TY - JOUR
T1 - Allometry of carbon and nitrogen content and growth rate in a diverse range of coccolithophores
AU - Villiot, Naomi
AU - Poulton, Alex J.
AU - Butcher, Elizabeth T.
AU - Daniels, Lucie R.
AU - Coggins, Aimee
N1 - Funding Information:
This work was supported by the School of Energy, Geoscience, Infrastructure and Society at Heriot-Watt University through a James Watt scholarship toN.V.; and the Marine Alliance for Science and Technology for Scotland through a small grant funding (SG509).
Publisher Copyright:
© 2021 The Author(s) 2021. Published by Oxford University Press.
PY - 2021/7
Y1 - 2021/7
N2 - As both photoautotrophs and calcifiers, coccolithophores play important roles in ecosystems and biogeochemical cycles. Though some species form blooms in high-latitude waters, low-latitude communities exhibit high diversity and niche diversification. Despite such diversity, our understanding of the clade relies on knowledge of Emiliana huxleyi. To address this, we examine carbon (C) and nitrogen (N) content of strains (n = 9) from the main families of the calcifying Haptophyceae, as well as allometry and cell size frequency across extant species. Coccolithophore cell size is constrained, with ~71% of 159 species smaller than 10 μm in diameter. Growth rates scale with cell biovolume (μ = 1.83 × cell volume−0.19), with an exponent close to metabolic theory. Organic carbon (C) per cell is lower than for other phytoplankton, providing a coccolithophore-specific relationship between cell organic C content and biovolume (pg C cell−1 = 0.30 × cell volume0.70). Organic C to N ratios (~8.3 mol:mol) are similar to other phytoplankton, implying little additional N cost for calcification and efficient retention and recycling of cell N. Our results support observations that coccolithophores are efficient competitors in low-nutrient conditions, able to photosynthesize, calcify and run the routine metabolic machinery necessary without any additional need for N relative to noncalcifying algae.
AB - As both photoautotrophs and calcifiers, coccolithophores play important roles in ecosystems and biogeochemical cycles. Though some species form blooms in high-latitude waters, low-latitude communities exhibit high diversity and niche diversification. Despite such diversity, our understanding of the clade relies on knowledge of Emiliana huxleyi. To address this, we examine carbon (C) and nitrogen (N) content of strains (n = 9) from the main families of the calcifying Haptophyceae, as well as allometry and cell size frequency across extant species. Coccolithophore cell size is constrained, with ~71% of 159 species smaller than 10 μm in diameter. Growth rates scale with cell biovolume (μ = 1.83 × cell volume−0.19), with an exponent close to metabolic theory. Organic carbon (C) per cell is lower than for other phytoplankton, providing a coccolithophore-specific relationship between cell organic C content and biovolume (pg C cell−1 = 0.30 × cell volume0.70). Organic C to N ratios (~8.3 mol:mol) are similar to other phytoplankton, implying little additional N cost for calcification and efficient retention and recycling of cell N. Our results support observations that coccolithophores are efficient competitors in low-nutrient conditions, able to photosynthesize, calcify and run the routine metabolic machinery necessary without any additional need for N relative to noncalcifying algae.
KW - coccolithophores
KW - comparative biochemistry
KW - ecology
KW - elemental stoichiometry
UR - http://www.scopus.com/inward/record.url?scp=85112343846&partnerID=8YFLogxK
U2 - 10.1093/plankt/fbab038
DO - 10.1093/plankt/fbab038
M3 - Article
C2 - 34326702
SN - 0142-7873
VL - 43
SP - 511
EP - 526
JO - Journal of Plankton Research
JF - Journal of Plankton Research
IS - 4
ER -