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Updated: Jul 5, 2026
15:39
Characterization of Calcification Events Using Live Optical and Electron Microscopy Techniques in a Marine Tubeworm
Published on: February 28, 2017
Phytoplankton calcification in a high-CO2 world
M Debora Iglesias-Rodriguez1, Paul R Halloran, Rosalind E M Rickaby
1National Oceanography Centre, Southampton, University of Southampton Waterfront Campus, European Way, Southampton SO14 3ZH, UK.
Science (New York, N.Y.)
|April 19, 2008
Summary
Rising carbon dioxide levels unexpectedly boost calcification in coccolithophores, key marine calcium carbonate producers. This finding challenges assumptions about ocean acidification impacts on these vital organisms.
Area of Science:
- Marine Biology
- Oceanography
- Biogeochemistry
Background:
- Ocean acidification, driven by increased atmospheric CO2, is generally predicted to inhibit marine calcification.
- Coccolithophores are significant contributors to marine calcium carbonate (CaCO3) production, accounting for approximately one-third of global totals.
- Understanding coccolithophore responses to changing ocean chemistry is crucial for predicting future ocean dynamics.
Purpose of the Study:
- To investigate the impact of elevated CO2 partial pressures on the calcification and primary production of Emiliania huxleyi.
- To assess whether field observations align with laboratory findings regarding coccolithophore responses to rising CO2.
Main Methods:
- Laboratory experiments exposing Emiliania huxleyi to varying CO2 partial pressures.
- Analysis of deep-ocean sediment cores to reconstruct historical coccolith mass changes over the past 220 years.
Main Results:
- Laboratory results showed a significant increase in calcification and net primary production in Emiliania huxleyi under high CO2 conditions.
- Field evidence indicated a 40% rise in average coccolith mass over the last 220 years, consistent with laboratory findings.
- Coccolithophores are actively responding to increasing atmospheric CO2 levels.
Conclusions:
- Contrary to expectations, Emiliania huxleyi demonstrates enhanced calcification with rising CO2.
- The observed historical increase in coccolith mass supports the conclusion that coccolithophores are adapting to changing ocean conditions.
- These findings necessitate revisions in biogeochemical models predicting future ocean and climate scenarios.
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