Improving Aquaculture`s Value Through Enhanced Nutrient Management

Long-term goal: The long-term goal of this project is to develop primary, secondary, and tertiary revenue-generating production processes from the initial fish feed input required for aquaculture. We desire to improve the profitability of aquaculture and contribute to the industry's financial and environmental sustainability by developing a systems model of a large- scale aquaponics value stream that includes fish production, plant production, and bio-products produced from the production waste stream.Supporting objectives: The supporting objectives for this project are as follows:Evaluate the economic costs and savings from a sustainable, high-yield aquaponics system integrating fish, plant, and fermentation processes.Select candidate processes for fish production, plant production, algae production, waste management and treatment, and water management and treatment.Optimize linkages for all processes.Validate food safety practices in combined fish and vegetable production to
establish Good Agricultural Practices for aquaponics.Farmers engaged in aquaculture make a significant investment in feed grain, with feed amounting to some 60 percent of overall production costs (Fern, 2014; Danaher, 2016; Pickens, 2013). Fish ingest the feed and then excrete some 75 percent of the total, which is currently ignored or discarded (Boyd, 1998). Developing an optimized system to further utilize the fish waste as a way to generate additional income will improve the profitability of aquaculture and contribute to the industry's environmental sustainability. In addition to adding vegetable production by utilizing fish waste as fertilizer in an aquaponics system, we intend to explore the possibility of using the fish waste that remains in water after vegetable production to produce additional crops for food or energy value. In addition, we will investigate the possibility of using solid waste to produce valuable bioproducts, such as lactic acid via fermentation (lactic
acid is a precursor to plastic). In an international survey of aquaponics growers, Love et al (2015) found a significant relationship between sales of non-food products from aquaponics farms and the farms' profitability and suggested that aquaponics growers may want to explore revenue sources other than just vegetables and fish to enhance economic feasibility (such as the lactic acid production in this proposal).Interest in locally produced foods and sustainable production methods has increased dramatically in recent years, and for U.S.-grown fish and seafood "local" can translate to anywhere in the U.S. A national study conducted in 2003 found that an interest in healthy, safe, and fresh foods increased the likelihood of buying local foods (Zepeda and Nie, 2012). In addition, 40 percent of respondents to a 2011 trends survey conducted by the Food Marketing Institute cited knowing a foods' source as a motivation for purchasing local foods (Food Marketing Institute, 2011).
Consumers interested in "healthy, safe, and fresh" are likely to support aquaponics operations if their story is communicated to potential customers through effective marketing efforts.That is one of the many reasons why it is important to validate food safety practices in combined fish and vegetable production; at present, science-based, aquaponics-specific Good Agricultural Practices do not exist. Savidov (2004) discussed the food safety concerns expressed by consumers about aquaponics produce, with concerns being more common among the high-end consumers who are more willing to pay premium prices. Respondents expressed concerns about bacterial counts in the water, adequate testing and monitoring of bacteria, and whether bacteria from the fish product unit would get into the vegetables. We intend to answer these questions.Sustainability of the system will be assessed from the perspective of the three components of sustainability: economic (through the assessment of efficiencies as
output/input ratios of materials and energies for the system); social (through the investigation and validation of food safety and public health components of multiple production pathways); and environmental (through the elimination of pollutant effluents through re-tasking and reclamation into valuable co-products).This multidisciplinary project includes co-PIs from fisheries, horticulture, food science, and biosystems engineering. Co-PIs are already working together on this continuing project, which is partially subsidized from other sources. All have contributed to experimental design, the project work plan, and the timetable. Each also will be involved in submission of reports. PI Terrill Hanson and co-PI Jesse Chappell, both with the Auburn University School of Fisheries, Aquaculture, and Aquatic Sciences, will coordinate activities having to do with raising fish and calculating economic returns. Daniels Wells from the Horticulture Department will be responsible for raising
vegetables, Tung-shi Huang will be responsible for evaluating the safety of aquaponically raised vegetables, and David Blersch will be responsible for the lactic-acid component.