Historic grassland survey data with contemporary spatial habitat data for semi-natural grasslands across England

The historic quadrat data was recorded at grassland sites in England between 1960 and 1981, using a standardised methodology. The vegetation in each quadrat was assigned to one of the British National Vegetation Classification (NVC) communities using Tablefit. Quadrats were further classified into one of four grassland types; calcareous grassland, lowland heath and dry acid grassland, mesotrophic grassland and wet grassland. The location of each quadrat surveyed was imported into ESRI ArcGIS v10. A 100m buffer was generated around each individual quadrat to represent a grassland site. To indicate the coverage of semi-natural grassland habitats in 2013, Natural England's Priority Habitats' Inventory was used. The percentage and type of priority habitat contained within each site was calculated in ArcGIS, using the tabulate intersection function in the spatial analyst toolbox. The percentage of each site designated as a SSSI was also calculated using Natural England's digital boundary data for SSSIs.