Denitrification in the Hypolimnion of Permanently Ice-Covered Lake Bonney, Antarctica

The distribution of denitrification was investigated in the hypolimnion of the east and west lobes of permanently ice-covered Lake Bonney, Taylor Valley, Antarctica. Anomalously high concentrations of dissolved inorganic nitrogen (DIN; nitrate, nitrite, ammonium and nitrous oxide) in the oxygen-depl...

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Published in:Aquatic Microbial Ecology
Main Authors: Ward, B. B., Granger, J., Maldonado, M. T., Casciotti, K. L., Harris, S., Wells, Mark
Format: Text
Language:unknown
Published: DigitalCommons@UMaine 2005
Subjects:
Online Access:https://digitalcommons.library.umaine.edu/sms_facpub/31
https://doi.org/10.3354/ame038295
https://digitalcommons.library.umaine.edu/context/sms_facpub/article/1030/viewcontent/Wells.38.3.295.pdf
id ftmaineuniv:oai:digitalcommons.library.umaine.edu:sms_facpub-1030
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spelling ftmaineuniv:oai:digitalcommons.library.umaine.edu:sms_facpub-1030 2024-09-15T17:40:06+00:00 Denitrification in the Hypolimnion of Permanently Ice-Covered Lake Bonney, Antarctica Ward, B. B. Granger, J. Maldonado, M. T. Casciotti, K. L. Harris, S. Wells, Mark 2005-03-18T08:00:00Z application/pdf https://digitalcommons.library.umaine.edu/sms_facpub/31 https://doi.org/10.3354/ame038295 https://digitalcommons.library.umaine.edu/context/sms_facpub/article/1030/viewcontent/Wells.38.3.295.pdf unknown DigitalCommons@UMaine https://digitalcommons.library.umaine.edu/sms_facpub/31 doi:10.3354/ame038295 https://digitalcommons.library.umaine.edu/context/sms_facpub/article/1030/viewcontent/Wells.38.3.295.pdf Marine Sciences Faculty Scholarship Antarctica denitrification metal chelators trace metals bacteria Lake Bonney text 2005 ftmaineuniv https://doi.org/10.3354/ame038295 2024-07-24T05:38:40Z The distribution of denitrification was investigated in the hypolimnion of the east and west lobes of permanently ice-covered Lake Bonney, Taylor Valley, Antarctica. Anomalously high concentrations of dissolved inorganic nitrogen (DIN; nitrate, nitrite, ammonium and nitrous oxide) in the oxygen-depleted hypolimnion of the east lobe of the Lake implied that denitrification is or was active in the west, but not in the east lobe. While previous investigations reported no detectable denitrification in the east lobe, we measured active denitrification in samples from both the east and west lobes. In the west lobe, measured denitrification rates exhibited a maximum at the depth of the chemocline and denitrification was not detectable in either the oxic surface waters or in the deep water where nitrate was absent. In the east lobe, denitrification was detected below the chemocline, at the depths where ammonium, nitrate, nitrite and nitrous oxide are all present at anomalously high levels, Trace metal availability was manipulated in incubation experiments in order to determine whether trace metal toxicity in the east lobe could explain the difference in nitrogen cycling between the 2 lobes. There were no consistent stimulatory effects of metal chelators or nutrient addition on the rate of denitrification in either lobe, so that the mechanisms underlying the unusual N cycle of the east lobe remain unknown. We conclude that all the ingredients necessary to allow denitrification to occur are present in the east lobe. However, even though denitrification could be detected under certain conditions in incubations, denitrification is inhibited under the in situ conditions of the lake. Text Antarc* Antarctica The University of Maine: DigitalCommons@UMaine Aquatic Microbial Ecology 38 295 307
institution Open Polar
collection The University of Maine: DigitalCommons@UMaine
op_collection_id ftmaineuniv
language unknown
topic Antarctica
denitrification
metal chelators
trace metals
bacteria
Lake Bonney
spellingShingle Antarctica
denitrification
metal chelators
trace metals
bacteria
Lake Bonney
Ward, B. B.
Granger, J.
Maldonado, M. T.
Casciotti, K. L.
Harris, S.
Wells, Mark
Denitrification in the Hypolimnion of Permanently Ice-Covered Lake Bonney, Antarctica
topic_facet Antarctica
denitrification
metal chelators
trace metals
bacteria
Lake Bonney
description The distribution of denitrification was investigated in the hypolimnion of the east and west lobes of permanently ice-covered Lake Bonney, Taylor Valley, Antarctica. Anomalously high concentrations of dissolved inorganic nitrogen (DIN; nitrate, nitrite, ammonium and nitrous oxide) in the oxygen-depleted hypolimnion of the east lobe of the Lake implied that denitrification is or was active in the west, but not in the east lobe. While previous investigations reported no detectable denitrification in the east lobe, we measured active denitrification in samples from both the east and west lobes. In the west lobe, measured denitrification rates exhibited a maximum at the depth of the chemocline and denitrification was not detectable in either the oxic surface waters or in the deep water where nitrate was absent. In the east lobe, denitrification was detected below the chemocline, at the depths where ammonium, nitrate, nitrite and nitrous oxide are all present at anomalously high levels, Trace metal availability was manipulated in incubation experiments in order to determine whether trace metal toxicity in the east lobe could explain the difference in nitrogen cycling between the 2 lobes. There were no consistent stimulatory effects of metal chelators or nutrient addition on the rate of denitrification in either lobe, so that the mechanisms underlying the unusual N cycle of the east lobe remain unknown. We conclude that all the ingredients necessary to allow denitrification to occur are present in the east lobe. However, even though denitrification could be detected under certain conditions in incubations, denitrification is inhibited under the in situ conditions of the lake.
format Text
author Ward, B. B.
Granger, J.
Maldonado, M. T.
Casciotti, K. L.
Harris, S.
Wells, Mark
author_facet Ward, B. B.
Granger, J.
Maldonado, M. T.
Casciotti, K. L.
Harris, S.
Wells, Mark
author_sort Ward, B. B.
title Denitrification in the Hypolimnion of Permanently Ice-Covered Lake Bonney, Antarctica
title_short Denitrification in the Hypolimnion of Permanently Ice-Covered Lake Bonney, Antarctica
title_full Denitrification in the Hypolimnion of Permanently Ice-Covered Lake Bonney, Antarctica
title_fullStr Denitrification in the Hypolimnion of Permanently Ice-Covered Lake Bonney, Antarctica
title_full_unstemmed Denitrification in the Hypolimnion of Permanently Ice-Covered Lake Bonney, Antarctica
title_sort denitrification in the hypolimnion of permanently ice-covered lake bonney, antarctica
publisher DigitalCommons@UMaine
publishDate 2005
url https://digitalcommons.library.umaine.edu/sms_facpub/31
https://doi.org/10.3354/ame038295
https://digitalcommons.library.umaine.edu/context/sms_facpub/article/1030/viewcontent/Wells.38.3.295.pdf
genre Antarc*
Antarctica
genre_facet Antarc*
Antarctica
op_source Marine Sciences Faculty Scholarship
op_relation https://digitalcommons.library.umaine.edu/sms_facpub/31
doi:10.3354/ame038295
https://digitalcommons.library.umaine.edu/context/sms_facpub/article/1030/viewcontent/Wells.38.3.295.pdf
op_doi https://doi.org/10.3354/ame038295
container_title Aquatic Microbial Ecology
container_volume 38
container_start_page 295
op_container_end_page 307
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