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Carbonate chemistry parameters calculated from measured pH, total alkalinity, salinity and temperature in the alkalization mesocosms of a chronic Ostrea edulis alkalinity-enhancement exposure experiment

This dataset contains calculated carbonate chemistry parameters, including the concentrations of dissolved CO2, HCO3-, CO32- and dissolved inorganic carbon, the fugacity and partial pressure of CO2 and the saturation states of aragonite (Ωarag) and calcite (Ωcalc), for the alkalization mesocosms. Values were calculated from pH, total alkalinity, salinity and temperature measured between 17 April and 19 June 2024, using the seacarb package (Orr et al., 2018) in R (V. 4.3.2). Measured pH values, which refer to the NBS scale, were first converted to the total scale using the total proton activity coefficient fH of Takahashi et al. (1982), lowering pH by 0.12 to 0.13 units across the measured salinity and temperature range. Calculations used the carbonic acid dissociation constants of Lueker et al. (2000), the bisulfate dissociation constant of Dickson (1990), the hydrogen fluoride constant of Perez & Fraga (1987), total boron after Uppström (1974) and the aragonite and calcite solubility products of Mucci (1983), all evaluated at in situ temperature and salinity. The conversion from the NBS to the total scale carries a residual uncertainty of about 0.01 to 0.02 pH units, because the liquid junction potential between the dilute calibration buffers and seawater is not fully captured by fH. This propagates to an uncertainty of roughly 5 to 15 % in calculated pCO2 and a correspondingly smaller uncertainty in the saturation states.

Rückstandsgehalte und Verteilung von subtherapeutischen Antibiotika in Feedlot-Böden

Feedlots sind v.a. in Nordamerika verbreitete Tierproduktionsbetriebe mit intensivster Freilandhaltung. Es wird vermutet, dass Feedlots Brennpunkte einer Umweltbelastung mit pharmazeutischen Antibiotika sind, da große Tierbestände gehalten werden, die regelmäßig Antibiotika erhalten. Es wurden Bodenproben von einer Grasland-Kontrolle sowie Boden- und Tierdung-Proben von Bodenprofilen eines gewerblichen und eines experimentellen Feedlots entnommen und analysiert. Rückstände der üblicherweise verwendeten Antibiotika Sulfamethazin, Chlortetracyclin und Tylosin wurden mit unterschiedlichen Konzentrationen in Dung, Boden und Wasser gefunden. Die Ergebnisse weisen auf eine nicht unerhebliche Persistenz, Tiefenverlagerung und insbesondere Oberflächenabfluss der Antibiotika Sulfamethazin und Chlortetracyclin hin.

German Eco-Cycle and Waste Policies: The Current State of German Mandatory Deposit System and End-of-life-Vehicles (Automotive Shredder Residue - ASR)

Continuous hyperspectral above-water radiometric data along RV HEINCKE cruise HE681

This data set was recorded by permanently installed above-water radiometry onboard RV HEINCKE. Five TriOS instruments are installed at the top of the foremast: one irradiance sensor (ACC) to measure the incoming solar irradiance as a reference, 2 radiometers (ARC) to measure the incoming sky radiance, 2 radiometers (ARC) to measure the sea-surface leaving radiance. One set of radiometers is pointed to 45° starboard and the other to 45° port. The data were recorded with the MSDA-XE software in 15s interval and transferred via cloud. The data were then reformatted and processed with the community processor HyperCP. Ancillary data was taken from the mastertrack and Insightics DSHIP extraction. Data were processed for coastal conditions using sky/sunglint correction by Zhang et al. (2017), NIR residual correction using Ruddick et al. 2006, and BRDF correction based on IOP-based approach by Lee.

Carbonate chemistry parameters calculated from measured pH, total alkalinity, salinity and temperature in the exposure mesocosms of a chronic Ostrea edulis alkalinity-enhancement exposure experiment

This dataset contains calculated carbonate chemistry parameters, including the concentrations of dissolved CO2, HCO3-, CO32- and dissolved inorganic carbon, the fugacity and partial pressure of CO2 and the saturation states of aragonite (Ωarag) and calcite (Ωcalc), for the exposure mesocosms. Values were calculated from pH, total alkalinity, salinity and temperature measured between 8 May and 10 July 2024, using the seacarb package (Orr et al., 2018) in R (V. 4.3.2). Measured pH values, which refer to the NBS scale, were first converted to the total scale using the total proton activity coefficient fH of Takahashi et al. (1982), lowering pH by 0.12 to 0.13 units across the measured salinity and temperature range. Calculations used the carbonic acid dissociation constants of Lueker et al. (2000), the bisulfate dissociation constant of Dickson (1990), the hydrogen fluoride constant of Perez & Fraga (1987), total boron after Uppström (1974) and the aragonite and calcite solubility products of Mucci (1983), all evaluated at in situ temperature and salinity. The conversion from the NBS to the total scale carries a residual uncertainty of about 0.01 to 0.02 pH units, because the liquid junction potential between the dilute calibration buffers and seawater is not fully captured by fH. This propagates to an uncertainty of roughly 5 to 15 % in calculated pCO2 and a correspondingly smaller uncertainty in the saturation states.

