DataSheet_1_Spatial and temporal variability of phytoplankton photophysiology in the Atlantic Southern Ocean.docx

• Main Authors: Asmita Singh, Sandy J. Thomalla, Susanne Fietz, Thomas J. Ryan-Keogh
• Format: Dataset
• Language: unknown
• Published: 2022
• Subjects: Oceanography; Marine Biology; Marine Geoscience; Biological Oceanography; Chemical Oceanography; Physical Oceanography; Marine Engineering; Fast Induction and Relaxation (FIRe) fluorometry; fluorescence; physical and biogeochemical parameters; phytoplankton photophysiology; photosynthetic efficiency; zonal variability; inter-annual variability; intra-seasonal variability; Antarc*; Antarctic; Southern Ocean
• Online Access: https://doi.org/10.3389/fmars.2022.912856.s001; https://figshare.com/articles/dataset/DataSheet_1_Spatial_and_temporal_variability_of_phytoplankton_photophysiology_in_the_Atlantic_Southern_Ocean_docx/21314955

Active chlorophyll-a fluorescence was measured during five summer research cruises (2008 – 2016), spanning the Atlantic sector of the Southern Ocean. This unique data set provides information for assessing zonal, inter-annual and intra-seasonal variability (early versus late summer) of photosynthetic efficiency (F v /F m ). The zonal variability of F v /F m showed a typical latitudinal decline from a maximum in the Polar Frontal Zone (PFZ) (0.24±0.03) to a minimum in the Southern Antarctic Circumpolar Current Zone (SACCZ) (0.18±0.07). The inter-annual variability in F v /F m (between each cruise) was the highest in the SACCZ, while the Antarctic Zone (AZ) exhibited low inter-annual variability. Intra-seasonal variability between the zones was limited to a significantly higher mean F v /F m in the PFZ and AZ in early summer compared to late summer. Intra-seasonal variability between the cruises was, however, inconsistent as higher mean F v /F m in early summer were seen during some years as opposed to others. Ancillary physical and biogeochemical parameters were also assessed to investigate potential direct and indirect drivers of co-variability with F v /F m through a series of statistical t-tests, where significant differences in F v /F m were used as focus points to interrogate the plausibility of co-variance. Inter-zonal variability of surface seawater temperature (SST) and Silicate:Phosphate (Si:P) ratios were highlighted as co-varying with F v /F m in all zones, whilst community structure played an indirect role in some instances. Similarly, inter-annual variability in F v /F m co-varied with SST, Nitrate:Phosphate (N:P) and Si:P ratios in the PFZ, AZ and SACCZ, while community structure influenced inter-annual variability in the PFZ and SACCZ. Intra-seasonal variability in F v /F m was linked to all the ancillary parameters, except community structure in the AZ, whilst different ancillary parameters dominated differences during each of the cruises. These results were further scrutinized with a Principal ...