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In recent years, with the vigorous development of aquaculture industry, high-yield high-density breeding has had a rapidly increasing proportion; the pollution of aquaculture industry has become more and more serious. For restoratiing quaculture Water, ecological restoration techniques had emerged, one of which was floating bed of water eco-situ repair and control technology, and this technology was also concerned for its advantages.This paper choosed two kinds of aquatic economic plants-Ipomea aquatica and Oenanthe javanica,and one kind of aquatic plants- Eichhornia crassipes as selected plants,and took aquaculture effluent of ecological agriculture region of Shang hai Wu she as research object, used ecological floating bed technology to research purify effect and economic output of aquatic economic plants on-site static experiment, and also had a preliminary study about the effect of rhizosphere microorganisms. Besides, this paper had discussed a way of sustainable recycling economy which combined with the actual situation of agriculture region, the research show that:1. The static experiment of Ipomea aquatica, Oenanthe javanica and Eichhornia crassipes indicated that:all three kinds of aquatic plants can grow in the aquaculture wastewater, and the growth situation of Oenanthe javanica was significantly better than Ipomea aquatica, which also had a high economic output and more appropriate for the climate in Shanghai.In the static experiment for Ipomea aquatica, the average removal rate of TN, NH4+-N, NO3--N, NO2--N, TP, COD was 71.8%, 55.8%, 49.5%, 82.5%, 87.6%, 72.6%, for Oenanthe javanica, the average removal rate of TN, NH4+-N, NO3--N, NO2--N, TP, COD was 58.3%, 54.7%, 32.8%, 75.2%, 55.8%, 60.3%, for Eichhornia crassipes, the average removal rate of TN, NH4+-N, NO3--N, NO2--N, TP, COD was 76.5%, 48.3%, 77.5%, 100%, 85.9%, 93.4%. The three kinds of aquatic plants all had high removal efficiency for the aquaculture wastewater, and at the same time it explained that nitrogen and phosphorus had played a very important role during the growth of aquatic plants.2. This paper had researched the root system and adherent microorganisms of the three plants, which showed that:the root average growth rate of Ipomea aquatica and Oenanthe javanica were 174% and 92.4% in the static experiment, Ipomea aquatica was better than Oenanthe javanica. Take the methods of static experiment as reference, this paper choosed Ipomea aquatica as floating bed plant to build drainage channel demonstration project, it can be obtained direct economic gains 37628 yuan. The growth rate of Ammoniation bacteria, denitrifying bacteria, denitrifying bacteria for Ipomea aquatica and Oenanthe javanica of the static experiment were 2.5,2.0,3.7 and 1.5,1.5,2.0. The growth rate of Ammoniation bacteria, denitrifying bacteria, denitrifying bacteria for Eichhornia crassipes was 3.2,4.5,5.6, the number was much higher than two others, which because its developed root provided broad space for microbial adherent and rich microbes can dissolve organic compounds effectively.The study had proved this point very well., Eichhornia crassipes can effectively remove the organic pollutant to purify waste water which had higher content of nitrogen and phosphorus.3. In addition, this paper had discussed a way of sustainable recycling economy which combined with the actual situation of agriculture region, on the one hand, using the technology of aquatic economic plants bed to purify aquaculture wastewater and attained economic benefits, on the other hand, the harvest plants can be used to produce methane for the people daily life, and the biogas residue can be used to make fereilizer or feed regression farmland and raise shrimp farm, so that both realized harmless waste emissions and resources to achieve a secondary use, which had practical significance of sustainable development.
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