摘要：为探讨枯草芽孢杆菌（Bacillus subtilis）在鱼类养殖池塘中的生态作用，采用直接往养殖水体中投放该制剂的方法，研究分析微生物数量及其与环境因子的相关关系。试验结果显示，枯草芽孢杆菌，实验池数量为0.35×103~1.45×103 cfu/mL，对照池为0.04×103~0.08×103 cfu/mL；浮游植物生物量，实验池为0.094~1.521 mg/L，对照池为0.103~0.763 mg/L，实验池中枯草芽孢杆菌数量和浮游植物生物量均高于对照组。试验鱼塘中枯草芽孢杆菌与硅藻数量呈显著正相关，相关系数0.844（P<0.05）；当溶氧＞6 mg/L时, 枯草芽孢杆菌与亚硝酸盐氮含量呈显著负相关，相关系数－0.915（P<0.05）。溶氧过低（＜2 mg/L），枯草芽孢杆菌对亚硝酸盐氮、氨氮没有明显的降解作用；溶氧＞6 mg/L时对亚硝酸盐氮、氨氮的降解作用明显。研究表明，投放适量浓度的枯草芽孢杆菌能有效改善养殖水体状况，对水质起到进一步净化作用。
Effects of Bacillus subtilis on the ecological factors in marine fish pond
WANG yuexia1，YANG xiulan2，DU rongbin2，LIU liming2，LIUyihao1
(1 Shandong Marine Resource and Environment Research Institute,Yantai 264006,China;
2 School of Ocean,Yantai University, Yantai 264005, China)
Abstract: By artificially added micro-ecological agents of Bacillus subtilis, the relationship between microbe quantity and environmental factors was investigated in marine fish pond, to discuss the ecological effects of Bacillus subtilis on marine fish pond. The results showed that the Bacillus subtilis amounts 0.35~1.45×103 cfu/mL in the experiment group, 0.04~0.08×103 cfu/mL in the control group and the phytoplankton biomass (0.1026~0.7632 mg/L in the experiment group and 0.0936~1.5209 mg/L in the control group) were both significantly higher in the experiment group than those in the control group. In the experiment group, the Bacillus subtilis amounts were significantly positive correlative with the diatom abundance (the coefficient = 0.844, P<0.05), but those were significantly negative correlative with the nitrite nitrogen concentration (correlation coefficient = -0.915, p<0.05), if the dissolved oxygen concentration was more than 6 mg/L. In addition, if the dissolved oxygen concentration was too low (< 2 mg/L), Bacillus subtilis had no degradation of the ammonia nitrogen and the nitrite nitrogen in the seawater, but Bacillus subtilis had a significant degradation effects on the ammonia nitrogen and the nitrite nitrogen, when the dissolved oxygen concentration reached 6 mg/L or more. Thus it can be inferred that the appropriate concentration of Bacillus subtilis can effectively improve the condition of aquaculture water, and further purify the water quality.
Key words: Bacillus subtilis; Colony number; Dissolved oxygen; Marine fish pond; Ammonia nitrogen; Nitrite nitrogen