In the Earth, the dynamo action is strongly linked to core freezing. There is a solid inner core, the growth of which provides a buoyancy flux that drives the dynamo. The buoyancy in this case derives from a difference in composition between the solid inner core and the fluid outer core. In planetary bodies smaller than the Earth, however, this core differentiation process may differ - Fe may precipitate at the core-mantle boundary (CMB) rather than in the center and may fall as iron snow and initially remelt with greater depth. A chemical stable sedimentation zone develops that comprises with time the entire core - at that time a solid inner core starts to grow. The dynamics of this system is not well understood and also whether it can generate a magnetic field or not. The Jovian moon Ganymede, which shows a present-day magnetic dipole field, is a candidate for which such a scenario has been suggested. We plan to study this Fe-snow regime with both a numerical and experimental approach. In the numerical study, we use a 2D/3D thermo-chemical convection model that considers crystallization and sinking of iron crystals together with the dynamics of the liquid core phase (for the 3D case the influence of the rotation of the Fe snow process is further studied).The numerical calculations will be complemented by two series of experiments: (1) investigations in metal alloys by means of X-ray radioscopy, and (2) measurements in transparent analogues by optical techniques. The experiments will examine typical features of the iron snow regime. On the one hand they will serve as a tool to validate the numerical approach and on the other hand they will yield important insight into sub-processes of the iron snow regime, which cannot be accessed within the numerical approach due to their complexity.
Background Society aims for a pollutant-free environment, reflected in initiatives under the European Green Deal, which seek to reduce hazardous substances and promote safe, sustainable chemical use. Comprehensive exposure data are needed to identify sources, understand mixtures and eliminate sources of chemical pollution. High-resolution mass spectrometry non-target screening (HRMS NTS) is increasingly used in environmental regulatory context to chemically characterise the environment as completely as possible and retrospectively screen for known and emerging substances. Results This study provides use cases for monitoring and chemicals management with data from the German NTSPortal, a database and visualisation tool for HRMS NTS data from surface water and suspended particulate matter of major German rivers. Its internal spectral library enables substance identification comparable to standardised target analysis, supporting regulatory acceptance of HRMS NTS data for prioritisation and mixture assessment. To demonstrate its potential to research and regulation, we characterised the spatial and temporal distribution of riverine chemical mixtures and present selected use cases relevant to EU environmental, emission, and chemical legislation. Despite pronounced spatial variability, mixture composition based on presence–absence data remained stable over time, with 855 of 1721 substances detected at least once and 247 occurring ubiquitously. Declining trends for regulated substances such as carbendazim and climbazole illustrate the effectiveness of regulatory measures. Overall, the results showed that NTS data repositories can help overcome fragmented exposure information and enable more consistent use of monitoring data across policy areas, including evaluation of the revised Urban Waste Water Treatment Directive and One Health concepts. Conclusions Data from the German NTSPortal enabled a multi-matrix and temporal characterisation of riverine chemical mixtures, revealing both stable mixture compositions over time and persistent, catchment-specific substances. These data facilitated high-resolution mixture assessments across space and time, alongside trend analyses that meet regulatory needs in environmental monitoring and chemical risk assessment. Further temporal, spatial, chemical and matrix-spanning expansion of HRMS NTS repositories will enhance their value for environmental monitoring programmes. Strengthening interoperability, implementing FAIR data principles, and developing advanced tools for prioritisation, quantification and toxicity prediction, including AI-based approaches, will be crucial to fully realise the regulatory potential of NTS portals in the future. © The Author(s) 2026.
Residence times is a key signature to characterize flow and transport at all temporal and spatial scales in different hydrological compartments. It is assumed that the spatial organisation of the landscape controls space-time organisation of the water cycle and related processes and hence the residence time. Combining flux and residence concentration data of natural tracers in water, stable isotopes, and artificial tracers will allow us to predict residence time and flow pathways in the different hydrological compartments as well as integrative for entire watersheds. We will investigate with different methods the fingerprint of hydrological processes found in the signal of isotopic composition and natural and artificial tracers of soil, ground and stream water in space and time. The temporal variability of isotopes in soil water, groundwater and stream water will be combined to benchmark transport and flow models and to derive a new functional form of short to long-term transit time distributions. The spatial patterns of stable isotopes in the saturated and unsaturated zone will be used to derive long-term flow pathways, mixing patterns and the proportion of evaporation to transpiration. Artificial tracer experiments using salt and electric resistivities will vizualize and quantify internal flow pathways in particular preferential flow pathways.
This dataset contains hydrochemical and soil data collected along the first 1.3 km downstream of the White Main spring in northern Bavaria, Germany, from March 2023 to November 2024. Stream water samples were analyzed for in situ parameters, including discharge, water temperature [°C], pH [-], redox potential [mV], and electrical conductivity [µS/cm], as well as laboratory-measured parameters, including major ions and trace metals [mmol/l], alkalinity [mmol/l], dissolved inorganic and organic carbon concentrations (DIC, DOC [mmol/l]), and their stable isotope ratios (δ13CDIC/DOC [‰ VPDB]). In addition, calculated partial pressure of CO2 (pCO2 [µatm]) and carbon dioxide fluxes (FCO2 [mmol m⁻² d⁻¹]) are provided for the stream water samples. The dataset also contains laboratory measurements related to soil-derived natural organic matter from acid and base extracts of soil samples, including zeta potential [mV], particle size distribution [%], ultraviolet-visible absorbance (UV-VIS), and fluorescence measurements. UV-VIS absorbance and fluorescence measurements were additionally performed on stream water samples. The datasets were collected to characterize hydrochemistry, carbon concentrations, carbon dioxide dynamics, and soil-derived organic matter properties in a granitic headwater stream and to provide a basis for reuse in studies of headwater biogeochemistry, carbon cycling, and soil-water interactions.
