The national wastewater-based epidemiological surveillance of psychoactive substances monitors the presence of various psychoactive substances in several wastewater treatment plants across Belgium. This dataset contains the results per treatment plant since the beginning of the surveillance in 2025. The results consist of the psychoactive substances concentrations over time as well as other data needed for the interpretations such as the flow rates of the treatment plants and the population covered.

The data set includes three types of breakdown: Cities, Larger Urban zones or Functional Urban areas. BE_StatisticsBelgium_SH_SU_UA_CITY presents in the form of polygons the borders of the Belgian cities participating to the Urban Audit of the European Commission. Some cities consist in only one municipality (LAU2) while the others are the result of the aggregation of several municipalities (LAU2). Several versions of the breakdown (2001, 2002, 2010, 2019) follow one another because over the years new cities have taken part in it. The files can be linked to the statistical data collected for the Urban Audit. BE_StatisticsBelgium_SH_SU_UA_LUZ and BE_StatisticsBelgium_SH_SU_UA_FUA present in the form of polygons the areas of influence of the Urban Audit cities on the surrounding municipalities. The initial concept of Larger Urban Zones (LUZ) was replaced by the concept of Functional Urban areas (FUA) to take into account the movement of workers to the Urban Audit cities. LUZ / FUA are an aggregation of municipalities (LAU2). Several versions of the breakdown (2001, 2002, 2010, 2019) follow one another because over the years new LUZ / FUA have appeared or have seen their extension modified. The files can be linked to the statistical data collected for the Urban Audit.

The national wastewater-based epidemiological surveillance of influenza (commonly known as flu) monitors the influenza presence in several wastewater treatment plants across Belgium. This dataset contains the results per treatment plant since the beginning of the surveillance in January 2024. The results consist of the influenza concentrations over time as well as other data needed for the interpretations such as the flow rates of the treatment plants and the population covered.

The national wastewater-based epidemiological surveillance of SARS-CoV-2 monitors the SARS-CoV-2 presence in several wastewater treatment plants across Belgium. This dataset contains the results per treatment plant since the beginning of the surveillance in September 2020. The results consist of the SARS-CoV-2 concentrations over time as well as other data needed for the interpretations such as the flow rates of the treatment plants and the population covered.

The national wastewater-based epidemiological surveillance of respiratory syncytial virus (RSV) monitors the RSV presence in several wastewater treatment plants across Belgium. This dataset contains the results per treatment plant since the beginning of the surveillance in January 2024. The results consist of the RSV concentrations over time as well as other data needed for the interpretations such as the flow rates of the treatment plants and the population covered.

The data set contains a seamless polygonal layer representing the land cover in Belgium for the year 2012 and the year 2018. The polygons are spread over 32 classes from the CORINE Land Cover legend which are present un Belgium. The minimum map unit is 25 ha. The conceptual scale is 1:100 000. The data set also contains a polygon layer showing changes of more than 5 ha in the land cover between 2012 and 2018.

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) 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 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.

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.