Description
Summary:The minicosm experimental design measured the microbial community growth in six unreplicated fCO2 treatments. Therefore, sub-samples from each minicosm were within-treatment pseudoreplicates and thus, results of statistical analysis must be interpreted conservatively. This data set was collected from a ocean acidification minicosm experiment performed at Davis Station, Antarctica during the 2014/15 summer season. It includes: - description of methods for all data collection and analyses. - flow cytometry counts; autotrophic cells, heterotrophic nanoflagellates, and prokaryotes One community-level study has been performed in Antarctic waters on a natural coastal marine microbial community at Davis Station, Antarctica during the 2008/09 summer season. This study in Prydz Bay, East Antarctica reported declines in primary and bacterial productivity when CO2 concentration exceeded 780 micro atm. A shift in community composition was also observed, with increased abundance of small picoeukaryotes and a decline in large diatoms. Based on the results of this previous study, a natural community of Antarctic marine microbes from Prydz Bay, East Antarctica were exposed to a range of CO2 concentrations in 650 l minicosms to simulate possible future ocean conditions up to the year ∼2200. The abundance of autotrophic cells, heterotrophic nanoflagellates, and prokaryotes was examined at CO2 concentrations between 343 to 1641 μatm to determine whether tipping points existed, above which CO2 concentration changed the abundance of the microbial community.