The dataset comprises nitrous oxide (N2O) flux data, collected from static chambers as part of a study to determine how land management affected nitrogen cycling by nitrifiers and denitrifiers in an upland agricultural grassland soil and to determine the effects of changing environmental conditions on nitric and nitrous oxide production and emission as a result of land management. Data were collected during a project funded under the NERC Soil Biodiversity Programme, established in 1999 and centred upon the intensive study of a large field experiment located at the Macaulay Land Use Research Institute (now the James Hutton Institute) farm at Sourhope in the Scottish Borders (Grid reference: NT8545019630). During the experiment, the site was monitored to assess changes in above-ground biomass production (productivity), species composition and relative abundance (diversity).