Institute at Brown for Environment and Society

Anthropogenic changes to nutrient cycling have dramatically altered ecosystems across the globe, particularly in coastal estuaries such as Narragansett Bay, RI where nitrogen (N) limits primary production. Atmospheric deposition of N into the Bay (through precipitation, direct diffusion, and the settling of particulates) remains poorly quantified, and recent work has found a relationship between precipitation amount and hypoxic events that implies N cycling in the Bay is not fully understood.

To better understand the biological implications of this uncertain flux, I first analyzed high time resolution buoy data collected by the Narragansett Bay Commission and precipitation records to identify multi-day correlations between precipitation events and chlorophyll abundance. I then sampled macroalgae (Ulva spp.) in the Providence River and northern Narragansett Bay at ~48 hour time resolution to investigate if the d15N and C:N ratio of macroalgae changes in response to precipitation.

Finally, I am collaborating on a project to quantify the flux of gaseous NH3 and particulate NH4+ between Narragansett Bay and the atmosphere through the use of acid-coated filters and a Relaxed Eddy Accumulation system.