Artificial floating islands as a tool for the water quality improvement of fishponds

In this study, the ecotechnology artificial floating islands (AFIs), colonized by Eichhornia crassipes, have been tested as a tool for water quality improvement of fishponds. The experiment was carried out in semi-intensive production during grow-out period Nile tilapia, comprising one cycle. It completely randomized with two treatments (with and without AFIs) three replications. Temperature, dissolved oxygen, conductivity, pH, turbidity, total solids (TDS), transparency (Secchi) concentrations chlorophyll (CL a), nitrogen (TN), ammonia (TAN), phosphorus (TP) orthophosphate (PO43--P) were analyzed fortnightly Two groups ordered based on environmental characteristics formed applying Principal Component Analysis (70.68% explicability). fishponds AFIs assigned to higher values Secchi lower TDS nutrients. On other hand, highest these variables, except Secchi. 30 days, showed lowest TP PO43--P, CL a, TN TAN, differences recorded after 90 days. use has demonstrated potential conserve fishponds, notably biologically assimilable elements (PO43--P TAN) those directly related eutrophication (P N). Artificial should be encouraged small medium-sized farmers improve However, new coverage rates must evaluated, well control hydraulic retention rates.
 Keywords: aquaculture, ecotechnology, free-floating aquatic macrophytes.