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Korrosionsempfindliche Dosimetermaterialien zur Überwachung der Umweltbedingungen an Kulturgütern

Die einzelnen Belastungsfaktoren von Kulturgütern können durch apparativ aufwendige und kostenintensive Einzelmessungen mit Hilfe der modernen Analytik genau bestimmt werden. Mit den sogenannten Glassensoren wurde am Fraunhofer-Institut für Silicatforschung (ISC) eine elegante und zerstörungsfreie Methode entwickelt, die ohne aufwendige Messungen der einzelnen Parameter die auftretenden Gesamtbelastungen über einen längeren Zeitraum hinweg registrieren kann. Die Verwendung von sensibilisierten Glasflächen als Dosimetermaterial wurde für den bisherigen Anwendungsbereich ausgeschöpft. Ziel dieses Vorhabens ist es, neue korrosionsempfindliche Materialien und Komponenten herzustellen und für den prinzipiellen Einsatz zur Überwachung der Umweltbedingungen an Kulturgütern zu prüfen. Zum einen sollen Granulate der bisherigen Glasmaterialien mit unterschiedlicher Körnung in eine NIR-transparente Trägermatrix aus SiO2-Aerogel eingebracht werden. Zum anderen bietet sich die Modifizierung der inneren Oberfläche von SiO2-Aerogelen an, die dann selbst als detektionsaktive Medien fungieren können. Ein weiterer Syntheseweg soll so gewählt werden, dass Aerogel- oder Xerogelschichten ohne überkritische Trocknung auf Glas als Trägermaterial hergestellt werden. In jedem Fall muss der korrosive Einfluss bestimmter Umweltfaktoren (Feuchte, Temperatur, Schadgase) in einem Expositionsprogramm in Klimakammern, zunächst durch Variation einzelner Parameter und schließlich durch deren Kombination systematisch charakterisiert werden. Nach Abschluss dieser Labortestphase können - bei Projektende - Expositionsprogramme in Museen verwirklicht werden.

Seismological experiment at Strokkur from 2020

Seismological experiment at Strokkur from 2020" is a seismological experiment realized at the most active geyser on Iceland by Eva Eibl (University of Potsdam) in collaboration with Gylfi P. Hersir formerly at ISOR Iceland. The geyser is part of the Haukadalur geothermal area in south Iceland, which contains numerous geothermal anomalies, hot springs, and basins (Walter et al., 2018). Strokkur is a pool geyser and has a silica sinter edifice with a water basin on top, which is about 12m in diameter with a central tube of more than 20m depth. The aim of the seismic experiment is to monitor eruptions of Strokkur geyser from March 2020 using three broadband seismic stations (Nanometrics Trillium Compact 120s). Sensors were buried at distances of 38.8m (GE4, SE), 47.3m (GE3, SW), and 42.5m (GE2, N) from Strokkur center. Within this time period about 1 month of data is missing due to power outages. At any other times at least one station recorded the eruptions. From this dataset, converted to MSEED using Pyrocko, currently a catalogue of 506,131 water fountains was determined and further investigated in Eibl et al. (2025). In addition, Eibl et al. (2025) assessed the effect of the weather on the system including the bubble trap suspected at around 24 m depth by Eibl et al. (2021). Waveform data are available from the GEOFON data centre, under network code 2Z.

KOSMOS 2023 Helgoland mesocosm study on ocean alkalinity enhancement: dissolved inorganic nutrients, chlorophyll a and suspended particulate organic matter

We conducted a mesocosm study to investigate ecosystem responses to ocean alkalinity enhancement (OAE) in the temperate waters of the German North Sea on Helgoland in spring 2023. We simulated non-CO2-equilibrated OAE via calcium hydroxide through the addition of calcium chloride and sodium hydroxide. Twelve 6 m³ mesocosms were used to simulate two scenarios: in six mesocosms we established a gradient of added alkalinity from 0 to 1250 µmol/kg in increments of 250 µmol/kg, simulating immediate (imm) dilution of alkalised waters. For the second set of six mesocosms, alkalinity was added only to the top 1 m of each mesocosm, doubling the target added alkalinity. The top layer was mixed with the untreated bottom layer after 48 hours, simulating delayed dilution of alkalised waters (del) and ultimately leading to the same alkalinity gradient as the immediate dilution treatment. This data contains water column biogeochemical variables, including dissolved inorganic nutrient concentrations (µmol/L), chlorophyll a concentrations (µg/L) and suspended particulate matter (biogenic silica, particulate organic carbon, nitrogen and phosphate; µmol/L). Nutrients, particulate organic phosphate and biogenic silica were measured spectrophotometrically (Unicam UV 300, Thermo Spectronic, USA). High-performance liquid chromatography (Thermo Scientific HPLC Ultimate 3000) was performed for chlorophyll a determination and particulate organic carbon and nitrogen were measured using an elemental analyser (Flash EA, Thermo Fisher).

