| Summary: | 碩士 === 朝陽科技大學 === 環境工程與管理系碩士班 === 98 === Maintain a good pond fish culture environment is crucial for growing healthy fish to achieving satisfactory production for improving culture efficiency. It depends on the water quality conditioning and culture environment such as pond sediment properties. In this study sediments were collected from Shih-Ban fish, shrimp and Wu fish culture fishery ponds in southern part of Taiwan to investigate the effect of water quality and sediment environment of fishery ponds by adding fulvic acids (FA) extracted from peat composite material or activated carbon (AC) or δ-MnO2. The experiments were carried out by amendment 5% (w/w) of FA or AC or δ-MnO2 to the sediments and as well as control groups without adding of FA or AC or δ-MnO2. The treated sediments and controls were subjected to repeatedly dried–wetted cycle for four times to simulate the in situ environmental condition. All the experiments were performed in transparent plastic made fisher box (27.0 ×16.9×11.7 cm) containing 2 L of sea water and filled with 500 mg air-dried sediment with and without amendment of FA or AC or δ-MnO2 at four replicates. Each fishery box with the sea water from fishery pond was purged with air in a flow rate of 700 −750 mL min−1 and baby white-shrimps or fish were cultured as like in fishery ponds. The results showed that the amended FA to the sediments increases the concentrations of dissolved organic carbon (DOC), macro-elements (Ca, Mg, K and Na), micro-elements (B, Cu, and Mn) and chlorophyll A and all of these in simulated fisher ponds were observed much higher concentrations than those of control groups. Also, the daily monitoring aspects pH, specific electrical conductivity (EC), and salinity of the simulated fishery pond water showed that EC and especially salinity of pond water show higher values amended with FA than that corresponding to the control groups. However, the amendment of AC to the sediment, initially it adsorbs pollutants in the simulated fishery ponds and controlled the all water quality parameters and sediment environment. Adsorption of pollutants by the activated carbon reached saturation stage resulting in gradual deterioration water quality and sediment environment. Although, δ-MnO2 was amended to the simulated pond sediment it can strongly oxidized the pollutants and resulting control the all water quality parameters and sediment environment within the limits of biological tolerance for growing healthy fish or shrimp to achieving satisfactory production.
|
|---|
