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In this study, water spinach Floating Bed Technology preliminary used in pond culture, aimed at improving the ecological environment of aquaculture water, conservation of water resources and to reduce the impact of farming activities on the surrounding environment for China's aquaculture industry efficient, high-quality, sustainable development reference. The main findings are as follows: 1. Screening water spinach varieties suitable for the growth of pond water environment. The use of a floating bed system, A Comparative Study of the growth characteristics of the varieties (large Yeqing Terrier, Egeria Qinggeng, big-leaf White Terrier, willow White Terrier) in eutrophic ponds in central China four common water spinach (Ipomoea aquatica Forsskal) water nitrogen and phosphorus removal capacity. The results show that: the large leaves White Terrier in biomass accumulation rate, growth potential, growth cycle significantly better than the other three varieties; Yeqing stems and large leaves, white stems Ipomoea various forms of nitrogen, phosphorus removal rate cumulative removal of ammonia, nitrate, total nitrogen, phosphate and total phosphorus 15d 79.35-91.39% ,84.38-85 .32% ,62.30-68 .98% ,70.09-85 .26% and 77.95-78.88% respectively. Comprehensive comparison, big-leaf Terriers water spinach the best floating bed material in four varieties, can be widely used in the repair of ponds and other eutrophic water body. Set different coverage (2.5%, 5%, 7.5%). Fry fish pond water spinach floating bed, looked at the effects of of Ipomoea floating bed in aquaculture ponds. The results showed that: the the water spinach biomass per unit area up 12.63kg/m2; floating bed control pond water phosphorus (P043-TP) concentration and improve the water transparency effects significantly increase the effect of enhanced coverage and with the floating bed; Ipomoea developed root system provide good habitat and feeding places for fish the grass carp (Ctenopharyngodon idellus), fish (Carassius auratus) the the bream (Parabramis pekinensis,), bighead carp (Arixtichthys nobilis) develop specifications greater than traditional aquaculture ponds, improve fish pond total output and economic benefits, coverage pond of the best group of 5.0% compared to the traditional pond fish production 59.1kg/mu, acres of high-profit 685.3 yuan. Ipomoea floating bed insufficient to reduce the level of dissolved oxygen in the water, remove the water nitrogen (NH4, NO2-, TN) ineffective, the impact of the growth of silver carp (Hypophthalmichthys molitrix), applications need to pay attention to the use of the appropriate supporting technology measures. Set different density at the surface of the pond water spinach, water spinach in crucian carp monoculture ponds. The results showed that: ① polyculture pool crucian carp fish dishes daily gain, survival rate, feed conversion and growth indicators monoculture group difference was not significant (P lt; 0.05), Ipomoea not affect the growth of crucian carp; ② During the experiment, the of fish dishes polyculture group ammonia water, non-ionic ammonia, total nitrogen, phosphate, total phosphorus average concentration was significantly lower than the monoculture crucian carp group, transparency polyculture was significantly higher than monoculture, DO, pH is significantly lower than the monoculture, cluster analysis showed that 1000 g · m-2 of water spinach dish set of water quality is best, followed by 500 g · m-2 group, the worst 0g · m-2 and 250 g · m-2 group. Ipomoea has a strong farming water purification, and strengthening with the purifying effect of the increase in biomass; ③ water spinach substantial absorption of water nitrogen and phosphorus, a the polyculture group feed nitrogen, phosphorus utilization, nitrogen highest phosphorus utilization 1000 g · m-2 water spinach group monoculture 2.19 times and 3.75 times respectively. Dishes: fish and nitrogen, phosphorus utilization quadratic regression equation was found that the system best dish: fish stocking ratio 1.62-1.85:1.
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