Cage aquaculture uses the dilution potential of water bodies to assimilate nutrients discharged from cultured fish . Maintaining the physical , chemical , and biological integrity of the water necessitates nutrient emissions to be compatible with the ecosystem’s assimilative capacity.
Calculating ecological carrying capacity in large hydroelectric reservoirs employs mass balance models , primarily addressing phosphorus as the key contributor to eutrophication . This study aims to estimate the environmental carrying capacity of an reservoir stretch for nile tilapia grow -out cage aquaculture , contrasting modeling projections with field data. Focused on the Chavantes reservoir in the midstream of the Paranapanema River, in Southeastern Brazil , the study conducted four limnological surveys , evaluating temperature , conductivity , turbidity , pH, total nitrogen , total phosphorus , and chlorophyll-a.
Additionally , bathymetric analysis and water flow data of the study area informed environmental carrying capacity calculations based on phosphorus levels . Utilizing the same model , theoretical tilapia farming impacts on water phosphorus levels were determined using production data. Regression analysis compared model-predicted total phosphorus values with field records . Results indicate the farm’s compatibility with the site’s environmental carrying capacity . Strong concordance between predicted and observed water phosphorus concentrations downstream of the farm (r = 0.95; P = 0.048) support the reliability and accuracy of Dillon & Rigler’s mass balance model in estimating environmental carrying capacity in hydroelectric reservoirs.