Photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great Arctic delta
Lake-rich Arctic river deltas are recharged with terrigenous dissolved organic matter (DOM) during the yearly peak water period corresponding with the solstice (24 h day−1 solar irradiance). Bacteria-free DOM collected during peak Mackenzie River discharge was exposed to sunlight for up to 14 days i...
Published in: | Arctic Science |
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Language: | English French |
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Canadian Science Publishing
2018
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Online Access: | https://doi.org/10.1139/as-2017-0055 https://doaj.org/article/6ac37c10a9de4c799b7ed7c2738f7734 |
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fttriple:oai:gotriple.eu:oai:doaj.org/article:6ac37c10a9de4c799b7ed7c2738f7734 2023-05-15T14:22:21+02:00 Photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great Arctic delta Jolie A.L. Gareis Lance F.W. Lesack 2018-09-01 https://doi.org/10.1139/as-2017-0055 https://doaj.org/article/6ac37c10a9de4c799b7ed7c2738f7734 en fr eng fre Canadian Science Publishing doi:10.1139/as-2017-0055 2368-7460 https://doaj.org/article/6ac37c10a9de4c799b7ed7c2738f7734 undefined Arctic Science, Vol 4, Iss 4, Pp 557-583 (2018) circumpolar river delta photodegradation dissolved organic matter bacterial metabolism mackenzie river envir anthro-se Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2018 fttriple https://doi.org/10.1139/as-2017-0055 2023-01-22T19:27:29Z Lake-rich Arctic river deltas are recharged with terrigenous dissolved organic matter (DOM) during the yearly peak water period corresponding with the solstice (24 h day−1 solar irradiance). Bacteria-free DOM collected during peak Mackenzie River discharge was exposed to sunlight for up to 14 days in June 2010. As solar exposure increased, carbon and lignin concentrations declined (10% and 42%, respectively, after 14 days), as did DOM absorptivity (62% after 14 days), aromaticity, and molecular weight. Photochemical changes were on par with those normally observed in Mackenzie Delta lakes over the entire open-water season. When irradiated freshet DOM was provided as a substrate, no significant differences were observed in community-level metabolism among five bacterial communities from representative delta habitats. However, bacterial abundance was significantly greater when nonirradiated (0 day) rather than irradiated DOM (7 or 14 days) was provided, while cell-specific metabolic measures revealed that per-cell bacterial production and growth efficiency were significantly greater when communities were provided irradiated substrate. This complex response to rapid DOM photodegradation may result from the production of inhibitory reactive oxygen species (ROS), along with shifts in bacterial community composition to species that are better able to tolerate ROS, or metabolize the labile photodegraded DOM. Article in Journal/Newspaper Arctic Arctic Mackenzie Delta Mackenzie river Unknown Arctic Mackenzie Delta ENVELOPE(-136.672,-136.672,68.833,68.833) Mackenzie River Arctic Science 4 4 557 583 |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
English French |
topic |
circumpolar river delta photodegradation dissolved organic matter bacterial metabolism mackenzie river envir anthro-se |
spellingShingle |
circumpolar river delta photodegradation dissolved organic matter bacterial metabolism mackenzie river envir anthro-se Jolie A.L. Gareis Lance F.W. Lesack Photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great Arctic delta |
topic_facet |
circumpolar river delta photodegradation dissolved organic matter bacterial metabolism mackenzie river envir anthro-se |
description |
Lake-rich Arctic river deltas are recharged with terrigenous dissolved organic matter (DOM) during the yearly peak water period corresponding with the solstice (24 h day−1 solar irradiance). Bacteria-free DOM collected during peak Mackenzie River discharge was exposed to sunlight for up to 14 days in June 2010. As solar exposure increased, carbon and lignin concentrations declined (10% and 42%, respectively, after 14 days), as did DOM absorptivity (62% after 14 days), aromaticity, and molecular weight. Photochemical changes were on par with those normally observed in Mackenzie Delta lakes over the entire open-water season. When irradiated freshet DOM was provided as a substrate, no significant differences were observed in community-level metabolism among five bacterial communities from representative delta habitats. However, bacterial abundance was significantly greater when nonirradiated (0 day) rather than irradiated DOM (7 or 14 days) was provided, while cell-specific metabolic measures revealed that per-cell bacterial production and growth efficiency were significantly greater when communities were provided irradiated substrate. This complex response to rapid DOM photodegradation may result from the production of inhibitory reactive oxygen species (ROS), along with shifts in bacterial community composition to species that are better able to tolerate ROS, or metabolize the labile photodegraded DOM. |
format |
Article in Journal/Newspaper |
author |
Jolie A.L. Gareis Lance F.W. Lesack |
author_facet |
Jolie A.L. Gareis Lance F.W. Lesack |
author_sort |
Jolie A.L. Gareis |
title |
Photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great Arctic delta |
title_short |
Photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great Arctic delta |
title_full |
Photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great Arctic delta |
title_fullStr |
Photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great Arctic delta |
title_full_unstemmed |
Photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great Arctic delta |
title_sort |
photodegraded dissolved organic matter from peak freshet river discharge as a substrate for bacterial production in a lake-rich great arctic delta |
publisher |
Canadian Science Publishing |
publishDate |
2018 |
url |
https://doi.org/10.1139/as-2017-0055 https://doaj.org/article/6ac37c10a9de4c799b7ed7c2738f7734 |
long_lat |
ENVELOPE(-136.672,-136.672,68.833,68.833) |
geographic |
Arctic Mackenzie Delta Mackenzie River |
geographic_facet |
Arctic Mackenzie Delta Mackenzie River |
genre |
Arctic Arctic Mackenzie Delta Mackenzie river |
genre_facet |
Arctic Arctic Mackenzie Delta Mackenzie river |
op_source |
Arctic Science, Vol 4, Iss 4, Pp 557-583 (2018) |
op_relation |
doi:10.1139/as-2017-0055 2368-7460 https://doaj.org/article/6ac37c10a9de4c799b7ed7c2738f7734 |
op_rights |
undefined |
op_doi |
https://doi.org/10.1139/as-2017-0055 |
container_title |
Arctic Science |
container_volume |
4 |
container_issue |
4 |
container_start_page |
557 |
op_container_end_page |
583 |
_version_ |
1766294969740427264 |