The transformation and fate of sub-Arctic microphytobenthos carbon revealed through 13C-labeling

Joanne M. Oakes, Søren Rysgaard, Ronnie N. Glud, Bradley D. Eyre

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

Resumé

Microphytobenthos (MPB) at higher latitudes has been poorly studied. This study used pulse-chase C-13-labeling to investigate the production, processing, and fate of MPB-derived carbon (MPB-C) in sub-Arctic intertidal sediments over 31 d. Gross primary production (2.1 mmolCm(-2)h(-1)+/- 0.4 mmolCm(-2)h(-1)) was comparable to that reported for temperate regions. Some of the C-13 fixed by sub-Arctic MPB was rapidly (within 0.5 d) transferred to deeper sediments (below 2 cm), but most was retained within surface sediments (>70.2% of the C-13 present at any time during the study). At any time, MPB accounted for49.8% of this C-13. The C-13 content of sediment organic carbon declined over time, but>31% of the C-13 fixed within the first tidal cycle remained after 31 d, suggesting that sub-Arctic MPB may contribute to coastal carbon retention during the productive season. Over 21 d, 10.6% of the fixed C-13 was removed via DIC fluxes and 0.3% via DOC fluxes from inundated sediment, and 0.6% as CO2 from exposed sediment. The greatest loss of C-13 (38.2%) was via unmeasured pathways, including resuspension and/or removal by mobile consumers. The rates of MPB-C production and the relative importance of the pathways for MPB-C loss were similar to that observed for comparable lower latitude sediments, demonstrating that MPB at higher latitudes are not necessarily distinct from MPB at lower latitudes and probably play a similarly important role in ecosystem functioning. Apparently, local environmental conditions are more important than climate differences for determining the processing and fate of MPB-C.
OriginalsprogEngelsk
TidsskriftLimnology and Oceanography
Vol/bind61
Udgave nummer6
Sider (fra-til)2296-2308
ISSN0024-3590
DOI
StatusUdgivet - nov. 2016

Emneord

  • benthic microalgae
  • organic-matter
  • in-situ
  • nitrogen incorporation
  • intertidal sediments
  • microbial community
  • coastal sediments
  • sandy sediments
  • tracing carbon
  • salt-marsh

Citer dette

Oakes, Joanne M. ; Rysgaard, Søren ; Glud, Ronnie N. ; Eyre, Bradley D. / The transformation and fate of sub-Arctic microphytobenthos carbon revealed through 13C-labeling. I: Limnology and Oceanography. 2016 ; Bind 61, Nr. 6. s. 2296-2308.
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title = "The transformation and fate of sub-Arctic microphytobenthos carbon revealed through 13C-labeling",
abstract = "Microphytobenthos (MPB) at higher latitudes has been poorly studied. This study used pulse-chase C-13-labeling to investigate the production, processing, and fate of MPB-derived carbon (MPB-C) in sub-Arctic intertidal sediments over 31 d. Gross primary production (2.1 mmolCm(-2)h(-1)+/- 0.4 mmolCm(-2)h(-1)) was comparable to that reported for temperate regions. Some of the C-13 fixed by sub-Arctic MPB was rapidly (within 0.5 d) transferred to deeper sediments (below 2 cm), but most was retained within surface sediments (>70.2{\%} of the C-13 present at any time during the study). At any time, MPB accounted for49.8{\%} of this C-13. The C-13 content of sediment organic carbon declined over time, but>31{\%} of the C-13 fixed within the first tidal cycle remained after 31 d, suggesting that sub-Arctic MPB may contribute to coastal carbon retention during the productive season. Over 21 d, 10.6{\%} of the fixed C-13 was removed via DIC fluxes and 0.3{\%} via DOC fluxes from inundated sediment, and 0.6{\%} as CO2 from exposed sediment. The greatest loss of C-13 (38.2{\%}) was via unmeasured pathways, including resuspension and/or removal by mobile consumers. The rates of MPB-C production and the relative importance of the pathways for MPB-C loss were similar to that observed for comparable lower latitude sediments, demonstrating that MPB at higher latitudes are not necessarily distinct from MPB at lower latitudes and probably play a similarly important role in ecosystem functioning. Apparently, local environmental conditions are more important than climate differences for determining the processing and fate of MPB-C.",
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author = "Oakes, {Joanne M.} and S{\o}ren Rysgaard and Glud, {Ronnie N.} and Eyre, {Bradley D.}",
year = "2016",
month = "11",
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The transformation and fate of sub-Arctic microphytobenthos carbon revealed through 13C-labeling. / Oakes, Joanne M.; Rysgaard, Søren; Glud, Ronnie N.; Eyre, Bradley D.

