Preliminary Study On The Effect Of Microbial Agents On The Purification Of Aquaculture Water

Since the twenty-first Century,China's inland aquaculture industry has a rapid development.High density intensive culture mode has brought great culture output,but also because of deposition of aquaculture water excertion,bait and the accumulation of biological debris,causing the ammiona,nitrite concent increased.It not only reduced the production of breading,but also might break the balance of micro ecological aquaculture.Biological method with the characteristics of the high efficency,environment protection,low cost,no two pollution has been widely used.Microbial prepation can convert the toxic ammiona,nitrite into the harmless nitrate so as to play a role in purifying water quality.Therefore,to explore the different strains,different doses of nicrobial prepation and the filter media which can make the nitrifying bacteria for the rapid attachment and growth has signifance to the aquaculture.In this study,we will add nitrifying bacteria,bacillus,the compound agent into the culture system,and loading sediment,nitration ball based on the device.It can explore the degradation effect of diffferent treatments on the amminia nitrogen and nitrite in the auqaculture water.The following conclusions are obtained through the study:(1)Nitrifying bacteria,bacillus and the compound agent was added into shrimp aquaculture system under the condition of 25?,pH7.5,DO6mg/L.After 30 days of culture,the results showed that the removal efficiency of ammonia nitrogen:the nitrobacteria+bacillus group>the nitrobacteria group>bacillus group>the blank group;Nitrite removal effect:the nitrobacteria+bacillus group>the bacillus group>the nitrobacteria group>the blank group;the average weight of the nitrobacteria+bacillus group in shrimp increased the most,the nitrobacteria group is slightly higher than the bacillus group,the blank group at least.(2)Nitrification bacteria preparation and two times of bacteria preparation were added into shrimp aquaculture system under the condition of 25?,pH7.5,DO6mg/L.After 30 days of culture,the results showed that the removal efficiency of ammonia nitrogen:two times nitrobacteria>the nitrobacteria group>the blank group;Nitrite removal effect:two times nitrobacteria group>the nitrobacteria group>the blank group,but the removal efficiency of the two times nitrobacteria group was not a multiple relationship with the nitrobacteria group;the average weight of two times of nitrifying bacteria group in shrimp increased the most,the nitrobacteria group next,the blank group at least.(3)The nitrobacteria and bottom sediment group,the nitrobacteria group,the bottom sediment group,the blank group were set up under the condition of 25?,pH7.5,DO6mg/L.After 30 days of culture,the results showed that the removal efficiency of ammonia nitrogen:the nitrobacteria group and bottom sediment group>the nitrobacteria group>the bottom sediment group>the blank group;Nitrite removal effect: the nitrobacteria group and bottom sediment group>the nitrobacteria group>the bottom sediment group>the blank group;the average weight of the nitrobacteria and bottom sediment group increased the most,the nitrobacteria group is slightly higher than the bottom sediment group,the blank group at least.(4)The nitrobacteria and nitration ball group,the nitrobacteria group,the blank group were set up under the condition of 25?,pH7.5,DO6mg/L.After 30 days of culture,the results showed that the removal efficiency of ammonia nitrogen:the nitrobacteria and nitration ball group>the nitrobacteria group>the blank group;Nitrite removal effect:the nitrobacteria and nitration ball group>the nitrobacteria group>the blank group;the average weight of the nitrobacteria and nitration ball group in shrimp increased the most,the nitrobacteria group next,the blank group at least.(5)The dominant bacteria of the nitrobacteria group were Phaeodactylibacter and Donghicola,the proportions were 13.690 % and 13.229 %,which were the main distribution of bacteria;next for Tenacibaculum and Planctomyces,the proportions were 9.804% and 7.103%.The dominant bacteria of the nitrobacteria and nitration ball group was Phaeodactylibacter,the proportions was more than 70%;others for Psychroflexus and Maritimibacter,the proportions were 2.894% and 2.092%.Both major strains exist Phaeodactylibacter·xiamenensis and Phaeodactylibacter·luteus.