Assessing the distribution and extent of High Nature Value farmland in the Republic of Ireland

• Published in: Ecological indicators 2020-01, Vol.108, p.105700, Article 105700
• Main Authors: Matin, Shafique, Sullivan, Caroline A., Finn, John A., Ó hUallacháin, Daire, Green, Stuart, Meredith, David, Moran, James
• Format: Article
• Language: English
• Subjects: Common Agricultural Policy; GIS; Rural development; Semi-natural habitat; Stocking density
• ISSN: 1470-160X; 1872-7034
• DOI: 10.1016/j.ecolind.2019.105700

•Methodology to map High Nature Value farmlands (HNVf) for Ireland at tetrad-scale.•National-scale map to identify the likely distribution of Type I and II HNVf in Ireland.•33.7% of farmland tetrads in ROI had a high or very high likelihood of being HNVf.•Of the farmland tetrads likely to be HNVf, about 54% partly or wholly coincided with Natura 2000 sites, and 53% were in upland areas.•Of the farmland tetrads likely to be HNVf, 84% partly or wholly coincided with NPWS priority areas for agri-environment schemes. High Nature Value farmland (HNVf) is managed farmland that has high biodiversity and often supports species of conservation concern. Assessing the distribution and extent of such farmlands is useful for appropriate targeting of conservation measures and supporting associated rural communities. The conservation of species and habitats within HNVf is also among the aims of the EU’s (European Union) Biodiversity Strategy and is a focus of the Common Agricultural Policy (CAP) Rural Development Programme. Data on HNVf distribution and extent is required for both policy implementations under the CAP for income support payments and reporting within the EU Biodiversity strategy. Here, we extend the scope of the methodology from a previous study by presenting a finer spatial resolution to map the likely distribution of HNVf in the Republic of Ireland using indicators adapted for the Irish context and weighted based on expert knowledge and literature. The indicators (and weighting) used were: semi-natural habitat cover (40%, from CORINE land cover), stocking density (30%, from Land Parcel Information System; LPIS), hedgerow/scrub cover (10%), river and stream density (10%), and soil diversity (10%). Indicators were included in a weighted sum model (WSM) that combined raster indicator inputs, representing relative weights and the output had a tetrad-scale (2 km × 2 km) resolution. We used various datasets (national nature designations, Irish semi-natural grasslands survey, intensive farmland points and field points with semi-natural habitats) to validate the final HNVf map. To do this, all datasets were converted from polygon to point data format by considering the centroid of the polygon as the data point and overlaid on the HNVf map to assess the possible incidence. Of the 13,660 tetrads defined as farmland in the analysis, 4602 (33.7%) had a high or very high likelihood of being HNVf. About 54% of the latter set of tetrads partly or wholly coincided with