The race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler

The grazing of phytoplankton by Arctic copepods channels energy from primary producers to higher trophic levels. However, the predator-prey interactions between phytoplankton and zooplankton in the water column are difficult to study since zooplankton sampling still relies heavily on nets that rough...

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Bibliographic Details
Main Author: Schmid, Moritz
Other Authors: Fortier, Louis, Babin, Marcel
Format: Thesis
Language:French
Published: Université Laval 2017
Subjects:
geo
Online Access:https://hdl.handle.net/20.500.11794/27779
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spelling fttriple:oai:gotriple.eu:http://hdl.handle.net/20.500.11794/27779 2023-05-15T14:56:36+02:00 The race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler Schmid, Moritz Fortier, Louis Babin, Marcel Arctique, Océan 2017-01-01 https://hdl.handle.net/20.500.11794/27779 fr fre Université Laval http://hdl.handle.net/20.500.11794/27779 other CorpusUL envir geo Thesis https://vocabularies.coar-repositories.org/resource_types/c_46ec/ 2017 fttriple https://doi.org/20.500.11794/27779 2023-01-22T16:40:24Z The grazing of phytoplankton by Arctic copepods channels energy from primary producers to higher trophic levels. However, the predator-prey interactions between phytoplankton and zooplankton in the water column are difficult to study since zooplankton sampling still relies heavily on nets that roughly stratify the water column. The quantification of physiological parameters of copepods, such as lipid content, is also made at coarse vertical resolution. To overcome this limitation, this research used the Lightframe On-sight Keyspecies Investigation (LOKI) system, an underwater camera that provides 1 m vertical resolution. An automatic zooplankton identification model, based on artificial intelligence, was developed for the analysis of profiles sampled in fall 2013 in the North Water Polynya (NOW) and Nares Strait (NS), in the Canadian Arctic. The model turns LOKI images into taxonomic information and can differentiate 114 taxa (organisms and particles), including the developmental stages of copepods. Two studies were carried out based on automatically identified LOKI images. First, during a Lagrangian drift, fine-scale vertical distributions (1-m resolution) of the copepods Calanus hyperboreus, C. glacialis and Metridia longa were studied in relation to their total lipids (TL, mg) and lipid fullness (LF, %). C. hyperboreus and C. glacialis with low LF performed diel vertical migration to surface waters at night to feed, while same-stage individuals with high LF ceased migrating and remained at depth to diapause. Migration to diapause in C. hyperboreus occurred at a LF of approximately 50%, while C. glacialis needed a higher LF (60%). A bioenergetics model showed that Calanus females had enough lipids stored to diapause for over 365 days, highlighting their capacity for capital breeding. In a second study, the fine-scale vertical coupling of C. hyperboreus and C. glacialis developmental stages with their phytoplankton food was studied in the NOW and NS. Three types of copepod vertical distributions in response to ... Thesis Arctic Arctique* Calanus hyperboreus Nares strait Phytoplankton Zooplankton Copepods Unknown Arctic Nares ENVELOPE(158.167,158.167,-81.450,-81.450)
institution Open Polar
collection Unknown
op_collection_id fttriple
language French
topic envir
geo
spellingShingle envir
geo
Schmid, Moritz
The race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler
topic_facet envir
geo
description The grazing of phytoplankton by Arctic copepods channels energy from primary producers to higher trophic levels. However, the predator-prey interactions between phytoplankton and zooplankton in the water column are difficult to study since zooplankton sampling still relies heavily on nets that roughly stratify the water column. The quantification of physiological parameters of copepods, such as lipid content, is also made at coarse vertical resolution. To overcome this limitation, this research used the Lightframe On-sight Keyspecies Investigation (LOKI) system, an underwater camera that provides 1 m vertical resolution. An automatic zooplankton identification model, based on artificial intelligence, was developed for the analysis of profiles sampled in fall 2013 in the North Water Polynya (NOW) and Nares Strait (NS), in the Canadian Arctic. The model turns LOKI images into taxonomic information and can differentiate 114 taxa (organisms and particles), including the developmental stages of copepods. Two studies were carried out based on automatically identified LOKI images. First, during a Lagrangian drift, fine-scale vertical distributions (1-m resolution) of the copepods Calanus hyperboreus, C. glacialis and Metridia longa were studied in relation to their total lipids (TL, mg) and lipid fullness (LF, %). C. hyperboreus and C. glacialis with low LF performed diel vertical migration to surface waters at night to feed, while same-stage individuals with high LF ceased migrating and remained at depth to diapause. Migration to diapause in C. hyperboreus occurred at a LF of approximately 50%, while C. glacialis needed a higher LF (60%). A bioenergetics model showed that Calanus females had enough lipids stored to diapause for over 365 days, highlighting their capacity for capital breeding. In a second study, the fine-scale vertical coupling of C. hyperboreus and C. glacialis developmental stages with their phytoplankton food was studied in the NOW and NS. Three types of copepod vertical distributions in response to ...
author2 Fortier, Louis
Babin, Marcel
format Thesis
author Schmid, Moritz
author_facet Schmid, Moritz
author_sort Schmid, Moritz
title The race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler
title_short The race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler
title_full The race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler
title_fullStr The race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler
title_full_unstemmed The race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler
title_sort race for lipids : ontogeny of the fine-scale vertical co-distribution of arctic calanoid copepods and their phytoplankton food as elucidated by artificial intelligence coupled with an imaging profiler
publisher Université Laval
publishDate 2017
url https://hdl.handle.net/20.500.11794/27779
op_coverage Arctique, Océan
long_lat ENVELOPE(158.167,158.167,-81.450,-81.450)
geographic Arctic
Nares
geographic_facet Arctic
Nares
genre Arctic
Arctique*
Calanus hyperboreus
Nares strait
Phytoplankton
Zooplankton
Copepods
genre_facet Arctic
Arctique*
Calanus hyperboreus
Nares strait
Phytoplankton
Zooplankton
Copepods
op_source CorpusUL
op_relation http://hdl.handle.net/20.500.11794/27779
op_rights other
op_doi https://doi.org/20.500.11794/27779
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