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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.

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.

Untersuchung der Bildung und der Struktur gebundener Rückstände des Fungizids Cyprodinil in Pflanzen

Ziel des Projektes ist es, die gebundenen Rückstände des Fungizids Cyprodinil, die in Weizenstroh bis zu 45 Prozent und in Körnern bis zu 30 Prozent des applizierten Wirkstoffs betragen können, bezüglich ihrer Struktur und der Art der Bindung zu charakterisieren. Die in den unlöslichen Pflanzenfraktionen festgelegten Rückstände sollen durch klassische Aufschlüsse und, als zu entwickelnde neue Methode, durch Silylierung freigesetzt, in organische Lösungsmittel überführt und mit hochauflösender NMR-Spektroskopie sowie mit chromatographischen Methoden untersucht werden. Weiterhin sind Festkörper-NMR-Untersuchungen der Rückstände in festen Pflanzenproben und -fraktionen vorgesehen. Cyprodinil wird für die geplanten NMR-Untersuchungen vom Hersteller, Novartis, an geeigneten Molekülpositionen mit 13C markiert. Für die Lokalisation und quantitative Erfassung der Rückstände wird zusätzlich 14C-markierter Wirkstoff eingesetzt. Um größere Mengen von Metaboliten und gebundenen Rückständen für die geplanten Charakterisierungen herzustellen, soll Cyprodinil auch in Weizen-Zellkulturen inkubiert werden. Zur Verminderung der NMR-Untergrundsignale der Pflanzenmatrix ist vorgesehen, die Inkubation in Pflanzen bzw. Zellkulturen durchzuführen, deren natürlicher 13C-Gehalt abgereichert wurde. Für spektroskopische Vergleichsmessungen ist die Kopplung des Fungizids an synthetische Ligninpolymere geplant.

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.

Kombinationswirkungen von Umweltchemikalien auf die Rueckstandsbildung bei Wildtieren

Feststellung messbarer Rueckstaende im Wildtier bei gleichzeitiger Aufnahme von Wirkstoff-Kombinationen aus der Nahrung und ihr Einfluss auf die Verteilung und Rueckstandsbildung im Tierkoerper. Die Umweltchemikalien werden allein und in Kombination im Koernerfutter verabreicht. In regelmaessigen Abstaenden werden Organ- und Depotfett- und Muskelproben entnommen. Die Rueckstaende werden gaschromatisch bestimmt. Ueber den gesamten Zeitraum wird mit geeigneten Parametern die biologische Leistungsfaehigkeit ermittelt. Feststellung moeglicher gegenseitiger Beeinflussung im Sinne von Synergismus oder Antagonismus.

Pflanzenschutzmittelrueckstaende in der deutschen Brotgetreideernte

a) Feststellung des Gehalts an Pflanzenschutzrueckstaenden in verschiedenen Getreidearten. Untersuchung des Abbaus bzw. des Metabolismus waehrend der Lagerung und waehrend der Verarbeitung. b) Analytische Bestimmung der Pestizide in Getreide und in Mahlprodukten in Abhaengigkeit von Lagerung und Verarbeitung einschliesslich Backprozess. Feststellung von Stoffwechselprodukten. c) Mehrjaehrige, laufende Untersuchungen in Anpassung an neue Pflanzenschutzmittel und neue analytische Verfahren.

Linear model tools for high-throughput gene expression data

Data generated from high-throughput platforms in plant-biological research are often analysed by linear model procedures. Checking model assumptions and subsequently transforming data or taking other measures to remedy violations poses a formidable task with these kinds of large datasets because of the need to automate the analysis pipeline as much as possible in order to save computing time and overall time needed for analysis. This project will develop procedures for critically inspecting and testing residuals from linear model fits. Moreover, data transformations and parametric link functions will be investigated regarding their suitability for highthroughput data. Particular emphasis will be given to transcriptome sequencing (RNAseq) using the Illumina sequencing technology and metabolite profiling. The proposed procedures will be investigated by simulation as well as by application to empirical datasets provided by our collaborators. A pipeline implementing these procedures will be developed and made available as an R-package. Computationally intensive components such as Monte Carlo simulation modules will be programmed in a low-level programming language.

Bienenschaeden und Rueckstaende in Bienenprodukten durch Pflanzenschutzmassnahmen im Obstbau

Es werden die Auswirkungen von Pflanzenschutz-Massnahmen waehrend der Obstbluete auf Bienen, Bienenbrut und Bienenprodukte in einem mehrjaehrigen Screening untersucht. Schwerpunkte bilden dabei der Einsatz von Fenoxycarb ('Insect Growth Regulator') und Streptomycin (Feuerbrand).

Optimization of a Method for the Isolation of Chloroplasts from Fresh Plant Material for the Development of a Bioassay Test for the Determination of Pesticides in Water

Bio-assays are increasingly used in supplement to classical analyses to determine the effect of contamination of waters with herbicides, some of which have been shown to be able to determine herbicides within the limits in compliance with EC-ordonance for drinking water. Preliminary work carried out at the University of Bonn has demonstrated that contamination of different water systems can be identified using inhibition of the light dependent production of oxygen by chloroplasts. Further experiments at IRMM have shown a potential to transfer membrane systems of chloroplasts into stable powder that can be used to carry out such bio-assays. Results: A method has been developed tor the isolation and breakage ot chloroplasts that allow freeze drying of the thylakoid membranes. The photosynthetic activity of the lyophilized material was maintained to 86 - 95 per cent. This powder can be stored for over five month without loss of activity.

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