Scientists are investigating a novel approach for capturing carbon in aquatic environments with low oxygen levels, like fisheries. This strategy aims to combat escalating global temperatures and may be financially viable, according to a recent study published in Nature Food.
Researchers are looking into a new way of capturing carbon in low-oxygen aquatic environments, such as fisheries. This initiative could help tackle global warming and may be cost-effective, as discussed in a recent study featured in Nature Food.
Lead researcher Mojtaba Fakhraee, an assistant professor of Earth sciences who will commence his role in August 2025, points out that conventional methods of emission reduction are inadequate for keeping global temperature rises under 2 degrees Celsius, a target established by the Paris Agreement.
Recently, scientists have focused on carbon capture—an approach that involves seizing CO2 emissions from industrial sources—as a potential method to address climate change, complementing traditional emissions reduction strategies.
Fakhraee, alongside Noah Planavsky, a professor of Earth and planetary sciences at Yale University, has developed a model to investigate how boosting alkalinity through enhanced iron sulfide formation in fish farms and similar low-oxygen environments could provide a cost-effective and efficient solution for capturing at least 100 million metric tons of CO2 each year.
“To maintain the 1.5 degree threshold, we must actively remove carbon from the atmosphere,” Fakhraee states. “This is unavoidable.”
The study emphasizes fish farms because they are significantly impacted by human action and present an excellent opportunity for carbon capture while simultaneously decreasing harmful sulfide levels.
According to their model, introducing iron— which reacts with the gathered hydrogen sulfide—boosts alkalinity. Consequently, this enhances carbonate saturation levels and improves CO2 capture from the surrounding environment.
This model could be particularly beneficial for countries such as China and Indonesia, which have many fish farms, as noted by the authors. Fakhraee and Planavsky project that China alone could potentially eliminate nearly 100 million metric tons of CO2 from the atmosphere annually.
Moreover, Fakhraee asserts that this discovery will also enhance the viability of fish farms, as the accumulation of hydrogen sulfide can be harmful to fish, resulting in higher mortality rates or fish unfit for sale. The proposed model would mitigate this toxicity, promoting healthier fish populations and more sustainable, lucrative operations.
He also mentioned that this method of carbon capture could be more effective than other techniques, as it essentially offers long-term storage of carbon.
“It is projected to be stored for thousands of years, significantly exceeding the duration of CO2 in the atmosphere,” he explains.
Fakhraee emphasizes that this is just one of many strategies for carbon capture. However, if implemented, it could greatly reduce carbon emissions from fish farms.
“This is merely one potential pathway for large-scale carbon capture,” he notes. “The added benefit of this specific method is that it would assist in neutralizing carbon emissions from fish farms, leading to a more sustainable fishing industry.”
