one publication added to basket [136997] | Long term variations in a protozoan chemostat culture
In: Journal of Experimental Marine Biology and Ecology. Elsevier: New York. ISSN 0022-0981; e-ISSN 1879-1697, more
| |
Keywords |
Aquatic organisms > Food organisms Aquatic organisms > Heterotrophic organisms > Predators Experimental culture Grazing Growth Models > Mathematical models Population characteristics > Population density Uronema marinum Dujardin, 1841 [WoRMS]; Vibrio Pacini, 1854 [WoRMS] Marine/Coastal |
Abstract |
A marine cilated bacteriovorous protozoan, Uronema marinum Dujardin was maintained in the second stage of a 2-stage chemostat. A population of a marine Vibrio sp was maintained at steady state in the first stage on a carbon limited medium, and pumped at constant rate to the second stage where it provided the sole food source for the Uronema marinum. Although a steady state population level was predicted for both organisms in this system, the population density of U.marimum varied, first in damped oscillations, and later cyclically from 600 to 1500 cells/ml with a periodicity of 9-11 days. U.marimum cell size and grazing rate also varied, and the grazing rate was shown to be inversely related to protozoan cell density. An equation is derived relating the grazing rate of U.marinum to its own population density and that of its prey, and the rates predicted from this equation are compared with those observed. |
|