KOSMOS 2022 Bergen mesocosm study on ocean alkalinity enhancement: phytoplankton metabolic rates

DOI

Ocean alkalinity enhancement (OAE) is a marine carbon dioxide removal (mCDR) with the potential to remove atmospheric CO2 and increase the ocean's buffering capacity. Thus, it may aid in mitigating global warming and ocean acidification. Depending on the source mineral type (if silicate or calcium-based) and on if implemented in a pre- or non-equilibrated way, impacts on the microbial community's metabolic rates can be expected. The mineral type may introduce compounds to the system that may benefit certain phytoplankton species over others, and if non-equilibrated, changes to the pCO2 and pH may hinder primary production. To address this, an experiment with 10 pelagic mesocosms was undertaken, starting on the 7th May 2022. Two 5-step non-equilibrated TA gradients in increments of 150 µmol L-1 were implemented. One simulated a forsterite [Mg2SiO3] addition, and the other one a hydrated lime [Ca(OH)2] addition. Gross production (GP), net community production (NCP), community respiration (CR), and community metabolic balance (GP:CR), measured in vitro through oxygen production and consumption, as well as chlorophyll a, were monitored over a 53-day long period. All the biogeochemical parameters relevant to their response were measured as well. After a nutrient addition undertaken halfway through the experiment, a delay in bloom formation associated with the TA manipulation was observed. This is likely due to the previously reported, species-specific responses to low pCO2 and high pH conditions in terms of growth rates. Further research will be necessary to evaluate the implications of this findings with regards to trophic transfer, and seasonal suitability.

Identifier
DOI https://doi.pangaea.de/10.1594/PANGAEA.972371
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.972371
Provenance
Creator Marín-Samper, Laura ORCID logo; Arístegui, Javier ORCID logo; Hernández-Hernández, Nauzet ORCID logo; Riebesell, Ulf (ORCID: 0000-0002-9442-452X)
Publisher PANGAEA
Publication Year 2024
Funding Reference Horizon 2020 https://doi.org/10.13039/501100007601 Crossref Funder ID 731065 https://cordis.europa.eu/project/id/731065 Network of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the Arctic to the Mediterranean; Horizon 2020 https://doi.org/10.13039/501100007601 Crossref Funder ID 869357 doi:10.3030/869357 OceanNETs: Ocean-based Negative Emission Technologies
Rights Creative Commons Attribution 4.0 International; Data access is restricted (moratorium, sensitive data, license constraints); https://creativecommons.org/licenses/by/4.0/
OpenAccess false
Representation
Resource Type Dataset
Format text/tab-separated-values
Size 3144 data points
Discipline Earth System Research
Spatial Coverage (5.206 LON, 60.265 LAT)
Temporal Coverage Begin 2022-05-14T00:00:00Z
Temporal Coverage End 2022-07-05T00:00:00Z