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Production and accumulation of the major greenhouse gas nitrous oxide (N 2 O) in surface groundwater might contribute to N 2 O emissions to the atmosphere. We report on a 15 N tracer study conducted in the Fuhrberger Feld aquifer in northern Germany. A K 15 NO 3 tracer solution (60 atom%) was applied to the surface groundwater on an 8 m 2 measuring plot using 45 injection points in order to stimulate production of 15 N 2 O by denitrification and to detect its contribution to emissions at the soil surface. Samples from the surface groundwater, from the unsaturated zone and at the soil surface were collected in regular intervals over a 72-days period. Total N 2 O fluxes at the soil surface were low and in a range between -7.6 and 29. , indicating that indirect N 2 O emissions from the surface groundwater of the Fuhrberger Feld aquifer occurring via upward diffusion are hardly significant. Due to these observations we concluded that N 2 O dynamics at the soilatmosphere interface is predominantly governed by topsoil parameters. However, highest 15 N enrichments of N 2 O throughout the profile were obtained in the course of a rapid drawdown of the groundwater table.We assume that such fluctuations may enhance diffusive N 2 O fluxes from the surface groundwater to the atmosphere for a short time.