Observations of late-winter marine microbial activity in an ice-covered fjord, west Greenland

Direct observations of marine microbial metabolism are sparse in the Arctic, particularly under sea ice during winter. This paper presents the first observations of Arctic winter microbial activity under sea ice in a west Greenland fjord (Lillefjord, ∼ 70 ∘ N). Here, measured changes in dissolved ox...

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Bibliographic Details
Published in:Earth System Science Data
Main Authors: D. Chandler, S. Mackie
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2020
Subjects:
Online Access:https://doi.org/10.5194/essd-12-897-2020
https://doaj.org/article/e106eeeffda74a559bb394f943416f96
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Summary:Direct observations of marine microbial metabolism are sparse in the Arctic, particularly under sea ice during winter. This paper presents the first observations of Arctic winter microbial activity under sea ice in a west Greenland fjord (Lillefjord, ∼ 70 ∘ N). Here, measured changes in dissolved oxygen (DO) content in light and dark in situ incubations were used to calculate net community productivity, respiration and photosynthesis rates. Data were collected at two fully ice covered sites during February 2013, shortly after the end of the polar night. Averaged over the full study period, dark incubations showed statistically significant decreases in DO of <math xmlns="http://www.w3.org/1998/Math/MathML" id="M3" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>-</mo><mn mathvariant="normal">0.36</mn><mo>±</mo><mn mathvariant="normal">0.24</mn></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="64pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="5fff6923f9e55cfcaf93eb4211138c29"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="essd-12-897-2020-ie00001.svg" width="64pt" height="10pt" src="essd-12-897-2020-ie00001.png"/></svg:svg> (near shore) and <math xmlns="http://www.w3.org/1998/Math/MathML" id="M4" display="inline" overflow="scroll" dspmath="mathml"><mrow><mo>-</mo><mn mathvariant="normal">0.09</mn><mo>±</mo><mn mathvariant="normal">0.07</mn></mrow></math> <svg:svg xmlns:svg="http://www.w3.org/2000/svg" width="64pt" height="10pt" class="svg-formula" dspmath="mathimg" md5hash="fe73e5e154e0ac55a702a96f7c8f6364"><svg:image xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="essd-12-897-2020-ie00002.svg" width="64pt" height="10pt" src="essd-12-897-2020-ie00002.png"/></svg:svg> g O 2 m −3 d −1 (fjord centre), indicating respiration rates that were 2–20 times greater than ...