Short-term impact assessment of ocean liming: A copepod exposure test

Elisa Camatti; Silvia Valsecchi; Stefano Caserini; Eleonora Barbaccia; Chiara Santinelli; Daniela Basso; Arianna Azzellino

doi:10.1016/j.marpolbul.2023.115833

Short-term impact assessment of ocean liming: A copepod exposure test

Mar Pollut Bull. 2024 Jan:198:115833. doi: 10.1016/j.marpolbul.2023.115833. Epub 2023 Dec 3.

Authors

Elisa Camatti¹, Silvia Valsecchi², Stefano Caserini³, Eleonora Barbaccia⁴, Chiara Santinelli⁵, Daniela Basso⁶, Arianna Azzellino⁷

Affiliations

¹ Institute of Marine Science (ISMAR), National Research Council (CNR), Arsenale Tesa 104, Castello 2737, F-30122 Venice, VE, Italy; Institute of Biophysics (IBF), National Research Council (CNR), Via Moruzzi 1, 56124 Pisa, PI, Italy.
² Politecnico di Milano DICA Civil and Environmental Engineering Department, Piazza Leonardo da Vinci, 32, 20133 Milano, MI, Italy; Institute of Biophysics (IBF), National Research Council (CNR), Via Moruzzi 1, 56124 Pisa, PI, Italy.
³ Politecnico di Milano DICA Civil and Environmental Engineering Department, Piazza Leonardo da Vinci, 32, 20133 Milano, MI, Italy; National Inter-University Consortium for Marine Sciences CoNISMa, Piazzale Flaminio, 9, 00196 Roma, RM, Italy.
⁴ Politecnico di Milano DICA Civil and Environmental Engineering Department, Piazza Leonardo da Vinci, 32, 20133 Milano, MI, Italy.
⁵ Institute of Biophysics (IBF), National Research Council (CNR), Via Moruzzi 1, 56124 Pisa, PI, Italy.
⁶ University of Milano Bicocca DISAT, Department of Earth and Environmental Sciences, Piazza della Scienza 4, 20126 Milano, MI, Italy; National Inter-University Consortium for Marine Sciences CoNISMa, Piazzale Flaminio, 9, 00196 Roma, RM, Italy.
⁷ Politecnico di Milano DICA Civil and Environmental Engineering Department, Piazza Leonardo da Vinci, 32, 20133 Milano, MI, Italy; National Inter-University Consortium for Marine Sciences CoNISMa, Piazzale Flaminio, 9, 00196 Roma, RM, Italy. Electronic address: arianna.azzellino@polimi.it.

PMID: 38043201
DOI: 10.1016/j.marpolbul.2023.115833

Abstract

Ocean liming (OL) is a potential carbon dioxide removal (CDR) method that aims to increase the ocean's capacity to absorb atmospheric CO₂ by adding hydrated lime to the surface ocean. Modeling studies indicate that OL may cause temporary pH spikes lasting several minutes, depending on the lime sparging rate. Little is known about the short-term effects of these spikes on marine organisms. Aim of the present study is to investigate these effects on the copepod Acartia tonsa. Copepods were exposed to different pH conditions (9, 10, 11, 12) by dosing different hydrated lime solutions. Copepod mortality, movements, and behavior were recorded. At pH 9 for short exposure times (<6 h), no negative effects were observed indicating a potential tolerable threshold for OL applications. At longer exposure times (>6 h) and pH higher than 9, negative effects (mortality and sublethal effects) were found significantly higher than in the control.

Keywords: Carbon Dioxide Removal (CDR); Copepods; Ocean Alkalinity Enhancement (OAE); Ocean Liming (OL); pH toxicity.

MeSH terms

Animals
Aquatic Organisms
Carbon Dioxide / chemistry
Copepoda*

Substances

lime
Carbon Dioxide