Studies Of The Technology Of Water Quality Control In Semi-enclosed Ecological Marine Culture Pond

The research was aim to establish three aquaculture models which implemented water quality control in semi–closed ecological pond aquaculture according to different aquaculture methods,piscina bottom quality and water quality situation of Qinhangdao, Tangshan and Cangzhou and had got some conclusiongs as follws:1.The research and experiment on water quality control of semi–closed ecological pond aquaculture in QinhangdaoDuring July 22 to September 22, 2009 there was being a experiment on water quality control in semi–closed ecological pond in Qinhuangdao Jiangpeng aquaculture company. According to different piscina bottom quality, water quality and aquaculture methods we had established two kinds of aquaculture patterns in two experiment ponds No 2 and No3 as bellow: Adopt Fugu rubripes and Penaeus (Marsupenaeus) japonicus mix-culturing in pond 2 as test ponds, Adopt Fugu rubripes and Penaeus (Marsupenaeus) japonicus and Sinonovacula constricat canarck mix-culturing in pond 3 as test ponds, adopt Fugu rubripes and Penaeus (Marsupenaeus) japonicus mix-culturing in pond 1 as control pond. Stocking amount: Fugu rubripes 88ind/667m2, Penaeus (Marsupenaeus) japonicus 3500ind/667m2 firstly, 4000ind/667m2 secondly. During aquaculture times, we exchange 5% volume of water every 10d in pond 2 and apply compound microecological preparation after accentuate, as the same time we exchange 20% volume of water in the control pond without compound microecological preparation. The results indicated that dissolved oxygen has varying degree enhancement in the test pond of mix-cultur Sinonovacula constricat canarck or apply compound microecology preparation. In descending order of pond 2, Pond 3 ,pond 1. Ammonia nitrogen, nitrite nitrogen and chemical oxygen demand in the test pond, compared with comparison pond also have reduce. The growth survive, length and weight of Penaeus (Marsupenaeus) japonicus in the test pond, compared with control pond also have raised.Mix-cultur Sinonovacula constricat canarck or apply compound microecology preparation not only purifying water quality but also improving survive of Penaeus (Marsupenaeus) japonicus.2. The research and experiment on water quality control of semi–closed ecological pond aquaculture in Tangshan.During July 14 to October 2, 2009 there was being a experiment on water quality control in semi–closed ecological pond in Tangshan Puli choice rare sea food aquaculture limited corporation. According to different piscina bottom quality, water quality and aquaculture methods we had established two kinds of aquaculture patterns as bellow: Adopt Fugu rubripes and Fenneropenaeus chinensis mix-culturing in pond 2 as test ponds and apply compound microecology preparation at the same time, pond 1 and pond 2 as control ponds. Stocking amount: Fugu rubripes 60ind/667m2, Fenneropenaeus chinensis 2250ind/667m2. During aquaculture times, we exchanged 5% volume of water every 10d in pond 2 and apply compound microecological preparation 0.45g/m3, exchanged 20% volume of water every 10d in control ponds without compound microecological preparation. The results indicated that dissolved oxygen and nitrate in the test ponds increased by 20.9% and 31.1%; The nitrogen, the ammonia nitrogen, the chemical oxygen demand and the inorganic phosphorus decreased by 30.1%, 29.0%, 20.6% and 41.9%. Phytoplankton densities were lower in prophase and dominant species was diatom but it increased rapidly in metaphase and reached a maximum in anaphase, and always at the high state in test pond, the maximum value is 5.09 times as much as pond 1 and 7.14 times as much as pond 3; Zooplankton densities were lower in prophase ,increased rapidly in metaphase and reached a maximum in anaphase, and always at the high state in test pond, too. The maximum value is 8.21 times pond 1 and 3.37 times as much as pond 3. The density changing trend was similar between zooplankton and phytoplankton, and the maximum of zooplankton densities appears after the maximum of phytoplankton densities. Changes from the plankton species number and community composition looked that, the test pond better than control ponds.3. The research and experiment on water quality control of semi–closed ecological pond aquaculture in Huanghua.During July 22 to September 22, 2009 there was being a experiment on water quality control in semi–closed ecological pond in Huanghua xinhai biotechnology limited corporation. According to different piscina bottom quality, water quality and aquaculture methods we had established an aquaculture patterns as bellow: Adopt Scylla serrata (Forskal) and Fenneropenaus chinensis named"Yellow Sea 1"mix-culturing. Stocking amount: Fenneropenaus chinensis named"Yellow Sea 1"3500ind/667m2, Scylla serrata (Forskal) 300ind/667m2. During aquaculture times, we exchanged 5% volume of water every 10d in pond 1 and pond 2 , appled compound microecological preparation 0.45g/m3, exchanged 20% volume of water every 10d in control ponds without compound microecological preparation. The results indicated that in aquaculture period the ammonia nitrogen, the chemical oxygen demand and the alkalinity decreased by 26.1%, 9.2% and 22.0%; pH value have Little change in test ponds and control ponds, Basically maintained between 8.4～8.9. The growth survive, length or weight of Scylla serrata (Forskal) and Fenneropenaus chinensis named"Yellow Sea 1"in test ponds have distinct raising in test ponds. The growth survive increased by 20.0% and 16.4%; The length or weight of Fenneropenaus chinensis named"Yellow Sea 1"increased by 8.1% and 14.1%; The weight of Scylla serrata (Forskal) increased by 4.0%.