Investigations on the survival of fecal bacteria in experiments with and without sediment addition
Bauerfeind, S.; Gerhardt, G.G.; Rheinheimer, G.
Zentralblatt für Bakteriologie Mikrobiologie und Hygiene. 1. Abt. Originale B Hygiene 174(4): 364-374
1981
ISSN/ISBN: 0932-6073 PMID: 7340297 Document Number: 177897
The time of survival of a wastewater bacterial community in brackish water was determined under controlled environmental conditions. Laboratory experiments in flasks were carried out with a seawater/wastewater mixture from a sewage outfall in the Kiel Bight with and without addition of sediment. The sediment samples were used native or sterilized by autoclaving for the experiments. The number of total and fecal coliforms, enterococci and saprophytic bacteria were determined by plate counts or by the membranefiltration method. A continuous decrease of all enteric bacteria was found in the water column (Fig. 1 and 2), this decrease was much slower in experiments with sediment addition in the culture vessels, especially when the sediment had been sterilized (Fig. 3). The results of the saprophytic bacteria counts did not show such a clear tendency. It was shown that the bacteria got into the sediment and survived there longer than in the water column (Fig. 4 and 5). The saprophytic and even the total coliform bacteria multiply in sterilized sediment probably due to the higher content of easy digestible organic nutrients.