I: Limnology and Oceanography, Bind 61, Nr. 6, 11.2016, s. 2296-2308.

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

TY - JOUR

T1 - The transformation and fate of sub-Arctic microphytobenthos carbon revealed through 13C-labeling

AU - Oakes, Joanne M.

AU - Rysgaard, Søren

AU - Glud, Ronnie N.

AU - Eyre, Bradley D.

PY - 2016/11

Y1 - 2016/11

N2 - Microphytobenthos (MPB) at higher latitudes has been poorly studied. This study used pulse-chase C-13-labeling to investigate the production, processing, and fate of MPB-derived carbon (MPB-C) in sub-Arctic intertidal sediments over 31 d. Gross primary production (2.1 mmolCm(-2)h(-1)+/- 0.4 mmolCm(-2)h(-1)) was comparable to that reported for temperate regions. Some of the C-13 fixed by sub-Arctic MPB was rapidly (within 0.5 d) transferred to deeper sediments (below 2 cm), but most was retained within surface sediments (>70.2% of the C-13 present at any time during the study). At any time, MPB accounted for49.8% of this C-13. The C-13 content of sediment organic carbon declined over time, but>31% of the C-13 fixed within the first tidal cycle remained after 31 d, suggesting that sub-Arctic MPB may contribute to coastal carbon retention during the productive season. Over 21 d, 10.6% of the fixed C-13 was removed via DIC fluxes and 0.3% via DOC fluxes from inundated sediment, and 0.6% as CO2 from exposed sediment. The greatest loss of C-13 (38.2%) was via unmeasured pathways, including resuspension and/or removal by mobile consumers. The rates of MPB-C production and the relative importance of the pathways for MPB-C loss were similar to that observed for comparable lower latitude sediments, demonstrating that MPB at higher latitudes are not necessarily distinct from MPB at lower latitudes and probably play a similarly important role in ecosystem functioning. Apparently, local environmental conditions are more important than climate differences for determining the processing and fate of MPB-C.

AB - Microphytobenthos (MPB) at higher latitudes has been poorly studied. This study used pulse-chase C-13-labeling to investigate the production, processing, and fate of MPB-derived carbon (MPB-C) in sub-Arctic intertidal sediments over 31 d. Gross primary production (2.1 mmolCm(-2)h(-1)+/- 0.4 mmolCm(-2)h(-1)) was comparable to that reported for temperate regions. Some of the C-13 fixed by sub-Arctic MPB was rapidly (within 0.5 d) transferred to deeper sediments (below 2 cm), but most was retained within surface sediments (>70.2% of the C-13 present at any time during the study). At any time, MPB accounted for49.8% of this C-13. The C-13 content of sediment organic carbon declined over time, but>31% of the C-13 fixed within the first tidal cycle remained after 31 d, suggesting that sub-Arctic MPB may contribute to coastal carbon retention during the productive season. Over 21 d, 10.6% of the fixed C-13 was removed via DIC fluxes and 0.3% via DOC fluxes from inundated sediment, and 0.6% as CO2 from exposed sediment. The greatest loss of C-13 (38.2%) was via unmeasured pathways, including resuspension and/or removal by mobile consumers. The rates of MPB-C production and the relative importance of the pathways for MPB-C loss were similar to that observed for comparable lower latitude sediments, demonstrating that MPB at higher latitudes are not necessarily distinct from MPB at lower latitudes and probably play a similarly important role in ecosystem functioning. Apparently, local environmental conditions are more important than climate differences for determining the processing and fate of MPB-C.

KW - benthic microalgae

KW - organic-matter

KW - in-situ

KW - nitrogen incorporation

KW - intertidal sediments

KW - microbial community

KW - coastal sediments

KW - sandy sediments

KW - tracing carbon

KW - salt-marsh

U2 - 10.1002/lno.10377

DO - 10.1002/lno.10377

M3 - Journal article

VL - 61

SP - 2296

EP - 2308

JO - Limnology and Oceanography

JF - Limnology and Oceanography

SN - 0024-3590

IS - 6

ER -