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Elbe Element Explorer 2018-2023: A time series of dissolved metals in the Elbe river

The river Elbe flows through Geesthacht right before the tidal part of the Elbe begins. In order to monitor and investigate the metal load and transport from the upstream river with a study focus on extreme events, water samples were taken weekly from the Geesthacht riverbank a couple of kilometers upstream of the weir starting in April 2018 and going until April 2023. During extreme events, i.e. floods or droughts, the sampling interval was increased to (bi-)daily sampling. The water samples were taken in pre-cleaned LDPE bottles, filtered over <0.45 µm polycarbonate filters into pre-cleaned LDPE bottles/tubes and acidified with nitric acid. The filtrates were then measured for their (trace) metal concentrations with ICP-MS/MS coupled online to a seaFAST preconcentration and matrix removal system. The physiochemical parameters pH value, dissolved oxygen, temperature and conductivity were measured for each sample using a corresponding multimeter probe.

Abundance of Prokaryotes in deep-sea sediments analyzed by CARD-FISH

We fixed 0.5 g aliquots of sediment with a 4% formaldehyde solution for 2-4 h, washed the fixed sediments three times with 1x phosphate-buffered saline (PBS), before storing them in 50% ethanol/PBS at -20°C. For water samples, we fixed 10 ml (for samples from the deep chlorophyll maximum and 100 m water depth) and 30 ml (for meso- and bathypelagic samples) with formaldehyde to a final concentration of 2-4% for 2-4 h, then filtered over a 0.22 µm polycarbonate filter, and stored samples at -20°C. We performed total cell counts as described by Schauer et al. (2011, doi:10.1111/j.1462-2920.2011.02530.x) using the nucleic acid dye 4'-6-diamidino-2-phenylindole (DAPI). A minimum of 1,000 cells in 20 independent grids were counted using a Zeiss Axio Imager M1 epifluorescence microscope equipped with a 100x/1.25 oil plan-apochromat objective. We used Catalyzed Reporter Deposition-Fluorescence In Situ Hybridization (CARD-FISH) according to Ishii et al. (2004) to count Gammaproteobacteria and JTB255 cells. We used the GAM42a oligonucleotide probe and the BET42a competitor probe to target members of the Gammaproteobacteria (Manz et al., 1992, doi:10.1016/S0723-2020(11)80121-9). We designed the JTB819a and JTB897 probes to target 16S rRNA gene sequences assigned to JTB255 in SILVA release 128 and the cJTB897 competitor probe to target all non-JTB255 16S sequences in SILVA release 128 that have a single mismatch to JTB819a and JTB897 probes. We obtained total gammaproteobacterial and JTB255 cell counts from duplicate filters derived from each sampling site.

Extracellular dissolved organic carbon (DOC) concentrations in axenic and xenic cultures of Thalassiosira gravida in response to varying temperatures and photoperiods

This dataset comprises dissolved organic carbon (DOC) concentrations from axenic and xenic cultures of Thalassiosira gravida that were cultivated at the Alfred-Wegener-Institute (Bremerhaven, Germany) in March, 2023. After a cell density of ~ 15.000 cells * mL-1 was reached, cultures were filtered through a 0.2 µm polycarbonate (PC) filter (Whatman) that was cleaned by soaking in 10 % hydrochloric acid (HCl, Merck suprapure) for at least 12 h and subsequently rinsing with ultrapure water (Merck Millipore MilliQ). DOC was quantified by high temperature catalytic oxidation with a Shimadzu TOC analyzer (VCPN-TOC, Shimadzu) according to Garzón-Cardona et al. 2024; doi: 10.1016/J.JMARSYS.2023.103893. Cultures were grown under two temperatures (9 °C, 13.5 °C) and two photoperiods (16:8 h, 24:0 h light:dark). The aim was to investigate responses of algal extracellular release and bacterial DOC transformation to marine heatwave-like conditions.

