QUANTIFYING MECHANISMS DRIVING NUTRIENT DYNAMICS IN STORMWATER PONDS ACROSS AN AGE GRADIENT
Stormwater ponds (SWPs) provide valuable ecosystem functions like flood mitigation and pollutant removal from stormwater runoff. Nitrogen (N) and phosphorus (P) are commonly targeted for removal by these engineered ecosystems. Denitrification is a particularly important N cycling mechanism as it converts bioavailable nitrogen to N2 gas. Studies quantifying N and P dynamics are common in SWPs, but research on the biogeochemical mechanisms driving nutrient flux in SWPs is lacking. To better understand drivers of SWP nutrient cycling, we collected sediment cores from residential stormwater ponds ranging from 10 to 30 years old in North-Central and South Florida. We performed continuous flow core incubations, where sediments were exposed to both ambient and elevated water column nitrate levels. We quantified net N2 fluxes (via membrane-inlet mass spectrometry) and dissolved inorganic nutrient uptake. We hypothesized that denitrification and nutrient removal will increase along the age gradient due to increased organic matter availability, and that denitrification will increase across sites under elevated nitrate levels. Results of this research will provide a mechanistic understanding of nutrient dynamics within stormwater ponds, allowing for development of targeted management actions for enhanced nutrient removal.
Ashley Smyth (Co-Presenter/Co-Author), University of Florida, email@example.com;
Alexander Reisinger (Co-Presenter/Co-Author), University of Florida, firstname.lastname@example.org;
Steven Hohman (Primary Presenter/Author), University of Florida, email@example.com;