Chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western Arctic
The Arctic is warming at a rate nearly twice the global average, leading to thawing permafrost, increased coastal erosion, and enhanced delivery of riverine terrestrially-derived dissolved organic matter (tDOM) to coastal waters. This humic-rich tDOM has the ability to attenuate light required for p...
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ftwilliammarycol:oai:scholarworks.wm.edu:vimsarticles-1762 2023-06-11T04:08:49+02:00 Chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western Arctic Sipler, RE Baer, SE Connelly, TL Frischer, ME Roberts, QN Yager, PL Bronk, DA 2017-01-01T08:00:00Z application/pdf https://scholarworks.wm.edu/vimsarticles/762 doi: 10.1002/lno.10541 https://scholarworks.wm.edu/context/vimsarticles/article/1762/viewcontent/lno.10541.pdf unknown W&M ScholarWorks https://scholarworks.wm.edu/vimsarticles/762 doi: 10.1002/lno.10541 https://scholarworks.wm.edu/context/vimsarticles/article/1762/viewcontent/lno.10541.pdf VIMS Articles Primary Productivity Climate-Change Community Structure Ancient Permafrost Optical-Properties Humic Substances Time-Series Carbon Ocean River Physical Sciences Peer-Reviewed Articles Aquaculture and Fisheries text 2017 ftwilliammarycol https://doi.org/10.1002/lno.10541 2023-05-04T17:43:31Z The Arctic is warming at a rate nearly twice the global average, leading to thawing permafrost, increased coastal erosion, and enhanced delivery of riverine terrestrially-derived dissolved organic matter (tDOM) to coastal waters. This humic-rich tDOM has the ability to attenuate light required for photosynthesis and stimulate heterotrophic growth by supplying a source of labile organic carbon. Due to tDOM's high carbon to nitrogen (C : N) ratio, additional nitrogen is required for microorganisms to utilize this excess carbon for growth, thus exacerbating competition between autotrophs and heterotrophs for limiting nutrients and potentially reducing primary production. The effect of Arctic tDOM additions on nitrate uptake by two microplankton size fractions in the coastal Chukchi Sea was quantified using 15 N tracer methods. To assess the biogeochemical vs. spectral impacts of tDOM, the uptake incubations were amended with either tDOM or light attenuating films that mimic light absorption by the tDOM. Nitrate uptake and primary production rates in the larger, predominantly phytoplankton, size fraction generally decreased with increasing tDOM additions. The change in light attenuation alone accounted for a similar to 50% reduction in nitrate uptake. Responses in the smaller size fraction varied seasonally with tDOM additions stimulating uptake in spring and suppressing it in summer. The largest variation in summer nitrate uptake can be explained by the shared effect of biogeochemistry and light attenuation. Therefore, large increases in tDOM delivery currently occurring and predicted to increase in the coastal Arctic, could reduce primary production, broadly impact nitrogen and carbon cycling, and affect higher trophic levels. Text Arctic Chukchi Chukchi Sea Climate change permafrost Phytoplankton W&M ScholarWorks Arctic Chukchi Sea Limnology and Oceanography 62 5 1881 1894 |
institution |
Open Polar |
collection |
W&M ScholarWorks |
op_collection_id |
ftwilliammarycol |
language |
unknown |
topic |
Primary Productivity Climate-Change Community Structure Ancient Permafrost Optical-Properties Humic Substances Time-Series Carbon Ocean River Physical Sciences Peer-Reviewed Articles Aquaculture and Fisheries |
spellingShingle |
Primary Productivity Climate-Change Community Structure Ancient Permafrost Optical-Properties Humic Substances Time-Series Carbon Ocean River Physical Sciences Peer-Reviewed Articles Aquaculture and Fisheries Sipler, RE Baer, SE Connelly, TL Frischer, ME Roberts, QN Yager, PL Bronk, DA Chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western Arctic |
topic_facet |
Primary Productivity Climate-Change Community Structure Ancient Permafrost Optical-Properties Humic Substances Time-Series Carbon Ocean River Physical Sciences Peer-Reviewed Articles Aquaculture and Fisheries |
description |
The Arctic is warming at a rate nearly twice the global average, leading to thawing permafrost, increased coastal erosion, and enhanced delivery of riverine terrestrially-derived dissolved organic matter (tDOM) to coastal waters. This humic-rich tDOM has the ability to attenuate light required for photosynthesis and stimulate heterotrophic growth by supplying a source of labile organic carbon. Due to tDOM's high carbon to nitrogen (C : N) ratio, additional nitrogen is required for microorganisms to utilize this excess carbon for growth, thus exacerbating competition between autotrophs and heterotrophs for limiting nutrients and potentially reducing primary production. The effect of Arctic tDOM additions on nitrate uptake by two microplankton size fractions in the coastal Chukchi Sea was quantified using 15 N tracer methods. To assess the biogeochemical vs. spectral impacts of tDOM, the uptake incubations were amended with either tDOM or light attenuating films that mimic light absorption by the tDOM. Nitrate uptake and primary production rates in the larger, predominantly phytoplankton, size fraction generally decreased with increasing tDOM additions. The change in light attenuation alone accounted for a similar to 50% reduction in nitrate uptake. Responses in the smaller size fraction varied seasonally with tDOM additions stimulating uptake in spring and suppressing it in summer. The largest variation in summer nitrate uptake can be explained by the shared effect of biogeochemistry and light attenuation. Therefore, large increases in tDOM delivery currently occurring and predicted to increase in the coastal Arctic, could reduce primary production, broadly impact nitrogen and carbon cycling, and affect higher trophic levels. |
format |
Text |
author |
Sipler, RE Baer, SE Connelly, TL Frischer, ME Roberts, QN Yager, PL Bronk, DA |
author_facet |
Sipler, RE Baer, SE Connelly, TL Frischer, ME Roberts, QN Yager, PL Bronk, DA |
author_sort |
Sipler, RE |
title |
Chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western Arctic |
title_short |
Chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western Arctic |
title_full |
Chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western Arctic |
title_fullStr |
Chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western Arctic |
title_full_unstemmed |
Chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western Arctic |
title_sort |
chemical and photophysiological impact of terrestrially-derived dissolved organic matter on nitrate uptake in the coastal western arctic |
publisher |
W&M ScholarWorks |
publishDate |
2017 |
url |
https://scholarworks.wm.edu/vimsarticles/762 https://scholarworks.wm.edu/context/vimsarticles/article/1762/viewcontent/lno.10541.pdf |
geographic |
Arctic Chukchi Sea |
geographic_facet |
Arctic Chukchi Sea |
genre |
Arctic Chukchi Chukchi Sea Climate change permafrost Phytoplankton |
genre_facet |
Arctic Chukchi Chukchi Sea Climate change permafrost Phytoplankton |
op_source |
VIMS Articles |
op_relation |
https://scholarworks.wm.edu/vimsarticles/762 doi: 10.1002/lno.10541 https://scholarworks.wm.edu/context/vimsarticles/article/1762/viewcontent/lno.10541.pdf |
op_doi |
https://doi.org/10.1002/lno.10541 |
container_title |
Limnology and Oceanography |
container_volume |
62 |
container_issue |
5 |
container_start_page |
1881 |
op_container_end_page |
1894 |
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1768382336650444800 |