Microbial biofilm development was followed under growth conditions similar to those of a projected salinity power plant. Microscope glass cover slips were piled in biofilm reactors to imitate the membrane stacks in such a plant. A staining technique closely correlating absorbance values with biofilm dry weight was used for the study. Generally, the biofilms consisted of solitary and filamentous bacteria which were evenly distributed with considerable amounts of various protozoa and entrapped debris of organic origin. Protozoa predation was shown to decrease the amount of biofilm produced. The biofilm development lag phase was longer at lower temperatures. The subsequent growth phase was approximately arithmetic until stationary phase appeared. Adaptation of a hyperbolic saturation function gave curves that agreed well with the logarithm of the amount of biofilm as a function of time. Increased flow velocity, temperature, and nutrient concentration increased the biofilm production rate. An exponential relationship was shown between biofilm production rate and flow velocity within the range of 0 to 15 cm s−1. Intervals in which the biofilms were exposed to fresh water decreased the biofilm production rate more than four times. If the cover slips were inoculated with untreated seawater for 24 h, subsequent UV treatment had an insignificant effect on the biofilm formation.
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机译：在与预计的盐度发电厂相似的生长条件下，进行微生物生物膜的发育。将显微镜玻璃盖玻片堆放在生物膜反应器中，以模仿这种工厂中的膜堆。这项研究使用了一种将吸光度值与生物膜干重紧密相关的染色技术。通常，生物膜由孤立的和丝状的细菌组成，它们均匀地分布着大量的各种原生动物和被有机物捕获的碎片。原生动物的捕食被证明可以减少生物膜的产生。生物膜发育滞后阶段在较低温度下更长。随后的生长阶段近似算术，直到出现稳定阶段。双曲饱和度函数的适应给出的曲线与生物膜数量随时间的对数吻合得很好。流速，温度和养分浓度的增加增加了生物膜的产生速率。结果表明，在0〜15 cm s -1 范围内，生物膜的产生速率与流速呈指数关系。生物膜暴露于淡水的间隔使生物膜生产率降低了四倍以上。如果将盖玻片用未经处理的海水接种24小时，则随后的紫外线处理对生物膜的形成影响不明显。
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