Advances in Swedish Seaweed Aquaculture: Enhancing Biomass Production and Quality

Abstract

Seaweed aquaculture is rapidly growing globally and offers environmental benefits such as reducing eutrophication and increasing biodiversity. Sweden has a long coast with favorable conditions for seaweed cultivation, but the current industry remains small. Over the past decade, several innovative research projects have explored and developed techniques tailored toward sustainable seaweed aquaculture. This study synthesizes recent advances in Swedish seaweed aquaculture research, highlighting innovations that support biomass yield and quality. We conducted a systematic review of 130 studies from the Thomson Reuters Web of Science, focusing on Swedish seaweed aquaculture research, and ultimately included 21 relevant publications from 1984 to 2025. The main seaweed species cultivated in Sweden are the brown seaweed Saccharina latissima and the green seaweed Ulva fenestrata. Key strategies to enhance biomass productivity, quality, and sustainability include optimizing land-based juvenile preparation, careful selection of cultivation sites, and strategic timing of sea-based harvests. Innovative approaches like the utilization of nutrient-rich process waters from food production offer sustainable methods to boost yield and protein content, aligning seaweed cultivation with circular economy principles. Future development and optimization of cultivation protocols for other protein-rich seaweed species (e.g., Palmaria palmata) or species that tolerate lower salinity (e.g., Fucus vesiculosus or U. intestinalis) will be critical to maximize the potential of Swedish seaweed cultivation, ensuring its effective contribution to food security and environmental conservation. As commercial interest in seaweed continues to grow, findings summarized here provide a robust foundation for the expansion of seaweed aquaculture in Europe and beyond.