Adaptive evolution in the coccolithophore Gephyrocapsa oceanica following 1,000 generations of selection under elevated CO 2

Abstract Coccolithophores are important oceanic primary producers not only in terms of photosynthesis but also because they produce calcite plates called coccoliths. Ongoing ocean acidification associated with changing seawater carbonate chemistry may impair calcification and other metabolic functio...

Full description

Bibliographic Details
Published in:Global Change Biology
Main Authors: Tong, Shanying, Gao, Kunshan, Hutchins, David A.
Other Authors: National Science Foundation, National Natural Science Foundation of China
Format: Article in Journal/Newspaper
Language:English
Published: Wiley 2018
Subjects:
Online Access:http://dx.doi.org/10.1111/gcb.14065
https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fgcb.14065
https://onlinelibrary.wiley.com/doi/pdf/10.1111/gcb.14065
https://onlinelibrary.wiley.com/doi/full-xml/10.1111/gcb.14065
http://api.wiley.com/onlinelibrary/chorus/v1/articles/10.1111%2Fgcb.14065
Description
Summary:Abstract Coccolithophores are important oceanic primary producers not only in terms of photosynthesis but also because they produce calcite plates called coccoliths. Ongoing ocean acidification associated with changing seawater carbonate chemistry may impair calcification and other metabolic functions in coccolithophores. While short‐term ocean acidification effects on calcification and other properties have been examined in a variety of coccolithophore species, long‐term adaptive responses have scarcely been documented, other than for the single species Emiliania huxleyi . Here, we investigated the effects of ocean acidification on another ecologically important coccolithophore species, Gephyrocapsa oceanica, following 1,000 generations of growth under elevated CO 2 conditions (1,000 μatm). High CO 2 ‐selected populations exhibited reduced growth rates and enhanced particulate organic carbon ( POC ) and nitrogen ( PON ) production, relative to populations selected under ambient CO 2 (400 μatm). Particulate inorganic carbon ( PIC ) and PIC / POC ratios decreased progressively throughout the selection period in high CO 2 ‐selected cell lines. All of these trait changes persisted when high CO 2 ‐grown populations were moved back to ambient CO 2 conditions for about 10 generations. The results suggest that the calcification of some coccolithophores may be more heavily impaired by ocean acidification than previously predicted based on short‐term studies, with potentially large implications for the ocean's carbon cycle under accelerating anthropogenic influences.