Study On Effect Of Photosynthetic Bacteria (PSB) On Ecological Environment In Large Aquatic Water

Aquaculture is the fastest growing food-producing sector in the world because the global population is increasing, thus, the demand for aquatic food products is also increasing. The ammonia and nitrite concentration is much more than standard in aquatic pond, because of high farming density, much feeding and releasing of breeding, industrial, Agricultural waste water to the pond. It will lead to severely overweight of chemical factor and growth of bad bacteria in aquatic water, constitution declining of fish and shrimp, bad ability of anti-stress, easy affects of baeteria, and then disease will break out in aquatic animal especially in the large aquatic water, water bodies have more complex environment, water quality regulation is more difficulty and higher cost in administration than smaller water bodies. Photo Synthetic Bacteria, PSB, is of interest as a microbial agent with the characters such as nature, innocuity, no side-effeet, no pollution, no residue and safty.Photosynthetic bacterial is one of the widely existed and ancient bacterial population, it is prokaryote that possess the orginal photosynthetic system which enable the photosynthesis under anaerobic conditions. Photosynthetic bacterial, as one of the widely used watar Purification preparation, is able to utilize many kinds of organic matter for metabolism and growth under aeroboic microaerobic and anaerobic conditions.it is dominant in the purification of water quality and the development of fish and shrimp. The enviornrnental effeet is prominent. So far, the application of PSB in the small aquaculture water is more than n the large aquatic water.In addition, the effectiveness of the use of PSB is vary In different regions by PSB as a result of environmental factors influenced. However, little is known regarding application of PSB in the large aquatic water in northern china. Two large aquatic waters in the LiaoNing Province were chosen for this experiment. One was experiment and another was control. In the experimental condition, the photosyntheticbacteria(PSB) was isolated,enriched and cultured. After reproducing the PSB with the water of well. PSB was sprinked to the experimental large aquatic waters, then the hydrochemistry index, plankton biomass,the growth of Carp, Grass carp, Silver carp and Bighead carp was investigated in the large aquatic waters.The results show that PSB had obvious effect on hydrochemistry index in the large aquatic water in northern china. SD, sulfide, nitrate-N and COD of the experimental aquatic water are lower than those of control aquatic water after sprinking PSB. The indexes decreased geatly in the experimental aquatic water but did not change very obviously in the control aquatic water. However, the COD in the experimental aquatic water did not reduced greatly and had no significant difference with that of control aquatic water. On the other hand, DO, ALK, T.H in the experimental aquatic water are higher than those of control group and changed obviously. but they did not change very obviously in the control aquatic water.PSB can effect the plankton biomass in the large aquatic waters.the phytoplankton of experimental large aquatic waters increased notably after applicating PSB. It also can make the algaes unfitable for fish decrease. On the other hand, the zooplankton biomass is higher than that of the control large aquatic waters. The phytoplankton and zooplankton biomass changes marginally to the control large aquatic waters in two years.PSB can effect the growh of Carp, Grass carp, Silver carp and Bighead carp. the weight gain in a day and surviving percentage of fish in the experimental large aquatic waters changed significantly. the two indexes in the experimental large aquatic waters increased at some degree. The reason may be that PSB change the water quality well, Enhance the fish body immunity and increase the plankton which provided the fish good environment and enough food. But the weight gain in a day and surviving percentage of fish in the control large aquatic waters changed littlely. The results demonstrated that the PSB play an important role that it can Increase the aquatic production and improve the aquatic efficiency by Improving water quality, weight gain in a day and surviving percentage of fish in the large aquatic water in northern china.This study has an important practical value for fish production and has an important Reference value for Ecological Environment in the large aquatic water in northern china.