Sustainable Blue Foods from Rice–Animal Coculture Systems

Global
interest grows in blue foods as part of sustainable diets,
but little is known about the potential and environmental performance
of blue foods from rice–animal coculture systems. Here, we
compiled a large experimental database and conducted a comprehensive
life cycle assessment to estimate the impacts of scaling up rice–fish
and rice–crayfish systems in China. We find that a large amount
of protein can be produced from the coculture systems, equivalent
to ∼20% of freshwater aquaculture and ∼70% of marine
wild capture projected in 2030. Because of the ecological benefits
created by the symbiotic relationships, cocultured fish and crayfish
are estimated to be carbon-negative (−9.8 and −4.7 kg
of CO2e per 100 g of protein, respectively). When promoted
at scale to displace red meat, they can save up to ∼98 million
tons of greenhouse gases and up to ∼13 million hectares of
farmland, equivalent to ∼44% of China’s total rice acreage.
These results suggest that rice–animal coculture systems can
be an important source of blue foods and contribute to a sustainable
dietary shift, while reducing the environmental footprints of rice
production. To harvest these benefits, robust policy supports are
required to guide the sustainable development of coculture systems
and promote healthy and sustainable dietary change.