Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters
Photophysiological processes as well as uptake characteristics of iron and inorganic carbon were studied in inshore phytoplankton assemblages of the Western Antarctic Peninsula (WAP) and offshore assemblages of the Drake Passage. Chlorophyll a concentrations and primary productivity decreased from i...
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ftunivgeneve:oai:unige.ch:aou:unige:83757 2023-10-01T03:51:16+02:00 Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters Trimborn, Scarlett Hoppe, Clara J.M. Taylor, Bettina B. Bracher, Astrid Hassler, Christel 2015 https://archive-ouverte.unige.ch/unige:83757 eng eng info:eu-repo/semantics/altIdentifier/doi/10.1016/j.dsr.2014.12.010 https://archive-ouverte.unige.ch/unige:83757 unige:83757 info:eu-repo/semantics/openAccess ISSN: 0967-0637 Deep-sea research. Part 1. Oceanographic research papers, vol. 98 (2015) p. 115-124 info:eu-repo/classification/ddc/550 Photophysiology Primary production Southern Ocean Inorganic carbon uptake Iron uptake Humic-like substances info:eu-repo/semantics/article Text Article scientifique info:eu-repo/semantics/publishedVersion 2015 ftunivgeneve https://doi.org/10.1016/j.dsr.2014.12.010 2023-09-07T07:31:18Z Photophysiological processes as well as uptake characteristics of iron and inorganic carbon were studied in inshore phytoplankton assemblages of the Western Antarctic Peninsula (WAP) and offshore assemblages of the Drake Passage. Chlorophyll a concentrations and primary productivity decreased from in- to offshore waters. The inverse relationship between low maximum quantum yields of photochemistry in PSII (Fv/Fm) and large sizes of functional absorption cross sections (σPSII) in offshore communities indicated iron-limitation. Congruently, the negative correlation between Fv/Fm values and iron uptake rates across our sampling locations suggest an overall better iron uptake capacity in iron-limited pelagic phytoplankton communities. Highest iron uptake capacities could be related to relative abundances of the haptophyte Phaeocystis antarctica. As chlorophyll a-specific concentrations of humic-like substances were similarly high in offshore and inshore stations, we suggest humic-like substances may play an important role in iron chemistry in both coastal and pelagic phytoplankton assemblages. Regarding inorganic carbon uptake kinetics, the measured maximum short-term uptake rates (Vmax(CO2)) and apparent half-saturation constants (K1/2(CO2)) did not differ between offshore and inshore phytoplankton. Moreover, Vmax(CO2) and K1/2(CO2) did not exhibit any CO2-dependent trend over the natural pCO2 range from 237 to 507 µatm. K1/2(CO2) strongly varied among the sampled phytoplankton communities, ranging between 3.5 and 35.3 µmol L−1 CO2. While in many of the sampled phytoplankton communities, the operation of carbon-concentrating mechanisms (CCMs) was indicated by low K1/2(CO2) values relative to ambient CO2 concentrations, some coastal sites exhibited higher values, suggesting down-regulated CCMs. Overall, our results demonstrate a complex interplay between photophysiological processes, iron and carbon uptake of phytoplankton communities of the WAP and the Drake Passage. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica Drake Passage Southern Ocean Université de Genève: Archive ouverte UNIGE Antarctic Southern Ocean Antarctic Peninsula Drake Passage Deep Sea Research Part I: Oceanographic Research Papers 98 115 124 |
institution |
Open Polar |
collection |
Université de Genève: Archive ouverte UNIGE |
op_collection_id |
ftunivgeneve |
language |
English |
topic |
info:eu-repo/classification/ddc/550 Photophysiology Primary production Southern Ocean Inorganic carbon uptake Iron uptake Humic-like substances |
spellingShingle |
info:eu-repo/classification/ddc/550 Photophysiology Primary production Southern Ocean Inorganic carbon uptake Iron uptake Humic-like substances Trimborn, Scarlett Hoppe, Clara J.M. Taylor, Bettina B. Bracher, Astrid Hassler, Christel Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters |
topic_facet |
info:eu-repo/classification/ddc/550 Photophysiology Primary production Southern Ocean Inorganic carbon uptake Iron uptake Humic-like substances |
description |
Photophysiological processes as well as uptake characteristics of iron and inorganic carbon were studied in inshore phytoplankton assemblages of the Western Antarctic Peninsula (WAP) and offshore assemblages of the Drake Passage. Chlorophyll a concentrations and primary productivity decreased from in- to offshore waters. The inverse relationship between low maximum quantum yields of photochemistry in PSII (Fv/Fm) and large sizes of functional absorption cross sections (σPSII) in offshore communities indicated iron-limitation. Congruently, the negative correlation between Fv/Fm values and iron uptake rates across our sampling locations suggest an overall better iron uptake capacity in iron-limited pelagic phytoplankton communities. Highest iron uptake capacities could be related to relative abundances of the haptophyte Phaeocystis antarctica. As chlorophyll a-specific concentrations of humic-like substances were similarly high in offshore and inshore stations, we suggest humic-like substances may play an important role in iron chemistry in both coastal and pelagic phytoplankton assemblages. Regarding inorganic carbon uptake kinetics, the measured maximum short-term uptake rates (Vmax(CO2)) and apparent half-saturation constants (K1/2(CO2)) did not differ between offshore and inshore phytoplankton. Moreover, Vmax(CO2) and K1/2(CO2) did not exhibit any CO2-dependent trend over the natural pCO2 range from 237 to 507 µatm. K1/2(CO2) strongly varied among the sampled phytoplankton communities, ranging between 3.5 and 35.3 µmol L−1 CO2. While in many of the sampled phytoplankton communities, the operation of carbon-concentrating mechanisms (CCMs) was indicated by low K1/2(CO2) values relative to ambient CO2 concentrations, some coastal sites exhibited higher values, suggesting down-regulated CCMs. Overall, our results demonstrate a complex interplay between photophysiological processes, iron and carbon uptake of phytoplankton communities of the WAP and the Drake Passage. |
format |
Article in Journal/Newspaper |
author |
Trimborn, Scarlett Hoppe, Clara J.M. Taylor, Bettina B. Bracher, Astrid Hassler, Christel |
author_facet |
Trimborn, Scarlett Hoppe, Clara J.M. Taylor, Bettina B. Bracher, Astrid Hassler, Christel |
author_sort |
Trimborn, Scarlett |
title |
Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters |
title_short |
Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters |
title_full |
Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters |
title_fullStr |
Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters |
title_full_unstemmed |
Physiological characteristics of open ocean and coastal phytoplankton communities of Western Antarctic Peninsula and Drake Passage waters |
title_sort |
physiological characteristics of open ocean and coastal phytoplankton communities of western antarctic peninsula and drake passage waters |
publishDate |
2015 |
url |
https://archive-ouverte.unige.ch/unige:83757 |
geographic |
Antarctic Southern Ocean Antarctic Peninsula Drake Passage |
geographic_facet |
Antarctic Southern Ocean Antarctic Peninsula Drake Passage |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Drake Passage Southern Ocean |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Drake Passage Southern Ocean |
op_source |
ISSN: 0967-0637 Deep-sea research. Part 1. Oceanographic research papers, vol. 98 (2015) p. 115-124 |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.dsr.2014.12.010 https://archive-ouverte.unige.ch/unige:83757 unige:83757 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1016/j.dsr.2014.12.010 |
container_title |
Deep Sea Research Part I: Oceanographic Research Papers |
container_volume |
98 |
container_start_page |
115 |
op_container_end_page |
124 |
_version_ |
1778534003262881792 |