Estimated distribution of high nature value forest in the Republic of Ireland

Abstract

High Nature Value (HNV) farmland and forest systems play a vital role in supporting biodiversity and delivery of ecosystem services. Estimates of HNV forest area and distribution in the European Union (EU) are rarely conducted, despite having been a requirement of Rural Development Programmes. This work represents the first attempt to identify and estimate the area of HNV forest in the Republic of Ireland in a repeatable and transparent way. Relevant geo-datasets available for Ireland were collated and analysed. We investigated whether the datasets contained information on the indicators used in a recently-developed Nature Value (NV) index, and explored the potential of proxy indicators to determine the likelihood of a mapped area of forest being HNV. Based on these analyses, a likelihood map of the distribution of forest in different NV categories was produced and an accuracy assessment conducted. Results from this study suggest that HNV forest accounts for approximately 1 % of the Irish land area, or 8 % of the total forest area. Accuracy assessments indicated substantial agreement between the likelihood map classifications and the calculated NV status of National Forest Inventory plots. The methodology presented here could also be applied to existing similar datasets to estimate the extent and distribution of HNV forest in other regions. The mapped output provides a likelihood of a forest area being HNV and can provide evidence to inform the development of forest conservation policies.