Author ORCID Identifier
Year of Publication
Master of Science (MS)
Arts and Sciences
Earth and Environmental Sciences (Geology)
Dr. Alan Fryar
Typically, the degree of fecal contamination of water is assessed by the concentration of thermotolerant coliforms, like E. coli. This method is time-consuming, taking > 18 hours between the start of incubation and subsequent enumeration. The current study examines the utility of monitoring tryptophan-like fluorescence (TLF) using in-situ fluorometers as a proxy for fecal contamination, particularly E. coli. Relative timing of discharge peaks and TLF peaks is considered, as well as differences in E. coli concentrations and major anion concentrations between two different basins that were monitored weekly. Results indicate that TLF is somewhat useful in the prediction of E. coli within the basin of interest, but the predictive model is strengthened by incorporating other environmental parameters. Additionally, a competing model of E. coli prediction did not include TLF. Overall, TLF is moderately positively correlated to E. coli, but the relationship is not robust enough to justify using it over more easily and affordably monitored proxies. TLF peaks correspond to discharge peaks, usually occurring ~ 6 to ~ 53.5 hours after discharge peaks but sometimes occurring ~ 1 to ~ 24 hours prior to discharge peaks. Differences in major anion concentrations between basins may reflect differences in land use.
Digital Object Identifier (DOI)
This study was supported by the United States Geological Survey's 104b grant (3210002069) in 2021
This study was supported by the University of Kentucky College of Agriculture, Food and Environment's Kerri Casner Environmental Sciences Fellowship in 2021.
This study was supported by the Karst Waters Institute's William L. Wilson and Diane C. Wilson Scholarship in Karst Science in 2021
This study was supported by the Kentucky Geological Survey's Commonwealth Research Assistantship in 2021 and 2022.
This study was supported by the University of Kentucky College of Arts and Sciences (Department of Earth and Environmental Sciences) Pirtle Fellowship in 2021 and 2022
This study was supported by the University of Kentucky College of Arts and Sciences (Department of Earth and Environmental Sciences) Ferm Grant in 2021 and 2022
Dapkus, Ryan, "Tryptophan-Like Fluorescence and Non-Point Source Pollution in Karst Basins, Inner Bluegrass Region, Kentucky" (2022). Theses and Dissertations--Earth and Environmental Sciences. 96.