复合微生态制剂对池塘水体氮循环细菌动态变化的影响

采用最大可能数法分析了不同季节池塘水体中氨化细菌、亚硝化细菌、硝化细菌和反硝化细菌的种群数量。结果显示,在池塘水体中,各种氮循环细菌的分布规律为:氨化细菌的n(MPN)为春季(8.6×105)>夏季(6.8×105)>秋季(3.1×104);亚硝化细菌为夏季(3.2×105)>春季(6.4×103)>秋季(1.8×103);硝化细菌则正好相反,为春季(2.4×106)>秋季(1.0×106)>夏季(7.6×105);反硝化细菌为春季(4.5×106)>夏季(9.5×105)>秋季(6.2×104),由春季到秋季逐级降低1个数量级。养鱼的池塘水体中氮循环细菌的分布与不养鱼池塘是相类似的,惟一有所不同的是各种细菌的含量略为高一些。使用活菌数为2×108CFU·mL-1的含枯草芽孢杆菌(Bacillussubtilis)、施氏假单胞菌(Pseudomonasstutzeri)、水生假丝酵母(Candidaaquati-ca)和球形酵母(Saccharomycesglobosus)的复合微生态制剂后,可明显提高池塘水体中氨化细菌、反硝化细菌和亚硝化细菌的数量,但对硝化细菌的影响不大。复合微生态制剂可使池塘水体各种氮循环细菌在春夏秋不同的季节保持较为恒定的数量,最大限度地提高氮循环的速率和效能。试验同时发现氨化细菌、反硝化细菌的数量与其相应作用的产气量呈显著的相关性(P<0.01),说明两者可将水体中的氮素转化为NH3、N2O或N2等不同的气体而从水中逸散。研究结果表明,复合微生态制剂通过直接影响水体中氮循环细菌的数量而促进水体的氮循环。

Effects of Compound Microbes Preparation on Variety of Nitrogen-Cycle Bacteria in Pond Water

Most probable number (MPN) method was employed to determine distribution of the nitrogen-cycle bacteria in a pond water, including ammonifying bacteria, denitrifying bacteria, nitrosobacteria and nitrobacteria. The results showed that the n (MPN) of ammonifying bacteria or denitrifying bacteria in the pond water was most in spring and least in autumn, while the number in summer was in middle. The n (MPN) of nitrosobacteria in summer was more than in spring and autumn. While the n (MPN) of nitrobacteria was most in spring, least in summer. The kind and distribution of nitrogen-cycle bacteria in the fishery pond water was similar to the un-fishery pond water,while the n( MPN) was more. After treatment by the compound microorganism preparation which contained Bacillus subtilis ,Pseudomonas stutzeri, Candida aquatica and Saccharomyces globosus, the n (MPN) of ammonifying bacteria, denitrifying bacteria and nitrosobacteria obviously increased, but the number of nitrobacteria had no change. The results indicated that the compound microorganism preparation could cause the nitrogen-cycle of water to keep balance in the different seasons, and rapidly raised the effect and speed of the nitrogen-cycle. The study also showed the n (MPN) of ammonifying bacteria and denitrifying bacteria had significantly correlation with the gas volume (P<0.01). The ammonifying bacteria and denitrifying bacteria could convert organic nitrogen and nitrite into gas nitrogen (NH3,N2O,N2). The results showed that the compound microorganism preparation could affect the number of the nitrogen-cycle bacteria in the pond water and had influence on nitrogen-cycle.