Electron diffraction patterns and HR-EBSD data from laboratory deformed olivine aggregates

This dataset is supplemental to the paper Wiesman et al. (submitted) and contains data on the density of dislocations and their stress fields in olivine rocks deformed via laboratory experiments. The data were used to investigate how the quality of diffraction patterns obtained via electron backscatter diffraction (EBSD) affect the stress maps and geometrically necessary dislocation (GND) maps obtained via analysis with high-angular resolution electron backscatter diffraction (HR-EBSD). These results can be used to optimize the patterns collected during EBSD to reduce noise in the HR-EBSD analysis. Data are provided in a zip folder and include: • Measurements of lattice orientation via EBSD: six raw .ctf files and six processed .ctf files of regions mapped with HR-EBSD • Examples of electron backscatter diffraction patterns used to calculate radial power spectra: 12 .tiff files of diffraction patterns • Densities of geometrically necessary dislocations from the HR-EBSD analysis: six .txt files of processed data • Residual stress heterogeneity also determined from HR-EBSD analysis: six .txt files of processed data Data types and the number of frames averaged are also indicated in the file names. Files are organized into folders by the number of frames averaged. A full description is available in the data description file.

GC-MS-Analyse zur Unterstuetzung der Charakterisierung und Reinigung kontaminierter Waesser und Schlaemme

In der Bundesrepublik Deutschland, insbesondere im Umfeld Thueringens gibt es eine Vielzahl von Altlasten, die mit den verschiedenen Verfahren der Bodenreinigung saniert werden koennen. Bei kostenguenstigen Verfahren, wie z.B. der Bodenwaesche, bleiben bestimmte Schadstoffraktionen als hochbelastete Waesser und Schlaemme zurueck. Soweit es bei dem derzeitigen Stand der Technik wirtschaftlich moeglich ist, koennen sie weiter aufbereitet werden. Hier kommen verschiedene Verfahren, u.a. Einsatz von Aktivkohle, Hochleistungsbiologie, Strippen, und die chemische Oxidation zum Einsatz. Zur Entwicklung weiterer Verfahren zu diesem Zweck ist es erforderlich, begleitende Untersuchungen der einzelnen Verfahrensschritte zu taetigen, um somit zur Verfahrensoptimierung beizutragen und neuartigen Verfahren den Weg zur Einsatzfaehigkeit zu ebnen. Das Forschungsprojekt soll das Profil der Fachhochschule Erfurt in der Umweltanalytik erweitern sowie Gelegenheit geben, ein ueber den Durchschnitt hinausreichendes Fachwissen zu etablieren. Es soll insbesondere dem Fachbereich Versorgungstechnik, der den Aufbaustudiengang Umwelttechnik mit beinhaltet, ermoeglichen, Wirtschaftsunternehmen vor allem in Thueringen Kooperationsmoeglichkeiten anzubieten, die diese fuer die Entwicklung geeigneter Erzeugnisse, Verfahren und Anlagen nutzen koennen, um somit ihre Wettbewerbsfaehigkeit zu steigern.

Release of hexavalent chromium from ore processing residues and the potential of biochar for chromium immobilization in polluted soils

Chromium (Cr) is introduced into the environment by several anthropogenic activities. A striking ex-ample is the area around Kanpur in the Indian state of Uttar Pradesh, where large amounts of Cr-containing wastes have been recently illegally deposited. Hexavalent Cr, a highly toxic and mobile contaminant, is present in significant amounts in these wastes, severely affecting the quality of sur-roundings soils, sediments, and ground waters. The first major goal of this study is to clarify the solid phase speciation of Cr in these wastes and to examine its leaching behavior. X-ray diffraction and synchrotron-based X-ray absorption spectroscopy techniques will be employed for quantitative solid phase speciation of Cr. Its leaching behavior will be studied in column experiments performed at un-saturated moisture conditions with flow interruptions simulating monsoon rain events. Combined with geochemical modeling, the results will allow the evaluation of the leaching potential and release kinetics of Cr from the waste materials. The second major goal is to investigate the spatial distribution, speciation, and solubility of Cr in the rooting zone of chromate-contaminated soils surrounding the landfills, and to study the suitability of biochar as novel soil amendment for mitigating the deleterious effects of chromate pollution. Detailed field samplings and laboratory soil incubation studies will be carried out with two agricultural soils and biochar from the Kanpur region.

