Suessle, Philipp; Schulz, Kai Georg; Barcelos e Ramos, Joana; Sievers, Nico Manuel; Riebesell, Ulf: KOSMOS 2023 Helgoland mesocosm study on ocean alkalinity enhancement: sediment trap particle flux data and water column biogeochemistry [dataset]. PANGAEA, https://doi.pangaea.de/10.1594/PANGAEA.992023 (dataset in review)
Abstract:
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.
Keyword(s):
Supplement to:
Suessle, Philipp; Schulz, Kai Georg; Barcelos e Ramos, Joana; Sievers, Nico Manuel; Schneider, Julieta; Tammen, Juliane Katharina; Kittu, Leila; Marín-Samper, Laura; Riebesell, Ulf (in prep.): Ocean alkalinity enhancement reduces silica ballasting during export due to amplified dissolution.
References:
Bach, Lennart Thomas; Riebesell, Ulf; Sett, Scarlett; Febin, Sarah; Rzepka, Paul; Schulz, Kai Georg (2012): An approach for particle sinking velocity measurements in the 3–400 µm size range and considerations on the effect of temperature on sinking rates. Marine Biology, 159(8), 1853-1864, https://doi.org/10.1007/s00227-012-1945-2
Bryan, J R; Rlley, J P; Williams, P J Leb (1976): A winkler procedure for making precise measurements of oxygen concentration for productivity and related studies. Journal of Experimental Marine Biology and Ecology, 21(3), 191-197, https://doi.org/10.1016/0022-0981(76)90114-3
Carrit, D E; Carpenter, J H (1966): Recommendation procedure for winkler analysis of seawater for dissolved oxygen. Journal of Marine Research, 24, 313–318
Grasshoff, Klaus; Kremling, Klaus; Ehrhardt, M (1999): Methods of Seawater Analysis. Wiley, https://doi.org/10.1002/9783527613984
Hansen, Hans Peter; Koroleff, F (1999): Determination of nutrients. In: Grasshoff, Klaus; Kremling, Klaus; Ehrhardt, Manfred (eds.), Methods of Seawater Analysis, Wiley-VCH Verlag GmbH, Weinheim, Germany, 159-226, https://doi.org/10.1002/9783527613984.ch10
Marie, Dominique; Brussaard, Corina P D; Thyrhaug, Runar; Bratbak, Gunnar; Vaulot, Daniel (1999): Enumeration of Marine Viruses in Culture and Natural. Applied and Environmental Microbiology, 65(1), 45-52, https://doi.org/10.1128/AEM.65.1.45-52.1999
Pierrot, Denis; Epitalon, Jean-Marie; Orr, James C; Lewis, E; Wallace, D W R (2021): MS Excel program developed for CO2 system calculations – version 3.0. GitHub repository, https://github.com/dpierrot/co2sys_xl
Sharp, Jonathan H (1974): Improved analysis for "particulate" organic carbon and nitrogen from seawater1. Limnology and Oceanography, 19(6), 984-989, https://doi.org/10.4319/lo.1974.19.6.0984
Project(s):
Funding:
Federal Ministry of Education and Research (BMBF), grant/award no. 03F0895A: DAM CDRmare - RETAKE, GEOMAR
Coverage:
Latitude: 54.183300 * Longitude: 7.900000
Date/Time Start: 2023-03-14T00:00:00 * Date/Time End: 2023-04-21T00:00:00
Event(s):
KOSMOS_2023_Mesocosm-M1 * Latitude: 54.183300 * Longitude: 7.900000 * Date/Time Start: 2023-03-14T00:00:00 * Date/Time End: 2023-04-21T00:00:00 * Location: Helgoland * Campaign: KOSMOS_2023 (KOSMOS Helgoland) * Method/Device: Mesocosm experiment (MESO)
KOSMOS_2023_Mesocosm-M2 * Latitude: 54.183300 * Longitude: 7.900000 * Date/Time Start: 2023-03-14T00:00:00 * Date/Time End: 2023-04-21T00:00:00 * Location: Helgoland * Campaign: KOSMOS_2023 (KOSMOS Helgoland) * Method/Device: Mesocosm experiment (MESO) * Comment: delayed treatment
KOSMOS_2023_Mesocosm-M3 * Latitude: 54.183300 * Longitude: 7.900000 * Date/Time Start: 2023-03-14T00:00:00 * Date/Time End: 2023-04-21T00:00:00 * Location: Helgoland * Campaign: KOSMOS_2023 (KOSMOS Helgoland) * Method/Device: Mesocosm experiment (MESO)
Comment:
Details regarding mesocosm set-up:
The floating mesocosms were made of a transparent 1mm thick polyurethane bag with a cylindrical upper section and a conical sediment trap at the bottom, extending to 3.5 m depth. The bags were mounted on floating frames and enclosed a water volume of ~6m³. The mesocosms were filled simultaneously with seawater pumped from 2-3 m depth outside the harbour using a peristaltic pump, larger organisms were excluded via pre-filtration with a 3 mm mesh.
