Aquaculture has become a booming industry in many regions of the world. According to the World Bank, nearly two-thirds of the seafood we consume will be farm-raised in 2030. However, commercial aquaculture can have negative environmental impacts, such as high nutrient waste and low oxygen environments. Integrated Multi-Trophic Aquaculture (IMTA) are managed, multi-species aquaculture systems designed to improve environmental management, and increase harvest value through product diversification and recycling of nutrients.
To achieve these benefits, all the interacting components must be understood and carefully optimized. Dr. Gregor Reid, a senior research scientist with the University of New Brunswick, used @RISK to determine the ideal ratios of kelps to uptake fish waste from a salmon IMTA system. A paper detailing this work appeared in the journal Aquaculture in May of 2013.
For his @RISK model, Reid gathered key inputs such as digestibility of salmon feed components, nutrient content of IMTA kelps, and feed composition. After running 10,000 iterations in @RISK, Reid found that “it’s not going to be possible to do full dissolved nutrient recovery with kelps in North America, unless the number of fish being farmed on site is reduced to make room for other species.” But, he says, “One-hundred percent nutrient sequestration doesn’t need to be the only successful endpoint in such systems.”