COS 239-5 - Influence Of Climate Change On drivers of Fecal Indicator Bacteria Dynamics And Microbial Sources Hot Spots In Mixed-Use Watersheds In Subtropical Aquatic Systems

Abstract: Climate change and recent global outbreaks of coronavirus disease have shifted scholarly attention to the spatial and temporal spread of microbial pollution in waterways (especially metropolitan rivers) and its effects on public health. Urban discharge is increasingly being investigated as a potential source of fecal indicator bacteria (FIB), but less is understood about its presence in mixed land use sub-tropical watersheds with constant land cover and climate change. Contamination of the various aquatic systems in NW Florida has become very alarming over the decade. This study area is prone to frequent and severe storm/ rainfall events, and natural disasters. Increased precipitation and resultant runoff coupled with poor and or outdated sewage / septic systems leads to high runoff of these pollutants and subsequent impairment Escherichia coli (EC), were quantified using IDEXX colilert-18 for 300 samples surface samples from January to June 2022, and physicochemical parameters were tested via in situ sonde and ion chromatography monthly. The Pensacola bay system watershed was utilized as the subtropical test area to investigate the climate change and spatiotemporal effects on e coli hit spots and its main driver forces. The interaction among e coli, physicochemical parameters a using Pearson correlation Multiple linear regressions (MLR) and general linear modeling were employed to determine the significant variables that impact elevated FIB levels of the recreational swimming coastal town. Overall, FIB quantities were higher in urban than the vegetated, rural and agricultural areas (In addition, during early summer, FIB is more persistent and grows at a faster rate in warmer environments, however was in abundance and exceedance even in colder months. Nonetheless, intra-event FIB concentrations varied based on site conditions. The correlation between FIB concentrations and environmental parameters was affected by anthropogenic and climatic conditions. Temperature, turbidity, and total dissolved solids, conductivity, and salinity were positively correlated with FIB concentrations. Spatial and temporal variation affected fate, transport and delivery of these pollutants into these aquatic systems. NW Florida watersheds are severely contaminated by fecal inputs from both human and animals inputs and nutrients, immediate bioremediation, best management practices are imperative to mitigate these issues. As a result of the elevated quantity of illnesses, and deaths and the devastating nature of infections caused by the use of fecal-impaired water it is crucial that are able to properly comprehend the cause and effect that control the dispersal of FIB pathogens and nutrients