://arctichealth.org/en/permalink/ahliterature311240
Source
Glob Chang Biol. 2021 Mar 28; :
Publication Type
Journal Article
Date
Mar-28-2021
Author
Loeka L Jongejans
Susanne Liebner
Christian Knoblauch
Kai Mangelsdorf
Mathias Ulrich
Guido Grosse
George Tanski
Alexander N Fedorov
Pavel Ya Konstantinov
Torben Windirsch
Julia Wiedmann
Jens Strauss
Author Affiliation
Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, Permafrost Research Section, Potsdam, Germany.
Source
Glob Chang Biol. 2021 Mar 28; :
Date
Mar-28-2021
Language
English
Publication Type
Journal Article
Abstract
Permafrost thaw leads to thermokarst lake formation and talik growth tens of meters deep, enabling microbial decomposition of formerly frozen organic matter (OM). We analyzed two 17-m-long thermokarst lake sediment cores taken in Central Yakutia, Russia. One core was from an Alas lake in a Holocene thermokarst basin that underwent multiple lake generations, and the second core from a young Yedoma upland lake (formed ~70 years ago) whose sediments have thawed for the first time since deposition. This comparison provides a glance into OM fate in thawing Yedoma deposits. We analyzed total organic carbon (TOC) and dissolved organic carbon (DOC) content, n-alkane concentrations, and bacterial and archaeal membrane markers. Furthermore, we conducted 1-year-long incubations (4°C, dark) and measured anaerobic carbon dioxide (CO2 ) and methane (CH4 ) production. The sediments from both cores contained little TOC (0.7 ± 0.4 wt%), but DOC values were relatively high, with the highest values in the frozen Yedoma lake sediments (1620 mg L-1 ). Cumulative greenhouse gas (GHG) production after 1 year was highest in the Yedoma lake sediments (226 ± 212 µg CO2 -C g-1  dw, 28 ± 36 µg CH4 -C g-1  dw) and 3 and 1.5 times lower in the Alas lake sediments, respectively (75 ± 76 µg CO2 -C g-1  dw, 19 ± 29 µg CH4 -C g-1  dw). The highest CO2 production in the frozen Yedoma lake sediments likely results from decomposition of readily bioavailable OM, while highest CH4 production in the non-frozen top sediments of this core suggests that methanogenic communities established upon thaw. The lower GHG production in the non-frozen Alas lake sediments resulted from advanced OM decomposition during Holocene talik development. Furthermore, we found that drivers of CO2 and CH4 production differ following thaw. Our results suggest that GHG production from TOC-poor mineral deposits, which are widespread throughout the Arctic, can be substantial. Therefore, our novel data are relevant for vast ice-rich permafrost deposits vulnerable to thermokarst formation.
PubMed ID
33774862 View in PubMed
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The history of seabird colonies and the North Water ecosystem: Contributions from palaeoecological and archaeological evidence.

