SINK OR SOURCE: INVESTIGATING N2O DYNAMICS IN NATURAL PONDS ACROSS NEW YORK STATE

Nitrous oxide (N2O) is an important greenhouse gas (GHG) with a global warming potential 273 times greater than carbon dioxide in a 100-year time period. Ponds are biogeochemical hotspots that may be key sinks for N2O. However, what is driving the potential N2O sink or source dynamics in ponds and variability across ponds remains poorly understood. Therefore, we are exploring: (i) How variable N2O concentrations are across natural ponds and in surface vs. bottom waters, and (ii) What the main physicochemical drivers are of N2O sources versus sinks in these natural ponds. We sampled 14 natural ponds across the four dominant ecoregions of New York State (northeastern, U.S.) twice in summer 2024. In each sampling round, we measured dissolved N2O gas concentrations in surface and bottom waters, and collected a suite of physicochemical variables (e.g., temperature, oxygen, pH, nitrate, and organic carbon). Our preliminary results show during both rounds of sampling, the bottom waters of our ponds remained more undersaturated in N2O while our surface waters may shift from sources to sinks of N2O. Together, our findings will provide a more holistic understanding of N2O dynamics in natural ponds and potential drivers of N2O production and consumption.   

Presentation Preference: Poster

Primary Presenter: Kaci Zarek, Cornell University (kacizarek10@gmail.com)

Authors:

Kaci Zarek, Cornell University  (kz367@cornell.edu)

Pascal Bodmer, Cornell University  (pb577@cornell.edu)

Abigail Bar, Cornell University  (ab3223@cornell.edu)

Meredith Holgerson, Cornell University  (meredith.holgerson@cornell.edu)