N2O is a major greenhouse gas. From the soil into the groundwater leached nitrate can be denitrified and N2O is an obligate intermediate product of the denitrification reaction. We work in the Fuhrberger Feld aquifer that is in the north of Germany. In this aquifer, autotrophic denitrification is the main process in terms of nitrate consumption. However, heterotrophic denitrification also occurs in the surface groundwater. We investigated the first two meters below the groundwater surface in a representative strip of 11 km2 that follows a groundwater flowline. We analysed the spatial and temporal variability of N2O concentrations and its influencing factors in the groundwater (DOC, CO2, O2, NO3, SO4-concentrations, redox potential and pH-value) and in the sediment (C and S). Our assumption was, that the spatial and temporal variability of N2O concentrations is governed by these factors. We installed 6 multilevel sampling wells along the groundwater flowline which were sampled monthly over a period of one year. Additionally, we sampled 3 transects of 12 m length every 0.20 m at two specific times. The temporal variability is defined by the monthly sampling of the 6 multilevel sampling wells. A higher time resolution is realized by an additional multilevel sampling well, which was sampled every week. At two specific times, one multilevel sampling well was sampled every two days over a period of one week. We will present the spatial variability of N2O concentrations and its influencing factors at scales ranging from 0.2 m up to 1500 m, and the temporal variability from two day sampling intervals up to one month. We will present the importance of the influencing factors of N2O in the groundwater, estimate the importance of the heterotrophic versus the autotrophic denitrification and elucidate the relevance of DOC versus sedimentary carbon.