https://arctichealth.org/en/permalink/ahliterature290182
Source
Ambio. 2018 Apr; 47(Suppl 2):175-192
Publication Type
Journal Article
Date
Apr-2018
Author
Thomas A Davidson
Sebastian Wetterich
Kasper L Johansen
Bjarne Grønnow
Torben Windirsch
Erik Jeppesen
Jari Syväranta
Jesper Olsen
Ivan González-Bergonzoni
Astrid Strunk
Nicolaj K Larsen
Hanno Meyer
Jens Søndergaard
Rune Dietz
Igor Eulears
Anders Mosbech
Author Affiliation
Department of Bioscience, Arctic Research Centre, Aarhus University, Vejlsøvej 25, 8600, Silkeborg, Denmark. thd@bios.au.dk.
Source
Ambio. 2018 Apr; 47(Suppl 2):175-192
Date
Apr-2018
Language
English
Publication Type
Journal Article
Abstract
The North Water (NOW) polynya is one of the most productive marine areas of the Arctic and an important breeding area for millions of seabirds. There is, however, little information on the dynamics of the polynya or the bird populations over the long term. Here, we used sediment archives from a lake and peat deposits along the Greenland coast of the NOW polynya to track long-term patterns in the dynamics of the seabird populations. Radiocarbon dates show that the thick-billed murre (Uria lomvia) and the common eider (Somateria mollissima) have been present for at least 5500 cal. years. The first recorded arrival of the little auk (Alle alle) was around 4400 cal. years BP at Annikitsoq, with arrival at Qeqertaq (Salve Ø) colony dated to 3600 cal. years BP. Concentrations of cadmium and phosphorus (both abundant in little auk guano) in the lake and peat cores suggest that there was a period of large variation in bird numbers between 2500 and 1500 cal. years BP. The little auk arrival times show a strong accord with past periods of colder climate and with some aspects of human settlement in the area.
Notes
Cites: Proc Biol Sci. 2009 Feb 7;276(1656):591-6 PMID 18945662
Cites: Proc Biol Sci. 2017 Feb 22;284(1849): PMID 28202811
Cites: Nature. 2002 Apr 18;416(6882):729-33 PMID 11961553
Cites: Ambio. 2018 Apr;47(Suppl 2):296-309 PMID 29520749
Cites: Ambio. 2018 Apr;47(Suppl 2):226-243 PMID 29516440
Cites: Nature. 2009 Sep 17;461(7262):385-8 PMID 19759618
Cites: Proc Natl Acad Sci U S A. 2017 Jun 6;114(23 ):5952-5957 PMID 28512225
PubMed ID
29516438 View in PubMed
Less detail

The history of seabird colonies and the North Water ecosystem: Contributions from palaeoecological and archaeological evidence.

https://arctichealth.org/en/permalink/ahliterature295705
Source
Ambio. 2018 Apr; 47(Suppl 2):175-192
Publication Type
Journal Article
Date
Apr-2018
Author
Thomas A Davidson
Sebastian Wetterich
Kasper L Johansen
Bjarne Grønnow
Torben Windirsch
Erik Jeppesen
Jari Syväranta
Jesper Olsen
Ivan González-Bergonzoni
Astrid Strunk
Nicolaj K Larsen
Hanno Meyer
Jens Søndergaard
Rune Dietz
Igor Eulears
Anders Mosbech
Author Affiliation
Department of Bioscience, Arctic Research Centre, Aarhus University, Vejlsøvej 25, 8600, Silkeborg, Denmark. thd@bios.au.dk.
Source
Ambio. 2018 Apr; 47(Suppl 2):175-192
Date
Apr-2018
Language
English
Publication Type
Journal Article
Keywords
Animals
Arctic Regions
Charadriiformes
Ecosystem
Greenland
Population Dynamics
Water
Abstract
The North Water (NOW) polynya is one of the most productive marine areas of the Arctic and an important breeding area for millions of seabirds. There is, however, little information on the dynamics of the polynya or the bird populations over the long term. Here, we used sediment archives from a lake and peat deposits along the Greenland coast of the NOW polynya to track long-term patterns in the dynamics of the seabird populations. Radiocarbon dates show that the thick-billed murre (Uria lomvia) and the common eider (Somateria mollissima) have been present for at least 5500 cal. years. The first recorded arrival of the little auk (Alle alle) was around 4400 cal. years BP at Annikitsoq, with arrival at Qeqertaq (Salve Ø) colony dated to 3600 cal. years BP. Concentrations of cadmium and phosphorus (both abundant in little auk guano) in the lake and peat cores suggest that there was a period of large variation in bird numbers between 2500 and 1500 cal. years BP. The little auk arrival times show a strong accord with past periods of colder climate and with some aspects of human settlement in the area.
Notes
Cites: Proc Biol Sci. 2009 Feb 7;276(1656):591-6 PMID 18945662
Cites: Proc Biol Sci. 2017 Feb 22;284(1849): PMID 28202811
Cites: Nature. 2002 Apr 18;416(6882):729-33 PMID 11961553
Cites: Ambio. 2018 Apr;47(Suppl 2):296-309 PMID 29520749
Cites: Ambio. 2018 Apr;47(Suppl 2):226-243 PMID 29516440
Cites: Nature. 2009 Sep 17;461(7262):385-8 PMID 19759618
Cites: Proc Natl Acad Sci U S A. 2017 Jun 6;114(23 ):5952-5957 PMID 28512225
PubMed ID
29516438 View in PubMed
Less detail