Wells, Naomi2023-07-122023-07-122022-10-102022https://hdl.handle.net/10182/16307Flowing aquatic ecosystems (e.g., rivers, streams, drains, estuaries) both transport nitrogen and host variable biogeochemical nitrogen reactions, which makes it difficult to identify the origin of the nitrous oxide (N₂O) these systems emit to the atmosphere. This may explain why surface water nitrate concentrations (commonly used to predict aquatic N₂O emissions) turn out to be a poor proxy for N₂O: data from a range of coastal wetlands, streams, and rivers across Australia and New Zealand show that low nitrate waterways can be both net N₂O sources and sinks. Here I bring together observations over temporal (diurnal and tidal cycles) and spatial (within and between systems) scales across a range of aquatic ecosystems to demonstrate the potential of isotopic (δ15NN₂O, δ18ON₂O) and isotopomer site preference (SPN₂O) data to deconvolute the drivers of aquatic N₂O.Conference Contribution - unpublished2023-07-09