Date of Submission
Academic Programs and Concentrations
Environmental and Urban Studies
Project Advisor 1
Project Advisor 2
My research focused on determining whether or not temporary bodies of water near the Hudson River serve as incubators for river bacteria that can affect human health. I sampled surface waters from the river, adjacent tide pools, and standing puddles near the Germantown, NY boat launch and tested for the presence of microbial agents of concern, including fecal contamination indicators (Enterococcus, coliforms, and Escherichia coli), ampicillin-resistant bacteria, and endotoxins. To better understand bacterial communities in these waters, I sequenced the 16S rRNA gene, which allowed me to identify bacteria to the genus level. Although puddle and tide pool temperatures were not significantly different from the river (p=0.5079; Table 2 and Figure 7), I did detect bacterial differences between different water body types and some influences from the Hudson on tide pools in particular. Differences in enterococci counts (Figure 8) were statistically significant between the puddles and tide pools (p=0.0019) but not between puddles and the river (p=0.0622) or tide pools and the river (p=0.5640). Coliform counts (Figure 9) were different between tide pools and puddles (p=0.0022) as well as between tide pools and the river (p=0.0470), but there was no difference between puddles and the river (p=0.8010). E. coli and ampicillin resistant (Figure 10) bacterial concentrations were not different between sites (p=0.08544 and 0.3589, respectively). Notably, endotoxin concentrations (Figure 11) were different between the river and tide pools (p=0.0097), but not for puddles and the river (p=0.0597) or puddles and tide pools (p=0.1018). Relative abundance at the phylum (Figure 1) and genus (Figure 2) level showed Bacteroidetes (a fecal indicator organism) was more abundant in tide pools than the Hudson (~10% in tide pools, and ~6% in the river) suggesting the idea of incubation; Tetrasphaera and Candidatus pelagibacter genera dominated tide pool (~31%;~16%) and river (~37%;~20%) samples suggesting dominant river influence on tide pools but not on puddles (~1%; Sphingobium was prominent in puddles (~41%) and suggests they are incubators for this bacterial life. Microcystis, a genera of Cyanobacteria which includes toxin-producing organisms, was found to be more abundant in tide pools than any other site (~4% compared to Microcystis, endotoxins), but not all. Because both Microcystis and endotoxins are emerging contaminants of concern, this finding may have public health implications. Also, the high levels of sewage indicators found in puddles indicate the need for greater research into sources for these bacteria in inland waters.
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Winig, Elizabeth Anne, "Lifeguarding the Hudson: Microbial Agents of Concern in Puddles, Tide Pools, and the River" (2015). Senior Projects Spring 2015. 175.
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