Phytoplankton composition derived from CHEMTAX along 10°E during POLARSTERN cruise ANT-XXVIII/3, Jan-March 2012 ...

• Main Authors: Cheah, Wee, Soppa, Mariana A, Wiegmann, Sonja, Ossebaar, Sharyn, Laglera, Luis Miguel, Strass, Volker H, Santos-Echeandía, Juan, Hoppema, Mario, Wolf-Gladrow, Dieter A, Bracher, Astrid
• Format: Dataset
• Language: English
• Published: PANGAEA 2016
• Subjects: Event label; Date/Time of event; Latitude of event; Longitude of event; Elevation of event; DEPTH, water; Cyanobacteria; Chlorophytes; Prasinophytes; Cryptophytes; Diatoms; Dinoflagellates; Haptophytes; CTD/Rosette; In situ pump; CHEMTAX Lewitus et al., 2005; ANT-XXVIII/3; Polarstern; Antarc*; Antarctic
• Online Access: https://dx.doi.org/10.1594/pangaea.866372; https://doi.pangaea.de/10.1594/PANGAEA.866372

Phytoplankton community structure and their physiological response in the vicinity of the Antarctic Polar Front (APF; 44°S to 53°S, centred at 10°E) were investigated as part of the ANT-XXVIII/3 Eddy-Pump cruise conducted in austral summer 2012. Our results show that under iron-limited (< 0.3 µmol/m**3) conditions, high total chlorophyll-a (TChl-a) concentrations (> 0.6 mg/m**3) can be observed at stations with deep mixed layer (> 60 m) across the APF. In contrast, light was excessive at stations with shallower mixed layer and phytoplankton were producing higher amounts of photoprotective pigments, diadinoxanthin (DD) and diatoxanthin (DT), at the expense of TChl-a, resulting in higher ratios of (DD+DT)/ TChl-a. North of the APF, significantly lower silicic acid (Si(OH)4) concentrations (< 2 mmol/m**3) lead to the domination of nanophytoplankton consisting mostly of haptophytes, which produced higher ratios of (DD+DT)/TChl-a under relatively low irradiance conditions. The Si(OH)4 replete (> 5 ... : Supplement to: Cheah, Wee; Soppa, Mariana A; Wiegmann, Sonja; Ossebaar, Sharyn; Laglera, Luis Miguel; Strass, Volker H; Santos-Echeandía, Juan; Hoppema, Mario; Wolf-Gladrow, Dieter A; Bracher, Astrid (2016): Importance of deep mixing and silicic acid in regulating phytoplankton biomass and community in the iron-limited Antarctic Polar Front region in summer. Deep Sea Research Part II: Topical Studies in Oceanography, 12 pp ...