Tierhaltungsanlage In der Finkenstädt (Ursprungsplan) im Datenformat INSPIRE PLU Version 4.0.1
Water isotopes (δ²H and δ¹⁸O) were analyzed in samples from lakes and rivers in eastern Germany. This sub-dataset is derived from water samples collected from lake and river shores. Seasonal samples were collected in March, July, October 2022, and in March 2023, with a plastic syringe from 20-50 cm depth below water surface and directly filtered and transferred into a measurement vial. Stable isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. Measurement uncertainty was quantified to <0.5 ‰ for δ²H and <0.2 ‰ for δ¹⁸O. Water chemical parameters were determined in-situ with a portable WTW-multiparameter probe. The data give information about the seasonal isotope amplitude at the sampled spots and about spatial isotope variability in different branches of the associated river systems.
Water isotopes (δ2H and δ18O) were analyzed in samples collected in lakes associated to major riverine systems in northeastern Germany throughout 2020. This sub-dataset is derived from water samples collected from lake shores. Samples were taken in March and July 2020 with a pipette from 40-60 cm depth below water surface and directly transferred into a measurement vial. Stable isotope analysis was conducted at IGB Berlin, using a Picarro L2130-i cavity ring-down spectrometer. The data give information about the seasonal isotope amplitude in the sampled lakes and about spatial isotope variability in different branches of the associated riverine systems.
This dataset includes downcore measurements of dissolved inorganic carbon (DIC) and its stable carbon isotopic composition (δ13C-DIC), as well as solid-phase porosities and total organic carbon (TOC) contents from a sediment core retrieved using multi-corer sampling during RV Heincke expedition HE595 in 2022. The samples were collected in the framework of the Project APOC (Anthropogenic impacts on particulate organic carbon cycling in the North Sea). DIC contents were determined in the laboratories of the Alfred Wegener Institute (AWI) in Bremerhaven, Germany. The δ13C-DIC data were produced at MARUM—Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany. Solid-phase porosity data were produced in the laboratories of the Alfred Wegener Institute (AWI) in Bremerhaven, Germany. Total organic carbon contents were determined at the Faculty of Geosciences at the University of Bremen, Bremen, Germany.
This dataset contains dissolved inorganic/organic carbon (DIC/DOC) concentrations, its stable isotope ratios (δ13CDIC/DOC), partial pressure of carbon dioxide in the water column pCO₂(aq) (pCO2(aq)) and area-integrated CO₂ emission rates derived from flux calculations (FCO2; g C d⁻¹), along with corresponding parameters (temperature, pH, calcium, bicarbonate) collected from the Danube River and its key tributaries during five seasonal sampling campaigns in 2023 and 2024. Water samples were collected using a weighted 2 L sampling bottle submerged 1–2 meters below the surface, with sampling conducted from the river center via bridges or passenger boats, and occasionally from the riverbank. In situ temperature measurements were taken with a multiparameter instrument (HQ40d, HACH™, Loveland, CO, USA). δ13ODIC/DOC was analyzed using a OI Analytical Aurora 1030W-IRMS. This dataset is providing valuable insights into carbon dynamics in a large river system and support investigations of biogeochemical cycling. It further can inform ecosystem management and conservation strategies under changing environmental conditions.
Anlagen nach dem Bundes-Immissionsschutzgesetz im Landkreis Verden
| Organisation | Count |
|---|---|
| Bund | 492 |
| Europa | 13 |
| Global | 1 |
| Kommune | 87 |
| Land | 364 |
| Weitere | 62 |
| Wissenschaft | 453 |
| Zivilgesellschaft | 10 |
| Type | Count |
|---|---|
| Agrarwirtschaft | 1 |
| Chemische Verbindung | 4 |
| Daten und Messstellen | 224 |
| Ereignis | 2 |
| Förderprogramm | 418 |
| Hochwertiger Datensatz | 1 |
| Software | 1 |
| Taxon | 33 |
| Text | 150 |
| Umweltprüfung | 168 |
| unbekannt | 209 |
| License | Count |
|---|---|
| Geschlossen | 305 |
| Offen | 837 |
| Unbekannt | 25 |
| Language | Count |
|---|---|
| Deutsch | 514 |
| Englisch | 693 |
| Resource type | Count |
|---|---|
| Archiv | 127 |
| Bild | 7 |
| Datei | 157 |
| Dokument | 172 |
| Keine | 507 |
| Unbekannt | 3 |
| Webdienst | 28 |
| Webseite | 245 |
| Topic | Count |
|---|---|
| Boden | 736 |
| Lebewesen und Lebensräume | 932 |
| Luft | 580 |
| Mensch und Umwelt | 1167 |
| Wasser | 717 |
| Weitere | 1077 |