Form Submission: Participation Entry

Dissolved organic matter (DOM) is a pivotal variable in aquatic ecosystems that can influence multiple factors, including pH, light penetration, stream metabolism, contaminant mobility, and water-treatment efficiency. Past studies during baseflow in headwaters have shown that urbanization is leading to DOM compositional changes; however, additional research is needed during stormflow at the watershed-scale to facilitate more comprehensive spatiotemporal analyses. For two years during baseflow and stormflow, we sampled a range of stream orders across an urbanization gradient in the Farmington River Watershed, CT, to investigate changes in DOM quality. Our urban vs. forested DOM analyses (via fluorescence spectroscopy and ultrahigh resolution mass spectrometry) showed that urban-derived DOM was lower in molecular weight, enriched in protein-like fluorescence, and comprised of more sulfur- and nitrogen-containing compounds. With the projected increase in intense storm events in the Northeast, better understanding DOM under various land use and hydrologic conditions is critical for watershed management.