Modelling nutrient dynamics and waste valorisation in a fish-biofloc system

Samenvatting (Engelstalig)

The importance of aquaculture in satisfying global animal protein demand is increasing. Nevertheless, fed aquaculture practice is being criticised for its high nutrient emissions in cases with no or insufficient treatment of the discharged water. Application of biofloc technology is one of the promising solutions to reduce nutrient losses in aquaculture. In biofloc systems, the growth of different microorganisms in the culture system is maintained to ensure natural water treatment process. Despite the potential of biofloc systems, it is still difficult to manage a biofloc system due to the poor understanding of the dynamics between nutrients, food web, and cultured animals in the system.

In this thesis, experiments in a biofloc-Nile tilapia system in Indonesia are described together with the development of dynamic mathematical models using the experimental data. The models were used to simulate the nutrient dynamics and its relationship with fish and food web. Besides, the models were also used as a tool to provide management strategy insights given the complexity of a biofloc system.