UNDER EMBARGO - This dataset is part of BE/2023 sampling campagn in SW Greenland fjords (Igaliku and Tunulliarfik). Pelagic community was analysed using Imaging Flow Cytometry (iFCM) with an ImageStream®X Mk II. Cells were grouped into functional size classes—pico-, nano- and microplankton—according to measured cell length. Cells lacking chlorophyll autofluorescence were classified as heterotrophic or chemotrophic organisms, including heterotrophic picoplankton/bacteria (HP; ≤2 µm) and heterotrophic nanoplankton (HN; 2–20 µm). No larger heterotrophs (>20 µm) were visually detected. Autofluorescent cells were considered phototrophic, although this fraction may also include mixotrophic taxa, and comprised picophytoplankton (AP; ≤2 µm), nanophytoplankton (AN; 2–20 µm), and microphytoplankton (AMicro; 20–100 µm). To estimate the biovolume of each plankton class, the two-dimensional cell surface area measured by the IDEAS® imaging software was multiplied by the mean cell width, assuming that cell width approximates the third spatial dimension. Carbon biomass was subsequently derived from biovolume using established carbon–volume relationships. For the HP fraction, carbon content was estimated using the bacterial conversion proposed by Romanova and Sazhin (2010), where volume is expressed in µm³. Although the HP fraction may also include heterotrophic picoeukaryotes, and its biomass may therefore be partly underestimated, this conversion was applied because the fraction was assumed to be numerically dominated by bacteria. For the other protist groups, carbon biomass was derived following Menden-Deuer and Lessard (2000). Carbon values were converted from pg C cell⁻¹ to carbon biomass (µg C L⁻¹) based on cell abundance.

UNDER EMBARGO - This dataset is part of BE/2023 sampling campagn in SW Greenland fjords (Igaliku and Tunulliarfik). Samples for DNA extraction were collected along fjord transects at several depths of the water column. The focus of the study was to determine the taxonomical composotion of bacterial community in two Arctic fjords.

This dataset contains marine organic matter source samples, artificial mixtures of known composition, and compound-specific nitrogen stable isotope data of amino acids (δ¹⁵N-AA). Source materials include phytoplankton, zooplankton, and faecal pellets from the marine fouling species Mytilus edulis and Metridium senile. Samples were collected and processed in the laboratory under controlled conditions. Artificial mixtures were prepared by combining source materials in defined proportions to generate experimental samples representing multiple marine organic matter source combinations. Metadata describing sample collection, preparation, and mixture composition are included. Compound-specific nitrogen isotope ratios of individual amino acids were measured using stable isotope analysis. The dataset includes isotopic measurements for all source samples and artificial mixtures, along with associated metadata required to document sampling, laboratory preparation, and analytical procedures.

UNDER EMBARGO - This dataset is part of BE/2023 sampling campagn in SW Greenland fjords (Igaliku and Tunulliarfik) and includes measurements of pelagic community respiration to assess microbial metabolic activity across fjords with contrasting glacial influence and seasonal conditions. Pelagic community respiration rates were determined following Martínez-García et al. (2009): seawater samples (200 mL; n = 4 replicates) were incubated with INT (final concentration 0.8 mM). Control samples were fixed with formaldehyde (2% final concentration) prior to incubation. After incubation, samples were filtered (0.2 μm), and the reduced INT (formazan) retained on filters was extracted with 1-propanol. Formazan concentration was determined spectrophotometrically at 485 nm, subtracting non-metabolic absorbance from controls. INT reduction rates were calculated as μmol INTf L⁻¹ h⁻¹ and subsequently converted to O₂ consumption rates (μmol O₂ L⁻¹ h⁻¹) following Martínez-García et al. (2019).

The law of 13 June 1969 defines “Belgian Continental Shelf” as follows: the seabed and the subsoil of the marine areas adjacent to the Belgian coast but beyond the Belgian territorial sea.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 1, criterion 2. The Raja clavata dataset describes the results of the Offshore Beam Trawl Surveys (BTS) in the Belgian part of the North Sea (BPNS) between 2010 and 2017. Occurrences of Raja Clavata, along with dates and locations, are reported. The codes used in the attached file are based on the ICES DATRAS (Database of Trawl Surveys) standard. The seabirds dataset describes the density of seabirds (N birds/km) observed in the BPNS between 1987 and 2016 (three surveys a year).

UNDER EMBARGO - This dataset originates from the BE/2023 sampling campaign conducted in southwest Greenland fjords (Igaliku and Tunulliarfik) and quantifies grazing impacts by micro- and mesozooplankton on phytoplankton and heterotrophic microbial communities (including bacteria) in two fjord systems characterized by contrasting glacial regimes. Grazing and microbial growth rates were estimated using two-point dilution experiments (two-point dilution experiments), alongside experiments assessing mesozooplankton and copepod grazing on both phytoplankton and microzooplankton. Community responses were resolved using imaging flow cytometry, enabling the identification of plankton functional groups (autotrophic, mixotrophic, and heterotrophic) and size classes. The dataset also includes measurements of chlorophyll a variability determined by high-performance liquid chromatography. Overall, the dataset supports analyses of trophic interactions and grazing dynamics across the microbial food web under differing glacier-influenced environmental conditions.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 8, criterion 3. This dataset gives an overview of the observed slicks during aerial survey operations of the Belgian part of the North Sea (2011-2016). Related to significant acute pollution, it includes the observations linked to the Flinterstar incident in 2015. Besides this, all observations of illegal discharges of MARPOL (International Convention for the Prevention of Pollution from Ships) annex I and II substances are included as an additional dataset.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 8, criterion 2. This dataset contains measurements on the 7-Ethoxyresorufin-O-deethylase (EROD) activity in Limanda limanda, Imposex (OTIN in Mytilus edulis), fish diseases and counts of oiled common guillemots in the Belgian part of the North Sea.

UNDER EMBARGO - This dataset contains seasonal physiological measurements from controlled laboratory experiments on two dominant suspension-feeding species expected to colonise floating offshore structures: the blue mussel (Mytilus edulis; AphiaID 140480) and the wrinkled barnacle (Balanus crenatus; AphiaID 106215). The measured parameters include clearance rates, respiration rates, faecal pellet production rates, and faecal pellet sinking velocities. Mussels were collected from an aquaculture longline at the Westdiep SeaFarm, while barnacles were manually retrieved from the intertidal beachhead at Raversijde (Oostende, Belgium). All experiments were conducted using natural seawater collected from offshore sites in the Belgian part of the North Sea. Measurements were repeated across multiple seasons to capture temporal variability in physiological performance. The dataset was produced within the SWiM and EcoMPV projects and is suitable for reuse in ecosystem and biogeochemical modelling, including simulations of phytoplankton dynamics associated with large-scale offshore marine photovoltaic (MPV) developments.