Understanding existing land use is crucial in making informed decisions on how to make more effective use of land. The National Land Data Programme (NLDP) is working with Ordnance Survey Northern Ireland (OSNI), Northern Ireland’s national mapping agency, to create a combined land cover and use map that will deliver significant benefits to land use decision makers.
Kathryn Weir from OSNI tells us more about the progress of the pilot to date and provides insights into the spatial modelling methods used.
Creating an authoritative land cover and use map
In order to make effective decisions about what we do with our land, we need a consistent baseline of what is on the land surface (land cover) and what the land is being used for (land use). Information on land use and land cover is often held in disparate data sets which vary in accessibility, availability and format. It can therefore be difficult to get a clear picture of land use and land cover across an area, leading to duplication of information gathering by decision makers and ultimately inefficient use of land.
Improving this information can help decision makers identify where change is beneficial and feasible to best optimise land use and manage competing demands. For example, bringing together land use and land cover data can help rural landowners identify areas of agricultural land not currently used for high value crops that could instead become a site for renewable energy. It can also enable urban planners to determine how buildings and green spaces are being used in certain areas to support new housing developments.
Orthophotography of Strabane
“Skin of the Earth”
The Geospatial Commission is funding OSNI to develop a prototype land use and land cover map to help address these challenges. OSNI are taking a wide range of existing, authoritative data sets, using their OSNI Fusion product as the basis of the map. Fusion is the most detailed spatial mapping dataset produced by OSNI, within which land parcels, water features and transport casings form a fully polygonised ‘skin of the earth’ coverage of Northern Ireland, with each polygon having a unique identifier.
OSNI are testing the map initially in the Derry and Strabane district. Geospatial data from public sector organisations, for example, on agriculture, housing, council assets and forestry, is brought together within a Geographical Information System (GIS). Each information type is then assigned a land cover and land use classification based on the National Land Use Database. The use of Fusion allows users to select a polygon on the map which then pulls through both the largest land use and land cover types, overlaid into one product.
This work is intended to contribute to the development of a single mapping specification that can be rolled out to Northern Ireland, which will help contribute to more informed decisions on land use. The map is also extensible, allowing for additional data to be overlayed unlocking further use cases on land ownership, pollution level and biodiversity.
Combined land cover and use map of Strabane with polygons representing land parcels and colours representing land use categories
Where next?
The initial results so far have been positive with a large number of polygons within the sample area being successfully classified.
OSNI will be sharing their findings to gather feedback on the product’s suitability for creating a full map of Northern Ireland, identifying if this method could be used by others to create similar maps across the rest of the UK and to see how well it addresses current problems with land use and cover data. Please contact NLDP@cabinetoffice.gov.uk for more information on how to get involved.