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After years of development, the fish ponds in Yuncheng have formed a high-density breeding mode and common carp and grass carp are the main fish. This mode will make the water lack oxygen and deteriorate. The existing increasing-oxygen mode is limited to surface and local, slow speed in increasing oxygen and huge power consumption. At the power peak of production and living, it is easy to cause blackouts and influence the fishery production. In south china, some people used increasing oxygen technology with microporous pipeline at bottom in shrimp ponds and crab pools, which brought them good benefits.In 2009, in the Yellow River beach, we made a contrast between traditional impeller aerator and new type of underlying aerator. This experiment chose six 10 acres of high-density aquiculture fish ponds, dropped common carps, grass carps, spotted silver carps and silver carps, sampled respectively in March, April, June, July, August, September and November 5th. We compared the quality of water, planktonic algae and benefits. The quality of water includes temperature, pH, transparency, dissolved oxygen, ammonia nitrogen, nitrate nitrogen, nitrite nitrogen, phosphate, total phosphorus, potassium permanganate index and hydrogen sulphide.During the experiment, we have identified 75 species and varieties, which belong to 7 doors,24 families and 35 genera. The most is Chlorophyta, which is 7 families,16 genera,35 species and varieties. The second is Bacillariophyta, which is 7 families,9 genera,23 species and varieties. Again is Cyanobacteria and Euglenophyta, which are respective 5 families,5 genera, 10 species and varieties and 2 families,2 genera,4 species and varieties. Cryptomonas, Pyrroptata and Xanthophyta are all only 1 familiy,1 genus and 1 species.In all the year round, the Chlorophyta and Bacillariophyta are dominant in species and Chlorophyta is dominant in individuals of planktonic algae. The individuals is lowest for 0.1281×107/L and highest for 36.2032×107/L It is low in the first sampling and high in the late six samplings with less difference. There is not clear difference between the impeller aerator and underlying aerator in species and individuals of planktonic algae.Compared with the impeller aerator, the underlying aerator ponds are high in dissolved oxygen and low in ammonia nitrogen, nitrite nitrogen,hydrogen sulfide and potassium permanganate index, which reduce the incidence of disease and make fish live well in healthy environment. At the same time, it brings good economic and ecological benefits.Through our contrast test, fishermen know the advantages of the new technology. With the help of the government, underlying aerator will get very good promotion, at the same time, the fishery output of Shanxi Province will increase. This provides an effective way for developing resource-conserving fishery and laies a solid foundation for the sustained, healthy and stable development.
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