Macroalgae (seaweed) aquaculture can potentially remove over 75,000 tons of nitrogen per year by producing 2 million tons (DW) of seaweed. The potential for using macroalgae for bioremediation is accordingly huge. In Norway, the idea has primarily been to use for macroalgae (kelp) in integrated multi-trophic aquaculture (IMTA) where species from lower trophic levels (e.g kelp) are co-cultured with fed species (e.g salmon) to utilise the waste nutrients. Co-producing salmon and kelp reduces the ecological impact of dissolved nitrogen and phosphorous released into the environment from salmon farming and has been suggested as a strategy to mitigate the potentially negative environmental impacts from salmon aquaculture. IMTA produces valuable low trophic biomass based on nutrient resources that would otherwise be lost or wasted.
SINTEF develops new technology for up-scaling IMTA-farms for co-cultivation of salmon and kelp and have a broad competence along the whole value chain of seedlings production, sea-farming, harvesting, chemical characterisation, storage, processing, product development and climate positive applications.