SURVIVAL AND TRANSPORT OF BACTEROIDES IN STREAMS

A series of lab and field experiments are being designed to test both physical and chemical factors which may affect the persistence of the fecal indicator Bacteroides in stream water. The lab experiments will involve batch tests of stream water spiked with fecal matter and subjected to different temperatures, concentrations, agitation and light to examine the influence of these factors on the persistence of Bacteroides and other fecal indicators. It is hypothesized that the persistence of Bacteroides will be greatest under conditions, such as cold temperatures, which inhibit grazing by microinvertebrates. After the laboratory testing is carried out the persistence of Bacteroides in natural streams will be evaluated by placing diffusion cells containing fecal matter directly in a creek and monitoring concentration decline under natural physical and chemical conditions. In all of the lab and field studies, concentration of Bacteroides will be evaluated using quantitative real-time PCR assays developed at the University of Tennessee. This method will provide a quantitative analysis of Bacteroides persistence and rate of concentration decline, as opposed to precious studies which only measured presence or absence of bacteria.