Studies on Microbiotic Cycles in Surface Waters

Abstract

This article discusses microbiotic cycles as they may directly and indirectly contribute to the tastes and odors in water supplies in the southwestern and south central parts of the United States. The basic role of algae is discussed, along with seasonal cycles of algae, the effects of algal degradation, the rise of gram‐negative bacteria, diatoms and blue‐green algae, algae‐bacilli relationship, actinomycete development, and effect of pollution. This data substantiates the hypothesis that microbiotic cycles are interdependent in such a way that the nutrients originally derived from the autotrophic forms are responsible for the production of the various types of bacteria in the sequences in which they develop in water supplies. It is noteworthy that the blue‐green algae appear to be the best sources of nutrition for both the gram‐negative heterotrophic bacilli and the actinomycetes, whereas the remains of the blue‐green algae and the actinomycetes appear to be the stimulating factor for the growth of the gram‐positive spore‐forming bacilli.