Menge, Zusammensetzung und Umsetzung der organischen Substanz im Unterboden

Das Wissen über die Menge, Zusammensetzung und Umsetzung der organischen Substanz in Böden der gemäßigten Breiten beschränkt sich bis auf wenige Ausnahmen auf die Oberböden (A-Horizonte und Auflagen). Hier finden sich die höchsten Konzentrationen der organischen Substanz. Jüngere Inventurarbeiten haben nun gezeigt, dass auch im Unterboden (B- und Cv-Horizonte) beträchtliche Mengen an organischer Substanz, allerdings in niedrigen Konzentrationen vorliegen. Ziel des geplanten Vorhabens ist es, (1) die Menge der organischen Substanz im Unterboden zu erfassen, (2) ihre Zusammensetzung und Herkunft zu bestimmen und (3) ihre Umsetzbarkeit zu erfassen. Daraus sollen Rückschlüsse auf die Stabilisierungsmechanismen der organischen Substanz im Unterboden gezogen werden. Nach einer Inventur der Bodenprofile an den SPP-Standorten (C-Gehalte, 14C-Alter) erfolgt die Erfassung der Zusammensetzung der organischen Substanz mittels Festkörper-13C-NMR-Spektroskopie. Die Zusammensetzung der Lipid-, Polysaccharid- und Ligninfraktion soll Hinweise auf die Herkunft der stabilisierten organischen Substanz differenziert nach oberirdischen, unterirdischen Pflanzenrückständen und mikrobiellen Resten geben. Abbauversuche unter kontrollierten Bedingungen im Labor und die Erfassung des 14C-Alters des freigesetzten CO2 sollen Aufschluß über die Umsetzbarkeit des 'jungen' und 'alten' C im Unterboden geben. Dabei werden jeweils die Profile über die gesamte Entwicklungstiefe betrachtet, um die Unterbodenhorizonte in Bezug zu den Oberböden und zu den Ergebnissen anderer AG im SPP zu setzen. Darauf aufbauend können dann in den nächsten Phasen des SPP die Eigenschaften der organischen Substanz im Unterboden und die Regulation der C-Umsetzungen im Unterboden untersucht werden.

Quantification of small-scale physicochemical properties of intact macropore surfaces in structured soils

In structured soils, the interaction of percolating water and reactive solutes with the soil matrix is mostly restricted to the surfaces of preferential flow paths. Flow paths, i.e., macropores, are formed by worm burrows, decayed root channels, cracks, and inter-aggregate spaces. While biopores are covered by earthworm casts and mucilage or by root residues, aggregates and cracks are often coated by soil organic matter (SOM), oxides, and clay minerals especially in the clay illuviation horizons of Luvisols. The SOM as well as the clay mineral composition and concentration strongly determine the wettability and sorption capacity of the coatings and thus control water and solute movement as well as the mass exchange between the preferential flow paths and the soil matrix. The objective of this proposal is the quantitative description of the small-scale distribution of physicochemical properties of intact structural surfaces and flow path surfaces and of their distribution in the soil volume. Samples of Bt horizons of Luvisols from Loess will be compared with those from glacial till. At intact structural surfaces prepared from soil clods, the spatial distribution (mm-scale) of SOM and clay mineral composition will be characterized with DRIFT (Diffuse reflectance infrared Fourier transform) spectroscopy using a self-developed mapping technique. For samples manually separated from coated surfaces and biopore walls, the contents of organic carbon (Corg) and the cation exchange capacity (CEC) will be analyzed and related to the intensities of specific signals in DRIFT spectra using Partial Least Square Regression (PLSR) analysis. The signal intensities of the DRIFT mapping spectra will be used to quantify the spatial distribution of Corg and CEC at these structural surfaces. The DRIFT mapping data will also be used for qualitatively characterizing the small scale distribution of the recalcitrance, humification, and microbial activity of the SOM from structural surfaces. The clay mineral composition of defined surface regions will be characterized by combining DRIFT spectroscopic with X-ray diffractometric analysis of manually separated samples. Subsequently, the spatial distribution of the clay mineral composition at structural surfaces will be determined from the intensities of clay mineral-specific signals in the DRIFT mapping spectra and exemplarily compared to scanning electron microscopic and infrared microscopic analysis of thin sections and thin polished micro-sections. The three-dimensional spatial distribution of the total structural surfaces in the volume of the Bt horizons will be quantified using X-ray computed tomography (CT) analysis of soil cores. The active preferential flow paths will be visualized and quantified by field tracer experiments. These CT and tracer data will be used to transfer the properties of the structural surfaces characterized by DRIFT mapping onto the active preferential flow paths in the Bt horizons.

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