The complex microbiome in aquaponics: significance of the bacterial ecosystem

Abstract

Purpose: Aquaponics is a technology that has minimal impact on the environment and which is often promoted as a solution for sustainable food production. Developing aquaponics sustainably requires a thorough understanding of the biological components of the system. Recent reports on the bacterial populations of aquaponics systems using new DNA sequencing technologies are revealing a complex and diverse microbial ecosystem. The purpose of this review is to present information on microbial composition and various factors affecting bacterial activity in aquaponics systems. Approaches for establishing a bacterial ecosystem during the setup of an aquaponics system, and microbiological safety of aquaponics products are also highlighted. Methods: This review was developed by evaluating and synthesising current literature of peer-reviewed publications related to aquaponics and microbial communities. Based on the results from credible academic journals, publications were categorised into five groups: methods used to characterise microbiomes, biofiltration microorganisms, bacterial diversity, biofilter establishment, and safety of aquaponics products. Results: The microbial ecosystem is essential for biological filtration of water through the mineralisation of nutrients required for plant growth in an integrated system. The aquaponics microbiome is complex, and bacterial composition varies between the different compartments of these systems. Establishing these bacterial ecosystems is essential for optimal functioning of aquaponics. At the phylum level, Proteobacteria and Bacteroidetes are dominant in aquaponics systems. Despite bacteria being fundamental to aquaponics, there are currently no reports of human pathogens in aquaponics products. Conclusion: Knowledge of the composition of bacterial populations in aquaponics systems will enhance understanding of relationships and functions within the microbiome. This in turn will allow for the establishment of sustainable and healthy aquaponics systems for food production.