Biotic water-column characteristics (Chla, Phaeo, TC, TN, δ13C, δ15N) at four stations in the Weddell Sea (POLARSTERN cruise PS 118, February - April 2019)

This dataset contains biotic data from water-column samples taken with Niskin bottles mounted on a CTD rosette from four sites in the northwestern Weddell Sea. Data are provided for water-column pigments (chlorophyll a and phaeopigment content through fluorometry), total carbon (TC), total nitrogen (TN) and stable isotope values of carbon and nitrogen (δ13C, δ15N) from the chlorophyll maximum (Cmax, defined as the water depth with maximum fluorescence detected during in-situ profiles) and close to the sea bottom. Water was filtered onto glass fiber filters (GF/C for pigments, pre-combusted GF/F for C and N analyses) and stored at -80°C prior to analysis. Same sampling and measurement procedure as for PS 96 samples were applied, detailed methods are described in Säring et al. (2022), except for stable isotopes: Flash combustion in a Flash 2000 (Thermo) elemental analyser to a Delta V advantage (Thermo) isotope ratio masspectrometer. δ values are reported relative to atmospheric N₂ (δ15N) and Vienna PeeDee Belemnite (δ13C). Reference materials for stable isotope analysis: IAEA-N1, IAEA-N2, IAEA-N3, NBS 22, IAEA-CH-3 and IAEA-CH-6; calibration material: Acetanilide (Merck). The analytical precision for both stable isotope ratios was <±0.2‰. Samples were not acidified to avoid loss of material. We assumed low inorganic carbon content in the water column for our analyses. This data table is part of a study analyzing the role of environmental parameters for meio- and macrofaunal community compositions and polychaete community distribution patterns (see "Supplement to", "Related to" and "Further details" below).