Meakin NG, Wyman M
picoeukaryotes, Micromonas, Bathycoccus, RubisCO, 11 m3, mesocosm, Bergen, Espegrend, Norway, acidification
Rapid shifts in picoeukaryote community structure were observed during a CO2 perturbationexperiment in which we followed the development of phytoplankton blooms in nutrient-amendedmesocosms under the present day or predicted future atmospheric pCO2 (750 latm, seawater pH7.8). Analysis of rbcL clone libraries (encoding the large subunit of RubisCO) and specificquantitative PCR assays showed that two prasinophytes closely related to Micromonas pusilla andBathycoccus prasinos were present, but responded very differently to high CO2/acidification. Wefound that the abundance of Micromonas-like phylotypes was significantly higher (420-fold) underelevated CO2/low pH, whereas the Bathycoccus-like phylotypes were more evenly distributedbetween treatments and dominated the prasinophyte community under ambient conditions.The ISME Journal (2011) 5, 1397–1405; doi:10.1038/ismej.2011.18; published online 17 March 2011Subject Category: microbial population and community ecology