Parameter(s):
| # | Name | Short Name | Unit | Principal Investigator | Method/Device | Comment |
|---|---|---|---|---|---|---|
| 1 | Type of study | Study type | Suessle, Philipp | |||
| 2 | Event label | Event | Suessle, Philipp | |||
| 3 | Sample code/label | Sample label | Suessle, Philipp | |||
| 4 | DATE/TIME | Date/Time | Suessle, Philipp | Geocode | ||
| 5 | Day of experiment | DOE | day | Suessle, Philipp | ||
| 6 | Treatment | Treat | Suessle, Philipp | Imm or Del respectivley, refer to the treatment application meaning alkalinity was either immediately (Imm) diluted (i.e., spread evenly throught the water column of the mesocosm) OR it was added to the top layer of the mesocosm only and the only diluted, mixed into the entire water column later, meaning delayed (Del). For each, immediate or delayed application scenario, there were six alkalinity levels in increments of 250 µmol TA per kg, ranging from zero alkalinity addition (e.g. Imm/0 or Del/0) to 1250 µmol TA per kg (e.g. Imm/1250 or Del/1250). | ||
| 7 | Water depth description | Water depth descr | Suessle, Philipp | Sample layer: On all sampling days, integrated water samples from 0-2.5 m were taken, with the exception of the layer phase on day 5 and day 6. On these two days, the top layer (0-1m) and the bottom layer (1-2.5m) were sampled separately in the delayed dilution treatment (marked as top and bottom). | ||
| 8 | Alkalinity, total | AT | µmol/kg | Suessle, Philipp | Titration device, Metrohm, 862 Compact Titrosampler [with built-in PT1000 temperature sensor] | TA, measured in duplicates by two-stage open-cell potentiometric titration using hydrochloric acid (0.05 mol L-1) |
| 9 | Carbon, inorganic, dissolved | DIC | µmol/kg | Suessle, Philipp | Automated Infra Red Inorganic Carbon Analyzer (AIRICA), MARIANDA; coupled with Differential infrared gas analyzer, LI-COR Biosciences, LI-7000 | determined in triplicates via infrared absorption |
| 10 | pH | pH | Suessle, Philipp | Calculated using the CO2sys_v3.0 software (Pierrot et al. 2021) | applying water column–averaged temperature and salinity measurements from CTD profiles, as well as dissolved phosphorous and silicate concentrations for corrections | |
| 11 | Fugacity of carbon dioxide | fCO2 | µatm | Suessle, Philipp | Calculated using the CO2sys_v3.0 software (Pierrot et al. 2021) | applying water column–averaged temperature and salinity measurements from CTD profiles, as well as dissolved phosphorous and silicate concentrations for corrections |
| 12 | Fucoxanthin | Fuco | ng/l | Suessle, Philipp | High-performance liquid chromatography (HPLC), Thermo Scientific, UltiMate 3000 | |
| 13 | Carbon, organic, particulate, flux per day | POC flux | µmol/l/day | Suessle, Philipp | Carbon nitrogen elemental analyzer, HEKAtech, EURO EA-CN | sample measurement in duplicates with a CN analyzer (Euro EA-CN, HEKAtech GmbH, Germany) according to Sharp (1974), subsequent flux calculation from mesocosm volume and sedimentation time |
| 14 | Nitrogen, organic, particulate, flux per day | PON flux | µmol/l/day | Suessle, Philipp | Carbon nitrogen elemental analyzer, HEKAtech, EURO EA-CN | sample measurement in duplicates with a CN analyzer (Euro EA-CN, HEKAtech GmbH, Germany) according to Sharp (1974), subsequent flux calculation from mesocosm volume and sedimentation time |
| 15 | Phosphorus, organic, particulate, flux per day | POP flux | µmol/l/day | Suessle, Philipp | Spectrophotometer; according to Hansen & Koroleff (1999) | measured spectrophotometrically, subsequent flux calculation from mesocosm volume and sedimentation time |
| 16 | Carbon, inorganic, particulate, flux per day | PIC flux | µmol/l/day | Suessle, Philipp | Calculated | Concentrations of particulate inorganic carbon flux were calculated as the difference between total particulate carbon flux and particulate organic carbon flux. |
| 17 | Biogenic silica, flux per day | bSiO2 flux | µmol/l/day | Suessle, Philipp | Spectrophotometer; according to Hansen & Koroleff (1999) | measured spectrophotometrically, subsequent flux calculation from mesocosm volume and sedimentation time |
| 18 | Equivalent spherical diameter | ESD | µm | Suessle, Philipp | Video-microscopy according to Bach et al. (2012) | Average of all measured particles in size-class 100-250 µm |
| 19 | Particle porosity | Particle poros | Suessle, Philipp | Video-microscopy according to Bach et al. (2012) | Average of all measured particles in size-class 100-250 µm | |
| 20 | Sinking velocity | Sinking V | m/day | Suessle, Philipp | Video-microscopy according to Bach et al. (2012) | Average of all measured particles in size-class 100-250 µm |
| 21 | Bacteria | Bact | #/ml | Suessle, Philipp | Flow cytometer, BD Biosciences, FACSCalibur | cells per ml, following the bacterioplankton protocol of Marie et al. (1999) |
| 22 | Respiration rate, oxygen, community | Comm resp O2 | µmol/l/day | Suessle, Philipp | determined from oxygen consumption following the Winkler method and recommendations by Bryan et al. (1976), Carritt and Carpenter (1966) and Grasshoff et al. (1999). |
License:
Creative Commons Attribution 4.0 International (CC-BY-4.0) (License comes into effect after moratorium ends)
Status:
Curation Level: Enhanced curation (CurationLevelC)
Size:
4954 data points
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