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The sustainability of aquaculture has been debated intensely since 2000, when a review on the net contribution of aquaculture to world fsh supplies was published in Nature. This paper reviews the developments in global aquaculture from 1997 to 2017, incorporating all industry sub-sectors and highlighting the integration of aquaculture in the global food system. Inland aquaculture—especially in Asia—has contributed the most to global production volumes and food security. Major gains have also occurred in aquaculture feed efciency and fsh nutrition, lowering the fsh-in–fsh-out ratio for all fed species, although the dependence on marine ingredients persists and reliance on terrestrial ingredients has increased. The culture of both molluscs and seaweed is increasingly recognized for its ecosystem services; however, the quantifcation, valuation, and market development of these services remain rare. The potential for molluscs and seaweed to support global nutritional security is underexploited. Management of pathogens, parasites, and pests remains a sustainability challenge industry-wide, and the efects of climate change on aquaculture remain uncertain and difcult to validate. Pressure on the aquaculture industry to embrace comprehensive sustainability measures during this 20-year period have improved the governance, technology, siting, and management in many cases.

A Bayesian inference method was employed to quantify uncertainty in an Integrated Multi-Trophic Aquaculture (IMTA) model. A deterministic model was reformulated as a Bayesian Hierarchical Model (BHM) with uncertainty in the parameters accounted for using “prior” distributions and unresolved time varying processes modelled using auto-regressive processes. Observations of kelp grown in 3 seeding densities around salmon pens were assimilated using a Sequential Monte Carlo method implemented within the LibBi package. This resulted in a considerable reduction in the variability in model output for both the observed and unobserved state variables. A reduction in variance between the prior and posterior was observed for a subset of model parameters which varied with seeding density. Kullback–Liebler (KL) divergence method showed the reduction in variability of the state and parameters was approximately 90%. A low to medium seeding density results in the most efficient removal of excess nutrients in this simple system.

The potential of algal biomass as a source of liquid and gaseous biofuels has been the subject of considerable research over the past few decades, with researchers strongly agreeing that algae have the potential of becoming a viable aquatic energy crop with a higher energy potential compared to that from either terrestrial biomass or municipal solid waste. However, neither microalgae nor seaweed are currently cultivated solely for energy purposes due to the high costs of harvesting, concentrating and drying. Anaerobic digestion of algal biomass could theoretically reduce costs associated with drying wet biomass before processing, but practical yields of biogas from digestion of many algae are substantially below the theoretical maximum. New processing methods are needed to reduce costs and increase the net energy balance. This review examines the biochemical and structural properties of seaweeds and of microalgal biomass that has been produced as part of the treatment of wastewater, and discusses some of the significant hurdles and recent initiatives for producing biogas from their anaerobic digestion.

The Census of Marine Life was a 10-year, international research effort to explore poorly known ocean habitats and conduct large-scale experimentation with new technology. The goal of Census 2010 in its mission statement was to describe what did live in the oceans, what does live in the oceans, and what will live in the ocean. Many of the findings and techniques from census research may prove valuable in making a transition, which many governments have publicly endorsed, from single-species fisheries management to more holistic ecosystem management. Census researchers sampled continental margins, mid-Atlantic ridges, ocean floor vents and seeps, and abyssal plains and polar seas and organized massive amounts of past and new information in a public online database called the Ocean Biogeographic Information System (www.iobis. org). The census described and categorized seamount biology worldwide for its vulnerability to fishing, advanced large-scale animal tracking with acoustic arrays and satellite archival tags, and accelerated species identification, including nearshore, coral reef, and zooplankton sampling using genetic barcoding and pyrotag sequencing for microbes and helped to launch the exciting new field of marine environmental history. Above all, the census showed the value of investing in large-scale, collaborative projects and sharing results publicly.