KOSMOS 2021 Gran Canaria mesocosm study on ocean alkalinity enhancement: phytoplankton metabolic rates ...

• Main Authors: Marín-Samper, Laura, Arístegui, Javier, Hernández-Hernández, Nauzet, Ortiz Cortes, Joaquin, Archer, Stephen, Ludwig, Andrea, Riebesell, Ulf
• Format: Dataset
• Language: unknown
• Published: PANGAEA 2024
• Subjects: 14C-DOC; 14C-POC; chlorophyll-a concentration; Field experiment; flow cytometry; mesocosm experiment; primary production; Winkler oxygen; Type of study; Event label; Day of experiment; Treatment alkalinity, total; Mesocosm label; Identification; Depth, water, experiment, top/minimum; Depth, water, experiment, bottom/maximum; Primary production of carbon, organic, particulate; Primary production of carbon, organic, dissolved; Primary production of carbon, organic, total; Extracellular release; Chlorophyll a, total; Chlorophyll a picoplankton; Chlorophyll a nanoplankton; Chlorophyll a microplankton; Synechococcus; Picoeukaryotes; Nanoeukaryotes; Net community production of oxygen; Respiration rate, oxygen, community; Gross community production of oxygen; Gross community production/respiration rate, oxygen, ratio; Mesocosm experiment; 14C uptake; Flow cytometry; KOSMOS_2021; Network of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the Arctic to the Mediterranean AQUACOSM; Ocean-based Negative Emission Technologies OceanNETs; Ocean acidification; Phytoplankton
• Online Access: https://dx.doi.org/10.1594/pangaea.964537; https://doi.pangaea.de/10.1594/PANGAEA.964537

Ocean Alkalinity Enhancement (OAE) could augment long-term carbon storage and mitigate ocean acidification by increasing the bicarbonate ion concentration in ocean water. However, the side effects and/or potential co-benefits of OAE on natural planktonic communities remain poorly understood. To address this knowledge gap, 9 mesocosms were deployed in the oligotrophic waters of Gran Canaria, from September 14th to October 16th, 2021. A CO2-equilibrated Total Alkalinity (TA) gradient was employed in increments of 300 µmol·L-1, ranging from ~2400 to ~4800 µmol·L-1. The carbonate chemistry conditions in terms of TA and Dissolved Inorganic Carbon (DIC), which were then used to calculate pCO2 and pH, and the nitrate+nitrite, phosphate and silicate concentrations were measured every two days over the course of the 33-day experiment alongside the following biotic parameters. Net Community Production (NCP), Gross Production (GP), Community Respiration (CR) rates, as well as the metabolic balance (GP:CR), were ...