Concentrations of chlorophyll a, phaeopigments, and particulate matter during the iron fertilization experiment EIFEX in 2004

• Main Authors: Klaas, Christine, Assmy, Philipp, Benner, Ina, Berg, Gry Mine, Mills, Matthew M, Passow, Uta, Schmidt, Maike M, Terbrüggen, Anja, Wolf-Gladrow, Dieter A, Smetacek, Victor
• Format: Dataset
• Language: English
• Published: PANGAEA 2023
• Subjects: ANT XXI/3; ANT-XXI/3; Biogenic silica; Carbon; organic; particulate; Cast number; Chlorophyll a; Colorimetry according to Hansen and Koroleff (1999); CTD/Rosette; CTD-RO; DATE/TIME; DEPTH; water; dissolved in organic carbon (DIC); Dissolved Organic Matter; Duration; number of days; Elemental analyzer; Decarbonation and preservation method according to Lorrain et al. (2003); Event label; Fluorometer; Turner Designs; 10-AU; According to Knap et al. (1996); LATITUDE; LONGITUDE; Nitrogen; particulate organic matter; Phaeopigments; Phosphorus; Polarstern; Position; PS65/424-3; PS65/426-1; PS65/427-1; PS65/452-1; PS65/464-1; PS65/466-2; PS65/470-1; PS65/474-1; PS65/508-2; PS65/509-1; PS65/511-1; PS65/513-3; PS65/514-2; Antarc*; Antarctic
• Online Access: https://doi.pangaea.de/10.1594/PANGAEA.954829; https://doi.org/10.1594/PANGAEA.954829

Here we present concentrations of chlorophyll a, phaeopigments, particulate organic carbon and nitrogen from water samples collected at discrete depths with a CTD-rosette during the European Iron Fertilization Experiment (EIFEX). The experiment was carried out from February 11 to March 20, 2004 in the 60-km diameter, rotating core of an eddy, formed by a meander of the Antarctic Polar Front (centred at around 49°10' S and 2°10' E). Samples were taken within the eddy inside and outside the fertilized patch, and in a few cases outside the eddy.Chlorophyll concentrations were determined by fluorometry using a Turner Design Model 10-AU digital fluorometer. Sampling, measurements and calibration of the fluorometer was carried out following the JGOFS protocol procedure (Knap et al, 1996). Results of the fluorometer calibration diverged by 5% between beginning and end of the cruise. Chlorophyll a content was calculated using average parameter values from the two calibrations. Measurement uncertainty was estimated from triplicate water samples taken from depths ranging between 10 and 100 m depth and averaged 5% of measured values. Samples for particulate organic carbon and nitrogen (POC and PON) were filtered onto precombusted Whatman GF/F filters and processed following recommendations by Lorrain et al. (2003). Samples were measured independently on three different analysers: a CN2500 CHN Analyser (Thermo Finnigan MAT) coupled to a Delta+ mass spectrometer (Thermo Finnigan MAT) via Conflo II interface (Thermo Finnigan MAT), a Carlo-Erba NA-1500 Series II elemental analyzer coupled to a Finnegan Delta+ mass spectrometer and a Euro EA Elemental Analyser. Differences due to methods were within the range of measurement variability (below 2%). The particulate organic phosphorus (POP) content was determined colorimetrically using the method from Hansen and Koroleff (1999; measurement variability 4%). Biogenic silica (BSi) was measured following the wet alkaline digestion method according to Müller and Schneider (1993; ...