Qualidade da água e dos efluentes em viveiros de reprodução de Astyanax lacustris (Reinhardt, 1874) na Estação de Piscicultura de Paulo Afonso - BA

Abstract

Water and food are the main inputs in semi-intensive and intensive aquaculture. With increasing biomass, increases the food supply, nutrients and other substances that may compromise the water quality and producing effluents that can impact the receiving water body. The Fish Culture Station of Paulo Afonso has the condition of the Operating License to deploy a monitoring plan for its effluents. It also needs to attend to the granting of water availability and sewage discharge. Thus, the present work support the preparation of the Effluent Monitoring Plan of the Fish Culture Station of Paulo Afonso. The objective of the present study was to evaluate the water quality along the growing period and of effluents during draining and harvest in ponds of Astyanax lacustris (Reinhardt, 1874). Three contiguous ponds of 2000 m2 each were fertilized with cattle manure and supplied with water from the Moxotó reservoir. Water quality was evaluated during the supply and fortnightly at different depths. After nursery period (64±1 days), ponds were drained for the harvest of fingerlings, during which the quality of effluents was evaluated at every 25 cm of pond water level lowering. During culture period, pond water quality variables were within acceptable standards for the cultivation of tropical aquatic organisms, and no significant differences among depths were detected. However, significant differences were found among fortnights and ponds. With regard to effluent quality, it differed among ponds, but not among depths during draining. The effluents from the production of A. lacustris in EPPA are unsuitable to environmental standards for release in natural aquatic environments, with regard to phosphate forms, chlorophyll a and pH.