A model for food nutrient dynamics of semi-intensive pond fish culture

A dynamic model was developed to explain food nutrient dynamics in a semi-intensive aquaculture pond and to determine food nutrient requirements for supplementary feeds for Nile tilapia. The model links food nutrient production with elementary nutrient dynamics and fish growth by including four sectors: food nutrients, fish growth, elementary nutrients, and dissolved oxygen. The model, developed by using stella ii software, simulated a field experiment that was designed to determine limiting nutritional factors for fish growth in fertilized ponds. Simulation results show that supplementary feeding compensates for natural food nutrient deficiencies. Results also reveal that protein supplements are necessary for increasing fish yields of fertilized ponds. Comparison of the data from simulation and observation indicates that the simulation values have a close correspondence with observed data, and the model is able to capture essential food nutrient dynamics in semi-intensive aquaculture ponds.