Over the past 30 years, the significant increasing exploitation of Rare Earth Elements (REEs) for their use in new technologies (e.g. low-carbon energy, multimedia, medicine) has led to their release into the environment. The occurrence of these emerging contaminants in the environment leads to major health and environmental issues. In the last decade, a growing number of studies have observed the presence of anthropogenic REEs in freshwater and marine aquatic organisms. However, limited information is currently available regarding the natural levels of REE concentrations in aquatic organisms. A global understanding of these natural levels is therefore essential to: i) understand the natural biogeochemical cycles of REEs; ii) gain better insights into the risks of exposure associated with anthropogenic REEs; and iii) determine research perspectives by evaluating current knowledge gaps.
This dataset compiles concentrations for the 14 stable REEs, from lanthanum (La) to lutetium (Lu), and sum of REE concentrations (∑REE). These data were compiled from 102 articles published over the last 50 years, between April 1973 and January 2023. These articles provided at least one concentration value for one REE in one aquatic organism, regardless of the analyzed tissue (e.g. whole organism, leaf, liver, shell). A total of 15,710 concentration data were compiled for aquatic organisms. The REE concentrations were compiled for in situ aquatic organisms (expressed in µg.kg-1). The available concentration data for water (n=2105; in µg.l-1) and sediment samples (n=1125; in µg.kg-1) from these studies were also compiled. These field data span across a global scale, encompassing both freshwater and marine ecosystems.
The REE concentrations were associated with various biological parameters (e.g. Phylum, Species, Habitat, Tissues) and spatial parameters (e.g. Ecosystem, Area). For each of these parameters, the most precise information was obtained from the published articles providing these data. Additionally, the data were classified based on the presence or absence of environmental REE contamination at the sampling site. Further complementary information is available in the dataset (ReadMe tab). The reference for each of the cited articles is also provided in the dataset (References tab).
The Long-Term Ecological Research observatory HAUSGARTEN was established by the Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung in the Fram Strait in summer 1999 to detect and track the impact of large-scale environmental changes on the marine ecosystem in the transition zone between the northern North Atlantic and the central Arctic Ocean. In this area, bathymetric data have been recorded with multibeam echosounders during 44 research expeditions on RV Polarstern and RV Maria S. Merian since 1984. From these data, a digital elevation model was generated and geostatistical analyses were performed to calculate geospatial derivatives and quantitative terrain descriptors for subsequent terrain analyses and habitat mapping. The dataset covers an area from 78°N to 81°N and 6°W to 12°E.
To create the data product, archive data was used from seven different multibeam echosounders in various raw data formats. This data has been processed and cleaned with CARIS HIPS & SIPS, including sound velocity correction for datasets from 1999 and newer. Older datasets are calculated with a static sound velocity of 1500 m/s. Soundings where exported for gridding with Generic Mapping Tools (GMT) nearneighbor. The resulting Digital Elevation Model (DEM) is in the WGS84/Arctic Polar Stereographic (EPSG:3995) projection with a cell size of 100m x 100m. The hillshade was computed with a combination of slope and synthetic illumination with a vertical exaggeration of 10. Slope inclination was calculated with GDAL tool Slope with the formula of Zevenbergen and Thorne (1987) in degree. Terrain Ruggedness Index (TRI) was computed with the QGIS tool Ruggedness index following the approach of Riley et al. (1999) in meters. For the Bathymetric Position Indices (BPI), focal statistics have been calculated with the GRASS tool "r.neighbors" and the QGIS raster calculator following the concept of the Topographic Position Index (Weiss, 2001) with a circular reference area of 99 cells (broad) and 9 cells (fine).
The additional coverage polygon layer gives and overview on the used datasets and their corresponding metadata. The map gives an overview on the LTER HAUSGARTEN area and the HAUSGARTEN 2024 DEM.
Oxygen isotopes in biogenic silica (δ18O BSi) from lake sediments allow for quantitative reconstruction of past hydroclimate and proxy–model comparison in terrestrial environments. The signals of individual records have been attributed to different factors, such as air temperature (T air ), atmospheric circulation patterns, hydrological changes and lake evaporation. Here, we provide 55 composite down–core records published to date and complemented with additional lake basin parameters (e.g. lake water residence time and catchment size) to best characterize the signal properties. Records feature widely different temporal coverage and resolution ranging from decadal–scale records covering the last 150 years to records with multi–millennial scale resolution spanning glacial–interglacial cycles. Best coverage in number of records (N=37) and datapoints (N=2112) is available for northern hemispheric (NH) extra–tropic regions throughout the Holocene (corresponding to Marine Isotope Stage 1; MIS 1).