Quality of effluent of pisciculture treated by aerobic and anaerobic biological filters to be used in irrigation

Abstract

Fish farming depends on environmental products and services for their sustainability, such as effluent and waste dilution capacity and availability of good quality water. The environmental problems related to the practice of this activity have to do with the water quality of effluents from fishponds that have organic matter, suspended solids and high concentrations of nutrients. Therefore, the objective of the present study was to analyze the quality of pisciculture effluents treated by two biological filters for release or use in agriculture. The experiment was conducted at the IFGoiano, Rio Verde campus, where two fish farming systems were built, with two different biological filters, the aerobic gravel filter (FB) and the anaerobic bamboo filter (FA), where collections were made at the exit of each one to verify the effluent quality for release and / or irrigation purposes. A completely randomized experimental design was used, in a 2×4 split-plot arrangement, and with three replications. The treatments consisted of four collection times, after the implementation of the experiment (60, 70, 80, and 90 DAI) and two filter types (anaerobic bamboo filter; and aerobic stone filter). The quality of the treated effluent was analyzed in the laboratories of Hydraulic and Irrigation; Sanitation and Environment; and Water and Effluents of the GFI-RV. The parameters evaluated were: electrical conductivity, total dissolved solids, pH, turbidity, alkalinity, chemical oxygen demand (COD), dissolved oxygen (DO), and biochemical oxygen demand (BOD). The parameters pH, total dissolve solids, turbidity, DO, and BOD were in accordance with the standards established by the CONAMA 357/05 for Class II waters (allowing use for irrigation of vegetables and fruit plants).