Aquatic foods from farming in marine and freshwater systems contribute significantly to food and nutritional security, while supporting livelihoods, economic growth and human well-being around the world. To meet the growing aquatic food demand, aquaculture intensification, often through monocultures using pelleted feeds and agrochemical inputs, poses a risk to maintaining planetary sustainability boundaries. Diversified aquaculture systems, which intentionally increase the number of aquaculture and non-aquaculture farm species, are a promising strategy to bring about more sustainable food production because in theory they offer an ecological mechanism for higher resource use efficiency. However, existing views also suggest that monoculture is preferable to polyculture from a sustainability perspective. Despite a rapidly growing body of research assessing the impacts of aquaculture diversification on several dimensions of environmental and social outcomes, there is no comprehensive global quantitative synthesis of this information. In more detail, literature is divided in terms of the environmental and social benefits of diversified versus specialized aquaculture systems. This study conducts a meta-analysis of the peer-reviewed literature on the environmental and social outcomes of diversified aquaculture systems. We examine how diversification influences multiple environmental and social outcomes while highlighting trade-offs and/or synergies within and between environmental and social outcomes. Sub-group analyses including study scales (i.e., farm, landscape, and national levels), aquaculture systems and species (i.e., marine finfish, marine bivalves, marine algae, marine/brackish pond, pond finfish, pond crabs, pond prawns, cage finfish) are conducted to differentiate environmental and social performance. This study will deliver a global synthesis of environmental and social outcomes of diversified versus specialized aquaculture systems, providing a broader understanding of their trade-offs and/or synergies across diverse contexts.

aquatic foods,auqaculture diversification,sustainability,systematic review & meta-analysis