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.

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) 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).

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 11, criterion 1. This dataset describes the impulsive noise generated during percussion pile emplacement for offshore wind farm construction and unexploded ordnance (UxO) explosions. Impulsive underwater sound (pressure) was measured during pile driving operations in Belgian waters, for different types of foundations (monopiles of different diameters, foundations of ducts with a smaller diameter) and hydraulic hammers with different energy powers. The results of measurements at Bligh Bank and Thornton Bank, with a resulting extrapolation of zero to peak noise level (Lz-p) at 750m and Sound Exposure Level (SEL) (no mitigation measures deployed), are presented (Norro et al., 2013).

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 8, criterion 1. This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 8, criterion 1. This dataset contains the concentrations of priority substances (tributyltin, polycyclic aromatic hydrocarbons (PAHs) and polybrominated diphenylethers (PBDEs)) measured in the water column at three stations in the Belgian part of the North Sea between 2009 and 2014 (as reported in the frame of the WFD in 2016). In total, 45 different parameters are measured.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 8, criterion 1. This dataset contains the contaminant concentrations measured in sediments at 10 monitoring stations in the Belgian part of the North Sea between 2011 and 2015. 88 parameters are measured in the upper part of the sea bottom by a Van Veen grab sampler. The contaminants are analyzed on the fraction < 63 µm. PCBs and heavy metals are analyzed by ILVO (and CODA). PBDEs, PAHs and organotin compounds are analysed by KBIN-OD Nature, PAHs and organotin based on an accredited method (ISO/IEC 17025).

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 1, criterion 1. Stranded porpoises often show traces of incidental catch in fishing nets (bycatch), a major cause of death for this cetacean in the North Sea. Based on the number of stranded animals showing traces of bycatch, it can be estimated that up to a few dozen porpoises are caught per year. For extrapolation of bycatch data to effects at population level, reference is made to (future) initiatives at regional level.

This dataset is part of the 2018 Belgian submission for the Marine Strategy Framework Directive (MSFD) linked to descriptor 6, criterion 2. This dataset describes and maps the physical disturbance to the seabed in the Belgian part of the North Sea (BPNS) between 2011 and 2016. The dataset combines different layers of human activities leading to a disturbance of the seabed, including power cables with its rock dump, dredging and dumping, extraction, war ammunition stocking and wind farms. The area disturbed is mapped and quantified per year, per activity and per benthic broad habitat.

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.