Influence mechanisms of macro‐infrastructure on micro‐environments in the recirculating aquaculture system and biofloc technology system

Abstract

AbstractAquaculture intensification has emerged as a potential sustainable aquaculture strategy to contribute to the Food and Agriculture Organisation's United Nations Sustainable Development Goals associated with food security. Recirculating aquaculture systems (RASs) and biofloc technology systems (BFTs) are typical land‐based intensive aquaculture facility models that have been widely researched and applied. The rapid growth of both systems has boosted human nutrition and the regional economy but has also caused concerns about animal welfare, ecological protection, water treatment effectiveness and public health. One of the key links between aquaculture and ecological issues is the treatment of harmful particulates in wastewater, particularly organic metabolic microparticles. These microparticles are derived from decomposition waste feed, faeces and biofilm and provide a surface for bacterial growth and proliferation. The increase in microparticle abundance can directly affect bacterial activity and abundance and adversely affect the environment. Furthermore, the decomposition and motion of these particles are related to the mechanical stress caused by the water flow pattern in aquaculture tanks. The internal configurations of the tank can control the hydrodynamic characteristics, such as the water velocity, uniformity, pressure and turbulence in aquaculture tanks, and thus influence the morphology of particles. This review analyses and discusses how macro‐infrastructure influences the microenvironment in aquaculture tanks. These results provide a theoretical foundation and practical implications for improving the performance of aquaculture systems and environmental management in intensive aquaculture. It is concluded that optimisation of infrastructure design is key to improving the water flow patterns and self‐cleaning performance of tanks and achieving high efficiency of RASs and BFTs, and is critical for the fulfilment of the Sustainable Development Goals in aquaculture.