Distribution of Fungi in a Waste-Stabilization Pond System

Fungus populations in a small waste—stabilization pond system near Lebanon, Ohio, were determined using a number of plating and enrichment culture techniques. Throughout the system, and in an adjacent stream, 212 species of filamentous fungi and yeasts were recovered. Before the system was placed in operation, few filamentous fungi and no yeasts were recovered from samples of bare soil, while after a year's operation, numbers of species increased fivefold and numbers of colonies counted increased nearly 200—fold. Additional numbers of yeasts and filamentous fungi in pond waters and sludges were present but were not sampled quantitatively. Except for November, when adverse conditions of undetermined nature reduced the fungal populations, the numbers of viable cells recovered indicate a favorable habitat for fungi. It appears certain that fungi can be counted among those saprobic organisms that play a part in the degradation and thus the removal of organic wastes from the waters of waste—stabilization ponds...