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Investigation of mechanism driving glacial/interglacial variability in stratification/mixing and biological productivity of the Pacific Southern Ocean and potential implications on air-sea CO2-exchange: synthesis of climate and ocean biogeochemical modeling with paleoceanographic reconstructions

Atmospheric CO2 concentrations present a repetitive pattern of gradual decline and rapid increase during the last climate cycles, closely related to temperature and sea level change. During the Last Glacial Maximum (LGM; 23-19 kyr BP), when sea level was ca. 120 m below present, the ocean must have stored additionally about 750 Gt carbon. There is consensus that the Southern Ocean represents a key area governing past and present CO2 change. The latter is not only of high scientific but also of socio-economic and political concern since the Southern Ocean provides the potential for an efficient sink of anthropogenic carbon. However, the sensitivity of this carbon sink to climate-change induced reorganizations in wind patterns, ocean circulation, stratification, sea ice extent and biological production remains under debate. Models were not yet able to reproduce the necessary mechanisms involved, potentially due to a lack of the dynamic representation/resolution of atmospheric and oceanic circulation as well as missing carbon cycling. Data on past Southern Ocean hydrography and productivity are mainly from the Atlantic sector, thus do not adequately document conditions in the Pacific sector. This sector is not only the largest part of the Southern Ocean, but it also represents the main drainage area of the marine-based West Antarctic Ice Sheet (WAIS). In the proposed study we aim to generate paleo-data sets with a newly established proxy method from sediment core transects across the Pacific Southern Ocean. This will enhance the baselines for the understanding and modeling of the Southern Ocean's role in carbon cyling, i.e. ocean/atmosphere CO2 exchange and carbon sequestration. It will also allow insight into the response of the WAIS to past warmer than present conditions. Paired isotope measurements (oxygen, silicon) will be made on purified diatoms and radiolarians to describe glacial/interglacial contrasts in physical and nutrient properties at surface and subsurface water depth. This will be used to test (i) the impact of yet unconsidered dust-borne micronutrient deposition on the glacial South Pacific on shifts of primary productivity, Si-uptake rates and carbon export, (ii) the 'silicic-acid leakage' hypothesis (SALH) and (iii) the formation and extent of surface water stratification. Diatom and radiolarian oxygen isotopes will provide information on the timing of surface ocean salinity anomalies resulting from WAIS melt water. Climate model simulations using a complex coupled atmosphere ocean general circulation model (AOGCM) in combination with a sophisticated ocean biogeochemical model including Si-isotopes will be used for comparison with the paleo records. The analysis will cover spatial as well as temporal variability patterns of Southern Ocean hydrography, nutrient cycling and air-sea CO2-exchange. With the help of the climate model we aim to better separate and statistically analyse the individual impacts of ocean circulation and bio

Chemical composition and Sr, Nd, Pb isotope ratios of mafic igneous rocks from the Ordovician Saxothuringian basin east of and within the post-Devonian Müncheberg massif, NE Bavaria, Germany

The sampling area is located east (E-domain) and west (W-domain) of the Münchberg gneiss massif, NE Bavaria. Germany. Major and trace element compositions and Sr, Nd, and Pb isotope composition of a selected subset of Ordovician samples and post- Devonian samples of mafic igneous rocks are documented in the Table 1 'E-domain'. Sr, Nd, and Pb isotope composition of selected mafic igneous rocks from the W-domain of Ordovicician, Silurian, and Devonian age are documented together with the previously analysed Rb-Sr, Sm-Nd, U-Th-Pb concentrations (Höhn et. al., 2018, doi:10.1007/s00531-017-1497-2) in the Table 2 'W-domain'.