Dissolved organic matter (DOM) composition in axenic and xenic cultures of Thalassiosira gravida in response to varying temperatures and photoperiods

This dataset comprises dissolved organic matter (DOM) composition from axenic and xenic cultures of Thalassiosira gravida that were cultivated at the Alfred-Wegener-Institute (Bremerhaven, Germany) in March, 2023. After a cell density of ~ 15.000 cells * mL-1 was reached, cultures were filtered through a 0.2 µm polycarbonate (PC) filter (Whatman) that was cleaned by soaking in 10 % hydrochloric acid (HCl, Merck suprapure) for at least 12 h and subsequently rinsing with ultrapure water (Merck Millipore MilliQ). Cultures were grown under two temperatures (9 °C, 13.5 °C) and two photoperiods (16:8 h, 24:0 h light:dark). 2 mL of the sample were filtered through a 0.2 µm regenerated cellulose (RC)-membrane syringe filter (Sartorius) after defrosting. Molecular composition data were acquired with Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) coupled to a reversed-phase liquid chromatography (RPLC) with negative electrospray ionization (ESI) according to Lechtenfeld et al., 2024 (doi: 10.1021/acs.est.3c07219). Measurements were performed on on a solariX XR, Bruker Daltonics, Billerica, U.S.A. at the Helmholtz Centre for Environmental Research (UFZ; Leipzig, Germany). Molecular formulas were assigned and filtered using UltraMassExplorer (Leefmann et., 2019; doi: 10.1002/rcm.8315). If the Total ion chromatogram (TIC) was much higher and/or different in certain retention time windows compared to other samples of the same treatment, the sample was excluded from the dataset. The aim of this study was to investigate responses of algal extracellular release and bacterial DOM transformation to marine heatwave-like conditions.

Microbial community composition in fresh water at different stations

Fluorescence in situ hybridization (FISH) with rRNA-targeted oligonucleotide probes was used to investigate the phylogenetic composition of bacterioplankton communities in several freshwater and marine samples. An average of about 50% of the cells were detected by probes for the domains Bacteria and Archaea. Cells were concentrated from water samples (1 to 100 ml) on white polycarbonate filters (diameter, 47 mm; pore size, 0.2 mm; type GTTP 4700 [Millipore, Eschborn, Germany]) by applying a vacuum of <25 kPa. They were subsequently fixed by covering the filter with 3 ml of a freshly prepared, phosphate-buffered saline (pH 7.2)-4% paraformaldehyde (Sigma, Deisenhofen, Germany) solution for 30 min at room temperature. Airdried filters are ready for hybridization and can be stored at 220°C or room temperature for several months without showing apparent changes. Probes BET42a, GAM42a, and PLA886 were used with competitor oligonucleotides as described previously amongst others in Manz et al., (1992; doi:10.1016/S0723-2020(11)80121-9). The filters were transferred to a vial containing 50 ml of prewarmed (48°C) washing solution (70 mM NaCl, 20 mM Tris-HCl [pH 7.4], 5 mM EDTA, 0.01% sodium dodecyl sulfate) and incubated freely floating without shaking at 48°C for 15 min. The filter sections were dried on Whatman 3M paper (Whatman Ltd., Maidstone, United Kingdom) and covered with 50 ml of DAPI solution (1 mg/ml in distilled water filtered through at 0.2-mm filter) for 5 min at room temperature in the dark. For each sample and probe, more than 500 cells were enumerated; for the DAPI examination, more than 1,500 cells were counted per sample. All probe-specific cell counts are presented as the percentage of cells visualized by DAPI. The mean abundances and standard deviations were calculated from the counts of 10 to 20 randomly chosen fields on each filter section. All counts were corrected by subtracting the counts obtained with the negative control NON338. Mean and standard deviation were calculated from the counts of 10 to 20 randomly chosen fields on each filter section.

