Assessing land‐use change in Ireland using a high resolution spatial database: The potential of the Land‐Parcel Identification System (LPIS) Jesko Zimmermann 1, *, Phillip O’Brien 2 , Stuart Green 3 , Ainhoa Gonzales del Campo 1,4 , Michael B. Jones 1 and Jane Stout 1,4 1 School of Natural Sciences, Trinity College Dublin 2 Climate Change Unit, EPA, Richview, Dublin 3 Spatial Analysis Unit, Teagasc, Ashtown 4 Trinity Centre for Biodiversity Research, Trinity College Dublin *[email protected] Background The role of vegetation cover and soil in the carbon cycle is well understood. Global emissions have been estimated to be around 0.5 - 2.7 Gt C yr -1 (1990 - 2000), with a long-term loss of 124Pg C to the atmosphere. Major sources of emission are land-use change from forestry to agriculture and form grassland to cropland., though reversing the processes can foster carbon sequestration. Therefore, land-use and land-use change related greenhouse gas dynamics are covered by article 3.4 in the Kyoto protocol. Figure 1: Land-use dependency of greenhouse gas dynamics. Dynamics in grassland are strongly depending on land- use history. (Image from Google Earth) The land-parcel identification system Spatial database originally created to help authorities and farmers with single farm payment scheme. Spatially explicit information on land-use for each parcel allows for: • Including spatial context into grassland classification, adding auxiliary information. • Allows tracking change of single parcels through time. Limitations: LPIS was designed for different purpose, therefore a number of limitations exist: • Parcels duplication (e.g. commonage). • Ambiguous land-use classification. • Changes of parcel outlines through time. • No unique land-parcel identification codes for temporal tracking. Figure 2: Image of land-parcels as present in the land-parcel identification system (Year 2012). Figure 3: Land-use categories for the Republic of Ireland (2012 data). Figure 4: Amount of land-use changes in stable parcels between 2000 and 2012. Adapting LPIS Raw LPIS data Manual removal of large faulty parcels Removal of duplicati on parcels Assignment of land-use classes Assignme nt of unique IDs Suitable for reading out land-use and land-use change Conclusions LPIS has a strong potential for assessing land-use and land-use change with regards to greenhouse gas dynamics, as it allows for spatial tracking of single land-parcels, allowing to overlay auxiliary data, and land-use change tracking. However it requires a number of adaptations to be suitable for this purpose. Furthermore, not all land- use classes within the dataset are suitable (e.g. forestry which does not comply for EU subsides and is therefore only sparsely reported in LPIS). The challenge Currently land-use and land-use change in Ireland are estimated from national statistical data provided by the Central Statistics Office (CSO). Data only offers absolute areas and is not spatially explicit. This leads to a number of limitations: • Not accounting for management practices • No inclusion of spatially explicit auxiliary data (e.g. soil, climate) • Inaccuracy due to assumptions when modelling land-use change from changes in absolute areas.