在这些实验中，三个完全混合的生物膜反应器以1.5或2.5 mg/L的恒定浓度注入氨氮（NH4+-N）。在0至10 mg C/L的浓度范围内向进料介质中添加醋酸盐。醋酸盐负荷的突然增加导致硝化效率的暂时恶化和亚硝酸盐氮（NO2--N）的形成。不完全硝化是由于异养细菌的突然高生长率而发生的，异养细菌的生长速度超过了硝化细菌，并暂时将其从生物膜中清除。异养细菌新的稳定状态的建立，使硝化菌在生物膜中再生，实现近100%的硝化。这些结果表明，可生物降解有机物输入负荷的波动会通过fast的竞争对硝化性能产生不利影响- 生长异养细菌，但长期稳定硝化是可能的。包括11个参考文献、表格、图表。

In these experiments, three completely mixed biofilm reactors were fed ammonium nitrogen (NH4+-N) at a constant concentration of 1.5 or 2.5 mg/L. Acetate was added to the feed media at concentrations ranging from 0 to 10 mg C/L. Sudden increases in the acetate loading led to temporary deterioration of the nitrification efficiency and to formation of nitrite nitrogen (NO2--N). The incomplete nitrification occurred because of the suddenly high growth rate of the heterotrophic bacteria, which outgrew the nitrifiers and temporarily swept them out of the biofilm. Establishment of a new steady state for the heterotrophic bacteria allowed the nitrifiers to regrow in the biofilm and achieve nearly 100 percent nitrification. These results demonstrate that fluctuations in the input loading of biodegradable organic matter can adversely affect nitrification performance through competition by fast-growing heterotrophic bacteria but that long-term stable nitrification is possible. Includes 11 references, tables, figures.