Hochgeschwindigkeitsextrusion amorpher Polymere am Beispiel von Polycarbonat (PC) und Polymethylmethacrylat (PMMA)

Bioethanol to Acetone - Chemische und biotechnologische Prozessentwicklung zur Erschließung nachhaltiger Feedstocks, BETA - Bioethanol to Acetone - Chemische und biotechnologische Prozessentwicklung zur Erschließung nachhaltiger Feedstocks

Copper in sediment, water and suspended particulate matter of the tidal influenced part of the Elbe River sampled in April 2023 (LP20230402)

Legacy pollutants (e.g. Cu) are well studied and known to deposit in regions of sedimentation along rivers like the Elbe River located in northern Germany. However, in order to help authorities to maintain rivers as important economic transport routes numerical models are used to forecast possible pollution transportation after dredging or sediment relocation. To improve the precision of such models, valid data related to the pollution partitioning behavior and constant model validation is needed. Sediment, water and suspended particulate matter (SPM) were sampled during a sampling campaign in April 2023 and analyzed within the context of the cooperation project CTM-Elbe of BAW and Hereon. The sediment samples were taken by a box corer, homogenized, freeze-dried and wet-sieved to gain the <63 µm grain size fraction. The <63 µm grain size fraction was acid digested and measured by ICP-MS/MS for their (trace) metal mass fractions. The high-volume water samples were centrifuged with a continuous flow centrifuge (CFC) to separate the SPM from the water phase before the SPM samples were freeze-dried. The obtained SPM samples were treated analogously to the sieved sediment samples. The water samples were taken in metal-free GO-FLO sampling bottles and filtered over <0.45 µm polycarbonate filters in the laboratory before acidification with nitric acid. The filtrates were then measured for their (trace) metal concentrations with ICP-MS/MS coupled online to a seaFAST preconcentration and matrix removal system. This data set provides the Cu mass fractions in the fine grain sediment fraction of the SPM together with dissolved (<0.45 µm) Cu concentrations in the water.

TemBi 2014 mesocosm study: Summer storm impact on size-fractionated bacterial protein production and abundance of heterotrophic prokaryotes and picocyanobacteria

We simulated an experimental summer storm in large-volume (~1200 m³, ~16m depth) enclosures in Lake Stechlin (https://www.lake-lab.de) by mixing deeper water masses from the meta- and hypolimnion into the mixed layer (epilimnion). The mixing included the disturbance of a deep chlorophyll maximum (DCM) which was present at the same time of the experiment in Lake Stechlin and situated in the metalimnion of each enclosure during filling. Size-fractionated Bacterial Protein Production (BPP) of particle associated (PA, >3.0 µm) and free-living bacteria (FL, 0.2-3.0 µm) (14C-Leu incorporation) as well as abundances of PA (microscopy of DAPI stained cells on 3.0 µm polycarbonate filters) and FL heterotrophic prokaryotes and picocyanobacteria (flow cytometry of SYBR green I stained cells) were monitored for 42 days after the experimental disturbance event. Mixing increased bacterial abundance and production about 3 weeks after mixing, which was associated to a mixing-induced stimulation of phytoplankton growth in the mixed enclosures compared to the controls. Simultaneously, decreased abundances of picocyanobacteria could be observed in mixed enclosures.

Trace metal distribution for water samples of the cruise AT010

Offshore wind energy is a steadily growing sector contributing to the worldwide energy production. The impact of these offshore constructions on the marine environment, however, remains unclear in many aspects. In fact, little is known about potential emissions from corrosion protection systems such as organic coatings or galvanic anodes composed of Al and Zn alloys, used to protect offshore structures. In order to assess potential chemical emissions from offshore wind farms and their impact on the marine environment water and sediment samples were taken in and around offshore wind farms of the German Bight between 04.04.2022 and 14.04.2022 within the context of the Hereon-BSH project OffChEm II. The water samples were taken in metal-free GO-FLO sampling bottles, filtered over <0.45 µm polycarbonate filters into pre-cleaned LDPE bottles and acidified with nitric acid. The filtrates were then measured for their (trace) metal concentrations with ICP-MS/MS coupled online to a seaFAST preconcentration and matrix removal system.

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