Beach Litter count data collected across 10 beaches of the Belgian coast in 2023 and 2024 by volunteers of the citizen science association Proper Strand Lopers. One of the key indicators of abundance, composition and trends of litter in the marine environment is the amount on beaches. OSPAR monitors litter on 100m stretches at over 70 beaches in the North-East Atlantic following common monitoring guidelines. The monitoring records litter in 112 predefined litter items in 11 types: Plastic / polystyrene, Metal, Paper and cardboard, Wood, Sanitary waste, Cloth, Rubber, Glass, Pottery/ceramics, Medical waste and Faeces.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 7, criterion 1. This dataset describes the impact of an offshore windmills farm on the hydrodynamics in the Belgian part of the North Sea (BPNS). Originally, it is a NetCDF file with the results of the reference simulation made with the COHERENS (COupled Hydrodynamical Ecological model for REgioNal Shelf seas) hydrodynamic model only forced by tides (no wind effect). Model resolution : ~ 12.5m. It contains both the reference situation which is a simulation without any windmill and the modeling result of the influence by the windmills on the hydrodynamic in the BPNS. The dataset contains the results on the most inner nested grid level for one reference spring-neap cycle: - hourly sea surface elevation - hourly bottom shear stress - hourly 3D horizontal velocity components (u,v) - hourly 3D eddy viscosity - time-averaged bottom shear stress over the reference spring-neap cycle - percentile 90 of the bottom shear stress for the reference spring-neap cycle - percentile 90 of the specific kinetic energy at the sea bed - accumulated time during which sedimentation processes are dominant - accumulated time during which re-suspension processes are dominant.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 4, criterion 2. Three distinct datasets are published for this criterion.'Occurrence of breeding seabirds' describes the observation of eight seabird species (Common tern, Black-headed Gull, Herring Gull, Common Gull, Small Black-backed Gull, Yellow-legged gull, Big Stern and Little Stern) on the Belgian coast between 1992 and 2015. 'Density of seabirds' describes the density of seabirds (N birds/km) observed at large in the Belgian part of the North Sea between 1987 and 2016 (three surveys a year). Thirteen species are monitored and the evolution of each species density is shown as diagrams.'Occurrence of important benthic species' describes the results of Van Veen sampling campaigns performed between 2009 and 2014 in the Belgian part of the North Sea. Benthic species are counted and identified (e.g. Annelida, Echinodermata,..).

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 protist community in two Arctic fjords.

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.

UNDER EMBARGO - This dataset is part of BE/2023 sampling campagn in SW Greenland fjords (Igaliku and Tunulliarfik). The dataset reports the final concentrations (μg L⁻¹) of each detected photosynthetic pigment, used to infer phytoplankton functional groups and compare community composition across fjords with differing glacial influence and between seasons (spring–summer). For pigment analysis, seawater volumes ranging from 700 mL to 1 L were filtered onto 25-mm diameter Whatman GF/F filters and immediately stored at -80°C until further analysis. Pigments were extracted using 90% acetone and analysed by High-Performance Liquid Chromatography (HPLC) following the method of Van Heukelem and Thomas (2001). Calibration was performed using pigment standards from DHI Water and Environment (Hørsholm, Denmark). In the dataset is indicated the final consentration (μg/L) of each detected photosyntetic pigment.

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).

UNDER EMBARGO - 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.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 5, criterion 1. This dataset contains the nutrient concentrations (ammonia, nitrate, nitrite, total nitrogen, phosphorus) measured on water samples taken in the BPNS between 2011 and 2016. The analysis of nutrients (N and P) is ensured by the national monitoring programme at ten sampling locations that are representative for the surrounding water masses. Based on all 2011-2016 results, the relationship with the salt content was calculated and, for each year, the value derived corresponding to a salt content of 33.5. The surface of the area where the nutrient concentrations exceed the respective thresholds was calculated on the basis of the relationship with the winter salt content and a climatology of the spatial distribution of the salt content (see annex D5 of the Belgian MSFD report). The resulting maps give a good overview of nutrient concentrations in the Belgian zone. In order to take into account the coastal-sea gradient and to illustrate the temporal trends in detail, the concentrations were also evaluated in three different areas of the BPNS: the coastal zone, the territorial zone and the open-sea zone. The long-term trends of nutrient concentrations in the three zones were assessed statistically.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 2, criterion 1. This dataset lists the newly-introduced species encountered on buoys and in epibenthic and Van Veen grab samples taken in the Belgian part of the North Sea (BPNS) between 2011 and 2016.