Can farmed seaweed help restore ocean ecosystems, increase resilience, and reduce greenhouse gas emissions? That was the question explored through the lens of science at a workshop we hosted earlier this month in Sacramento.
Answering this question could be valuable within the context of California’s ambitious climate, biodiversity, and restoration plans, which aim to achieve net carbon neutrality by 2045, and conserve 30% of the state’s land and coastal waters for biodiversity, climate, and access by 2030. Further, California is working to restore and adaptively manage its native bull kelp and giant kelp forests, including through developing a Kelp Restoration and Management Plan.
California’s kelp forests and other native seaweeds support healthy fisheries, biodiversity, water quality, and coastal protection, while providing cultural and recreational value. Seaweeds have been shown to locally reduce ocean acidification and eutrophication through absorbing carbon dioxide and excess nutrients, respectively.
Seaweeds also contribute to mitigating climate change. When seaweed biomass sinks to the deep sea, some of that carbon is sequestered long-term, although the magnitude, duration, and conditions under which sequestration occurs are uncertain. Seaweeds could also serve as alternative raw materials for diverse industrial uses and processes that help lower greenhouse gas emissions, such as biofuels, bioplastics, and construction materials.
A growing body of evidence is showing that seaweed farming has the potential to maintain these benefits of native seaweeds to ocean ecosystems and the climate, and even enhance them, through smart siting and strain selection, and other management practices.
This workshop brought together representatives of California agencies with mandates concerning ocean conservation, resource use, and climate change mitigation and resilience to work with scientific experts to co-create a shared understanding of the science needs and potential for farmed seaweed in California. This included discussing the state of the science and exploring uncertainties with using farmed seaweed to improve ecosystem restoration, resilience, and climate mitigation, and knowledge gaps that impede decision-making.
After a day of productive talks and discussions, Ocean Science Trust is developing a report to summarize the science shared and knowledge gaps discussed. The ultimate goal is to identify priority science needs for understanding farmed seaweed’s role in restoration, resilience, and climate change mitigation in California, and ways to address knowledge gaps.
