Maximizing nutrient recovery from aquaponics wastewater with autotrophic or heterotrophic management strategies. (February 2023)

• Record Type: Journal Article
• Authors: Chen, Peng; Kim, Hye-Ji; Thatcher, Luke Raymond; Hamilton, Joshua Michael; Alva, Makayla L.; Zhou, Zhi; Brown, Paul B.
• Is Part Of: Bioresource technology reports. Volume 21(2023)
• Publication Date: 2023-02
• Subjects: pH -- Sustainable food -- Environmental engineering -- Ammonia assimilation -- Nitrification -- Aquaponics; Biomass energy -- Periodicals; Biotransformation (Metabolism) -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Waste products as fuel -- Periodicals; Waste products as fuel; Organic wastes; Factory and trade waste; Biotransformation (Metabolism); Biomass energy; Agricultural wastes; Periodicals; Electronic journals; 662.88
• DOI: 10.1016/j.biteb.2023.101360
• Languages: English
• ISSNs: 2589-014X

Abstract

Abstract: Aquaponics uses bacterial processes and plant nutrient uptake to recover nutrients from aquaculture wastewater. However, little is known about which wastewater management strategy is best suited for nutrient recovery. We compared four aquaponics water management strategies: pH 6 or pH 7 with autotrophic bacterial populations (pH 6, pH 7), and pH 6 or 7 with heterotrophic bacterial populations (pH6M, pH 7 M). The results indicated that nutrients recovered with greater efficiency in pH 6 and pH 6 M than in pH 7, with higher plant biomass and food quality. pH 6 displayed the highest nitrogen (N) use efficiency (NUE = 65.5 %) and the lowest N loss as gas (34.5 %), followed by pH 6 M, suggesting that lower pH in aquaponics could enhance NUE and reduce N loss. pH 6 M had the highest phosphorus (P) use efficiency (PUE = 65.0 %) suggesting that lower pH and heterotrophic bacterial populations facilitate P recovery from wastewater. Plant nutrient uptake was improved when heterotrophic bacterial populations were established in an environmental pH of 6. Graphical abstract: Unlabelled Image Highlights: Rapid aquaponics startup without running traditional nitrogen cycle is achievable. Treatments w/wo organic carbon in aquaponics were compared in two pH levels. Productivity was sustained despite the weak nutrient strength in all treatments. pH 6 heterotrophic systems have higher P recovery, plant productivity and quality. Future aquaponics should set pH at 6 and shift to heterotrophic strategies.