Description: This dataset contains biotic and abiotic data from water-column samples taken with Niskin bottles mounted on the CTD rosette from 14 sites in the Weddell Sea (mostly South-Eastern). Data are provided for water-column pigments (chlorophyll a and phaeopigment content through fluorometry), total carbon (TC) and 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, combusted GF/F for C and N analyses) and stored at -80°C prior to analysis. Detailed methods are described in Säring et al. (submitted) 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 larger study analysing the role of environmental parameters for meio- and macrofaunal community composition (see Related to below).

Description: This dataset contains abiotic and biotic data from sediment samples from nine sites in the Weddell Sea (mostly South-Eastern). Data are provided for sediment pigments (chlorophyll a and phaeopigment content through fluorometry), total organic carbon (TOC), total nitrogen (TN), stable isotope values of carbon and nitrogen (δ13C, δ15N) and grain size (silt&clay 〈 32 µm, very fine sand 63–125 µm sand, fine sand 125–250 µm, medium sand 250–500 µm, coarse sand 500–1000 µm, larger coarse sand 〉 1000 µm). Before the TOC and carbon isotope analysis the sediment samples were acidified to eliminate inorganic carbon. A minimum of three replicate samples (cores) were collected using a MUC10 multicorer or giant box corer. Sediment cores were subsampled with a 60-ml syringe (inner diameter 2.7 cm) for stations 017, 026, 061, 072, and with a 10-ml syringe (inner diameter 1 cm) for stations 001, 037, 048, 104, 115. Subsamples were sliced in 1-cm steps down to 5 cm depth. Detailed methods are described in Säring et al. (submitted) 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‰. Cores with the label -e (Environment) were only used to collect the above data. Environmental and fauna data were collected from cores with the label -i (Incubation). This data table is part of a larger study analysing the role of environmental parameters for meio- and macrofaunal community composition (see Related to below).

Description: This dataset contains abiotic and biotic data from sediment samples from four sites in the northwestern Weddell Sea. Data are provided for sediment pigments (chlorophyll a and phaeopigment content through fluorometry), total organic carbon (TOC), total nitrogen (TN), stable isotope values of carbon and nitrogen (δ13C, δ15N) and grain size (silt&clay 〈 32 µm, very fine sand 63–125 µm, fine sand 125–250 µm, medium sand 250–500 µm, coarse sand 500–1000 µm, larger coarse sand 〉 1000 µm). A minimum of three replicate samples (cores) were collected using a MUC10 multicorer. All sediment cores were subsampled with a 10-ml syringe (inner diameter 1 cm). Subsamples were sliced in 1-cm steps down to 5 cm depth. The same sampling and measurements as for PS 96 were carried out (see below "Related to". Prior to TOC and δ13C analysis sediment samples were acidified to eliminate inorganic carbon. 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‰. Cores with the label -e (Environment) were only used to collect the above data. Environmental, fauna and benthic boundary flux data were collected from cores with the label -i (Incubation). This data table is part of studies 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).

Description: The Amazon River is known as a region of intense biochemical reactivity. As a result of increased anthropogenic impacts in its catchment (e.g. population growth, agriculture, and deforestation), The Amazon River is undergoing fundamental changes. The RV METEOR cruise M174 (doi:10.1594/PANGAEA.935041) aimed to provide an integrated overview of nitrogen cycling processes in areas influenced by the Amazon River, which is crucial to estimate the ecosystem's health and productivity. During this cruise, six stations were visited to explore the significance of denitrification as a dominant pathway in the watercolumn of the Amazon and Pará estuaries. This dataset presents the stable isotopic composition of nitrate (d15N- d18O-NO3), as well as d2H and d18O of ambient water.