Data comprises abundance measures of mites, collembola and plant biomass collected from a field experiment based at Sourhope. Experimental plots varied in nitrogen addition treatment and level of ground disturbance. The data were collected as a component of 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)'s farm at Sourhope in the Scottish Borders. During this time, the site was monitored to assess changes in aboveground biomass production (productivity), species composition and relative abundance (diversity).