Date of Award


Document Type


Degree Name

Doctor of Philosophy (PhD)


College of Science and Mathematics


Earth and Environmental Studies

Thesis Sponsor/Dissertation Chair/Project Chair

Meiyin Wu

Committee Member

Huan Feng

Committee Member

Joshua Galster

Committee Member

Lee Lee

Committee Member

Stanley Stephansen


Exacerbation of extreme weather events and increasing urbanization are facilitating the pathway of pollutants towards the waterbodies with freshwater ecosystems being impacted more than terrestrial and marine ecosystems by anthropogenic stressors. We addressed here the three major threats to freshwater ecosystems, pathogens, litter, and eutrophication, integrating scientific findings with management inputs at the watershed level. We evaluated the relationship between environmental variables measurements and Escherichia coli counts with the intent to develop equations capable of predicting near-real-time E. coli concentrations in two riverine ecosystems to help decision makers in assessments of recreational safety. Results showed that the cumulative rainfall for the 72 hours antecedent the sampling, among other predictors, can estimate the microbiological safety of a waterbody for recreational purposes. Additionally, we conducted an on-land investigation of street litter in an urban selected watershed, quantifying and qualifying waste contributions and identifying areas where to develop strategies for reduction of plastic items entering the waterways. We found that despite the heterogeneity in the quantified street litter between the surveyed locations, common patterns exist and should be addressed first while making management decisions. Reducing improper disposal of cigarette butts and drink-food related items are certainly top priorities and these efforts should be coupled with implementing waste disposal strategies close to schools and in neighborhoods where people mostly walk or take public transportation. Finally, we performed a water and sediment study at two eutrophied lakes, with the goals of assessing their water quality, identifying evident changes, and prioritizing locations in need of attention or intervention. We confirmed the eutrophied status of two investigated lakes, assessed a worsening water quality condition of one of the two lakes due to increased total phosphorus (TP) concentrations, and suggested locations that should receive more attention in terms of monitoring and prevention for controlling the TP loads and improve water quality of these lakes. Our studies provide a complimentary approach when addressing three major water quality concerns in New Jersey, coupling the scientific investigation with the management needs and emphasizing the importance of integrating water quality management and watershed context.

File Format