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Found 16 results.

Cation concentrations during benthic weathering of calcite and dunite in benthocosm experiments

Enhanced benthic weathering has been proposed to serve as a efficient negative emission strategy. The precise weatherig behaviour of calcite and dunite was investigated in leng-term experiments in benthocosms. These experiments were conducted between Sept. 2022 and Sept. 2023 ashore at the Kiel Fjord. The latter are large plastic containers (~0.8 m²) that are partly filled with sediments, with constant flow-through of Baltic Sea bottom water. The sediments, obtained from Boknis Eck in the Eckernförde Bay in March 2022, were amended with calcite and dunite in triplicate (22 mol/m² equivalent) . Three additional benthocosms were left unamended to serve as controls. The used materials were obtained from Sibelco (dunite) and from the german Lime Stone Association (calcite). Samples were obtained using benthic chambers (chamber volume of 400 ml) that were placed on the sediment for three hours. Samples were taken at the beginning (_in) and at the end of the deployment (_out). All samples were filtered through a 0.2 µm cellulose membrane filter and refrigerated in 25 ml ZinsserTM scintillation vials. Acidified sub-samples (30 μl suprapure HNO3- + 3 ml sample) were prepared for analyses of major and trace elements (Si, Na, K, Li, B, Mg, Ca, Sr, Mn, Ni and Fe) by inductively coupled plasma optical emission spectroscopy (ICP-OES, Varian 720-ES).

Total alkalinity during benthic weathering of calcite and dunite in benthocosm experiments

Enhanced benthic weathering has been proposed to serve as a efficient negative emission strategy. The precise weatherig behaviour of calcite and dunite was investigated in leng-term experiments in benthocosms. These experiments were conducted between Sept. 2022 and Sept. 2023 ashore at the Kiel Fjord. The latter are large plastic containers (~0.8 m²) that are partly filled with sediments, with constant flow-through of Baltic Sea bottom water. The sediments, obtained from Boknis Eck in the Eckernförde Bay in March 2022, were amended with calcite and dunite in triplicate (22 mol/m² equivalent) . Three additional benthocosms were left unamended to serve as controls. The used materials were obtained from Sibelco (dunite) and from the german Lime Stone Association (calcite). Samples were obtained using benthic chambers (chamber volume of 400 ml) that were placed on the sediment for three hours. Samples were taken at the beginning (_in) and at the end of the deployment (_out). All samples were filtered through a 0.2 µm cellulose membrane filter and refrigerated in 25 ml ZinsserTM scintillation vials. Samples for total alkalinity (TA) were analyzed directly after sampling by titration of 1 ml of bottom water with 0.02N HCl. Titration was ended when a stable purple color appeared. During titration, the sample was degassed by continuous bubbling with nitrogen to remove any generated CO₂. The acid was standardized using an IAPSO seawater standard.

Benthic weathering of calcite and dunite in benthocosm experiments between Sept. 2022 and Sept. 2023

Enhanced benthic weathering has been proposed to serve as a efficient negative emission strategy. The precise weathering behaviour of calcite and dunite was investigated in long-term experiments in benthocosms. These experiments were conducted between Sept. 2022 and Sept. 2023 ashore at the Kiel Fjord. The latter are large plastic containers (~0.8 m²) that are partly filled with sediments, with constant flow-through of Baltic Sea bottom water. The sediments, obtained from Boknis Eck in the Eckernförde Bay in March 2022, were amended with calcite and dunite in triplicate (22 mol/m² equivalent) . Three additional benthocosms were left unamended to serve as controls. The used materials were obtained from Sibelco (dunite) and from the german Lime Stone Association (calcite). These experiments elucidate the actual weathering behavior of calcite and dunite under conditions as close to the natural system as possible. Samples were obtained using benthic chambers (chamber volume of 400 ml) that were placed on the sediment for three hours. Samples were taken at the beginning (_in) and at the end of the deployment (_out).

Mesocosm experiment on sea stars and mussels: mussel length and weight

Mesocosm experiment on sea stars and mussels: barnacle area

Mesocosm experiment on sea stars and mussels: sea stars weight parameters

Mesocosm experiment on sea stars and mussels: size, weight and consumption parameters per tank

Kiel Outdoor Benthoscosm experiment 2018 on ocean warming and upwelling: abundances of major grazer species

Abundances (numbers) of major grazer species in the tanks as assessed by subsamples taken at three time points (before upwelling 2 and 3 and between the two upwelling events).

Experimental study on common starfish Asterias rubens to heatwaves and hypoxic upwelling: measured abiotics

Experimental study on the performance of the common starfish Asterias rubens subjected to heatwaves of different duration and amplitude (No, Present-day, Extended, Amplified and Amplified & Extended heatwave) followed by a hypoxic upwelling. The study was conducted at GEOMAR, Helmholtz-Centre for Ocean Research Kiel (54.329979 N, 10.148013 E) in the Indoor Benthocosms (Pansch and Hiebenthal 2019) over 63 days from July 10th until September 10th, 2018. The implemented treatments are based on a climatological analysis of a 15-year long data set (Pansch et al. 2018). The temperature was measured over the entire experimental period (TTX 110 type T, Ebro, Ingolstadt, Germany). Salinity, pH, and oxygen concentration were measured along with the simulated upwelling event (Multi 3630 IDS, WTW, Kaiserslautern, Germany).

Kiel Outdoor Benthoscosm experiment 2018 on ocean warming and upwelling: hourly means of temperature and oxygen

Hourly means of temperature and oxygen as logged in the tanks.

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