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Arctic mid-winter phytoplankton growth revealed by autonomous profilers.

ABSTRACT: It is widely believed that during winter and spring, Arctic marine phytoplankton cannot grow until sea ice and snow cover start melting and transmit sufficient irradiance, but there is little observational evidence for that paradigm. To explore the life of phytoplankton during and after the polar night, we used robotic ice-avoiding profiling floats to measure ocean optics and phytoplankton characteristics continuously through two annual cycles in Baffin Bay, an Arctic sea that is covered by ice for 7 months a year. We demonstrate that net phytoplankton growth occurred even under 100% ice cover as early as February and that it resulted at least partly from photosynthesis. This highlights the adaptation of Arctic phytoplankton to extreme low-light conditions, which may be key to their survival before seeding the spring bloom.

SUBMITTER: Randelhoff A

PROVIDER: S-EPMC7518875 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Arctic mid-winter phytoplankton growth revealed by autonomous profilers.

Randelhoff Achim A Lacour Léo L Marec Claudie C Leymarie Edouard E Lagunas José J Xing Xiaogang X Darnis Gérald G Penkerc'h Christophe C Sampei Makoto M Fortier Louis L D'Ortenzio Fabrizio F Claustre Hervé H Babin Marcel M

Science advances 20200925 39

It is widely believed that during winter and spring, Arctic marine phytoplankton cannot grow until sea ice and snow cover start melting and transmit sufficient irradiance, but there is little observational evidence for that paradigm. To explore the life of phytoplankton during and after the polar night, we used robotic ice-avoiding profiling floats to measure ocean optics and phytoplankton characteristics continuously through two annual cycles in Baffin Bay, an Arctic sea that is covered by ice ...[more]

PMID: 32978152

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