| Summary: | 碩士 === 國立臺灣海洋大學 === 水產養殖學系 === 101 === Continuous light using LED, T5 and Fluorescent in three similar experiments were conducted using water spinach (Ipomoea aquatica) and garlic chives (Allium tuberosum) (hydroponic) and guppy (Poecilia reticulata) and tilapia (Oreochromis niloticus).Wastewater from aquaculture in a prototype aquaponic system (AS) were used to find a suitable growth environment and to maximize the production of water spinach and garlic chives and reuse of water. The system consisted of a fish culture aquarium and hydroponic trough with combined biofilter. All the different lights were set in an indoor room at the same temperature. Each experiment evaluated the effects of continuous lights (LED, T5 and Fluorescent) on plants growth. Fish culture wastewater flowed by submersible pump and gravity from the fish culture component to the hydroponic component in the flood and drain experiment while the garlic chives grown in net pots supported by floating Styrofoam in another experiment were floated in the aquaculture tank. In experiment one, two-weeks (5 cm long) cutting stem of water spinach were transplanted in each flood and drain hydroponic grow bed. The shoot length and number of leaves were recorded weekly for four weeks. Water quality parameters (Total Ammonia Nitrogen, Nitrite, Nitrate, pH, DO and Conductivity) were also recorded weekly. At the end of the four weeks, the fresh and dry masses (shoot and root) of each seedling were recorded as well as the root length. The treatment with LED recorded the most favorable plant growth (shoot length and number of leaves) as well as fresh and dry (shoot and root) masses. Plant shoot length in LED was 16% and 22% higher than T5 and Fluorescent lights and number of leaves 5% and 20% respectively. There were no significant differences in all water quality parameters except conductivity. Conductivity was higher under LED light treatment and positively correlated with shoot length and number of leaves. The latter two were also positively correlated. In experiment two, seedlings of garlic chives were grown in small net pot (8 per pot) and transplanted on floating raft Styrofoam floated in the aquaculture tank. The shoot length and water quality parameters were recorded weekly. At the end of the four weeks, the fresh and dry masses of the seedlings were recorded as well as the roots length.LED light treatment recorded the most favorable shoot length as well as fresh and dry (root and shoot) masses. Plant shoot length in LED was 15% and 18% higher than T5 and Fluorescent lights, respectively. Experiment three uses garlic chives and Nile tilapia in a floating raft aquaponic. The shoot length and water quality parameters were measured weekly. Plant shoot length in LED was 9 % and 15 % higher than T5 and Fluorescent lights, respectively. These similar results indicated that LED light could increase the growth of water spinach and garlic chives in an aquaponic system.
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