Elementkarte der Digitalen Lithogeochemischen Karte von Bayern 1:25.000 (dLGK25) - Siliziumdioxid (P90)

Die Elementkarte stellt die räumliche Verteilung der klassifizierten Gehalte des 90. Perzentils von Siliziumdioxid (in Gew.-%) innerhalb der 184 geochemischen Gesteinseinheiten in Bayern dar. In die Auswertung gehen dabei nur die Daten der ersten (von maximal drei) Lithologien einer geochemischen Gesteinseinheit ein. Für Informationen im Hinblick auf die Auswertung der Daten sowie auf die kartenmäßige Darstellung wird auf die Metadaten der digitalen Lithogeochemischen Karte 1:25 000 von Bayern (dLGK25) verwiesen.

Elementkarte der Digitalen Lithogeochemischen Karte von Bayern 1:25.000 (dLGK25) - Siliziumdioxid (P50)

Die Elementkarte stellt die räumliche Verteilung der klassifizierten Gehalte des 50. Perzentils von Siliziumdioxid (in Gew.-%) innerhalb der 184 geochemischen Gesteinseinheiten in Bayern dar. In die Auswertung gehen dabei nur die Daten der ersten (von maximal drei) Lithologien einer geochemischen Gesteinseinheit ein. Für Informationen im Hinblick auf die Auswertung der Daten sowie auf die kartenmäßige Darstellung wird auf die Metadaten der digitalen Lithogeochemischen Karte 1:25 000 von Bayern (dLGK25) verwiesen.

Pore-water pH, H2S, Cl-, SO42-, SiO2, NO2-, PO43-, NH4+, NO3-, major and trace element data from MUC cores taken during RV HEINCKE cruises HE575 and HE595 in the Helgoland Mud Area, German Bight

This dataset includes downcore measurements of pH values, H2S, Cl-, SO42-, SiO2, NO2-, PO43-, NH4+, NO3-, As, Ba, Ca, Cu, Fe, K, Li, Mg, Mn, Mo, P, Si and Sr concentrations for sediment cores retrieved using multi-corer sampling during RV Heincke expeditions HE575 and HE595 in 2021 and 2022, respectively. The samples were collected in the framework of the Project APOC (Anthropogenic impacts on particulate organic carbon cycling in the North Sea). All measurements were performed in the laboratories of the Alfred Wegener Institute (AWI) in Bremerhaven, Germany, except pH values, which were determined onboard the research vessel.

KOSMOS 2023 Helgoland mesocosm study on ocean alkalinity enhancement: sediment trap particle flux data and water column biogeochemistry

The data presented herein originates from a mesocosm study conducted as part of the BMBF CDRmare, Retake project (grant agreement no. 03F0895A), aimed at investigating the ecological ramifications of ocean alkalinity enhancement (OAE). Twelve mesocosms were deployed in Helgoland South Harbor, Germany, and systematically sampled using integrated water samplers over the period spanning from March 12th to April 20th, 2023. Six alkalinity levels under two dilution scenarios were established to differentiate between localized and uniform OAE additions. Alkalinity was increased stepwise to ΔTAmax = 1250 μmol kg-1 (250 μmol TA kg-1 increments) using sodium hydroxide (NaOH) with calcium chloride (CaCl2) to simulate cation release during calcium-based mineral dissolution, causing strong carbonate chemistry perturbations (e.g., pHT > 9.25). The dataset encompasses a spectrum of sediment trap particle flux data, water column biogeochemistry including pigment variables, inorganic nutrients, carbonate chemistry parameters. The study and data set offer insights into impacts of alkalinity enhancement on marine ecosystems and their associated biogeochemistry.

LGRB-BW HW_HYD: Siliziumdioxid

Die vorliegende Auswertung zeigt für Baden-Württemberg die geogenen Hintergrundkonzentrationen einer Vielzahl von Grundwasserinhaltsstoffen in Abhängigkeit von den durchflossenen Gesteinen. Sie liefert damit die Grundlage für die Definition von Warnwerten, Grenzwerten und Sanierungszielen in Regelwerken, in der Gesetzgebung und für die Praxis. Die Auswertung basiert auf Proben von oberflächennahen Grundwasseraufschlüssen mit extensiv genutzten, überwiegend bewaldeten oder als Weideland bewirtschafteten Einzugsgebieten. Die Methodik sowie die Ergebnisse der Auswertung sind in den LGRB-Informationen 23 (https://produkte.lgrb-bw.de/docPool/c621_data.pdf) ausführlich beschrieben.

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