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Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes

Temperature and nutrients are key factors affecting the growth, cell size, and physiology of marine phytoplankton. In the ocean, temperature and nutrient availability often co-vary because temperature drives vertical stratification, which further controls nutrient upwelling. This makes it difficult...

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Autores principales: Skau, Lars Fredrik, Andersen, Tom, Thrane, Jan-Erik, Hessen, Dag Olav
Formato: Online Artículo Texto
Lenguaje:English
Publicado: PeerJ Inc. 2017
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5590550/
https://www.ncbi.nlm.nih.gov/pubmed/28890852
http://dx.doi.org/10.7717/peerj.3743
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author Skau, Lars Fredrik
Andersen, Tom
Thrane, Jan-Erik
Hessen, Dag Olav
author_facet Skau, Lars Fredrik
Andersen, Tom
Thrane, Jan-Erik
Hessen, Dag Olav
author_sort Skau, Lars Fredrik
collection PubMed
description Temperature and nutrients are key factors affecting the growth, cell size, and physiology of marine phytoplankton. In the ocean, temperature and nutrient availability often co-vary because temperature drives vertical stratification, which further controls nutrient upwelling. This makes it difficult to disentangle the effects of temperature and nutrients on phytoplankton purely from observational studies. In this study, we carried out a factorial experiment crossing two temperatures (13°and 19°C) with two growth regimes (P-limited, semi-continuous batch cultures [“−P”] and nutrient replete batch cultures in turbidostat mode [“+P”]) for three species of common marine haptophytes (Emiliania huxleyi, Chrysochromulina rotalis and Prymnesium polylepis) to address the effects of temperature and nutrient limitation on elemental content and stoichiometry (C:N:P), total RNA, cell size, and growth rate. We found that the main gradient in elemental content and RNA largely was related to nutrient regime and the resulting differences in growth rate and degree of P-limitation, and observed reduced cell volume-specific content of P and RNA (but also N and C in most cases) and higher N:P and C:P in the slow growing −P cultures compared to the fast growing +P cultures. P-limited cells also tended to be larger than nutrient replete cells. Contrary to other recent studies, we found lower N:P and C:P ratios at high temperature. Overall, elemental content and RNA increased with temperature, especially in the nutrient replete cultures. Notably, however, temperature had a weaker–and in some cases a negative–effect on elemental content and RNA under P-limitation. This interaction indicates that the effect of temperature on cellular composition may differ between nutrient replete and nutrient limited conditions, where cellular uptake and storage of excess nutrients may overshadow changes in resource allocation among the non-storage fractions of biomass (e.g. P-rich ribosomes and N-rich proteins). Cell size decreased at high temperature, which is in accordance with general observations.
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spelling pubmed-55905502017-09-08 Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes Skau, Lars Fredrik Andersen, Tom Thrane, Jan-Erik Hessen, Dag Olav PeerJ Ecology Temperature and nutrients are key factors affecting the growth, cell size, and physiology of marine phytoplankton. In the ocean, temperature and nutrient availability often co-vary because temperature drives vertical stratification, which further controls nutrient upwelling. This makes it difficult to disentangle the effects of temperature and nutrients on phytoplankton purely from observational studies. In this study, we carried out a factorial experiment crossing two temperatures (13°and 19°C) with two growth regimes (P-limited, semi-continuous batch cultures [“−P”] and nutrient replete batch cultures in turbidostat mode [“+P”]) for three species of common marine haptophytes (Emiliania huxleyi, Chrysochromulina rotalis and Prymnesium polylepis) to address the effects of temperature and nutrient limitation on elemental content and stoichiometry (C:N:P), total RNA, cell size, and growth rate. We found that the main gradient in elemental content and RNA largely was related to nutrient regime and the resulting differences in growth rate and degree of P-limitation, and observed reduced cell volume-specific content of P and RNA (but also N and C in most cases) and higher N:P and C:P in the slow growing −P cultures compared to the fast growing +P cultures. P-limited cells also tended to be larger than nutrient replete cells. Contrary to other recent studies, we found lower N:P and C:P ratios at high temperature. Overall, elemental content and RNA increased with temperature, especially in the nutrient replete cultures. Notably, however, temperature had a weaker–and in some cases a negative–effect on elemental content and RNA under P-limitation. This interaction indicates that the effect of temperature on cellular composition may differ between nutrient replete and nutrient limited conditions, where cellular uptake and storage of excess nutrients may overshadow changes in resource allocation among the non-storage fractions of biomass (e.g. P-rich ribosomes and N-rich proteins). Cell size decreased at high temperature, which is in accordance with general observations. PeerJ Inc. 2017-09-05 /pmc/articles/PMC5590550/ /pubmed/28890852 http://dx.doi.org/10.7717/peerj.3743 Text en ©2017 Skau et al. http://creativecommons.org/licenses/by/4.0/ This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ) and either DOI or URL of the article must be cited.
spellingShingle Ecology
Skau, Lars Fredrik
Andersen, Tom
Thrane, Jan-Erik
Hessen, Dag Olav
Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes
title Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes
title_full Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes
title_fullStr Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes
title_full_unstemmed Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes
title_short Growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes
title_sort growth, stoichiometry and cell size; temperature and nutrient responses in haptophytes
topic Ecology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5590550/
https://www.ncbi.nlm.nih.gov/pubmed/28890852
http://dx.doi.org/10.7717/peerj.3743
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