Making the best of both worlds: Can high-resolution agricultural administrative data support the assessment of High Nature Value farmlands across Europe?

Worldwide, the role of farmlands for biodiversity conservation and the delivery of multiple ecosystemservices has been widely acknowledged. In the European Union (EU), societal demands to include envi-ronmental conservation concerns within the Common Agricultural Policy (CAP) have resulted in therecognition of the importance of maintaining High Nature Value farmlands (HNVf).HNVf constitute complex social-ecological systems, which owe their nature conservation value to themaintenance of specific, mostly low-intensity farming systems, supporting high levels of species andhabitats dependent on agricultural practices. Even though HNVf assessment in space and time is essentialto evaluate the effectiveness of Rural Development Programmes, the diversity of rural landscapes acrossEU, the scarcity of data on farming systems, and the lack of common methodological guidelines hashampered the implementation of HNVf mapping and monitoring across Europe. Thus, there is a pressingneed to develop and test methodological approaches that may support HNVf assessment across the EU.The Integrated Administration and Control System (IACS) which is mandatory for all EU Member Statesconstitutes a system for the management and control of CAP payments to farmers. Essentially, IACS com-prises high-resolution, spatially explicit information on the type and intensity of agricultural land-use.Even though such data exhibits high thematic, spatial and temporal resolution, IACS has seldom beenused, due to significant access restrictions. Here, the potential to use IACS data to support the assessmentof HNVf was evaluated within the German Federal State of Lower Saxony by implementing a recentlydeveloped methodological framework. Sets of indicators known to be essential for identifying potentialHNVf and underlying farming systems (expressing landscape structure and composition, farming sys-tems, and crop diversity), were derived from IACS. Spatial patterns of indicators were analyzed at twodifferent scales to delineate the potential distribution of HNVf across Lower Saxony.Results highlighted that most regions in Lower Saxony were characterized by intensive farming prac-tices including high livestock density, high share of intensive crops and low density of linear elements.Only 3% of the Utilized Agricultural Area (UAA) of Lower Saxony potentially constituted HNVf, withthe majority of HNVf coinciding with mosaics of arable and/or permanent crops and semi-natural fea-tures under less intensive farming practices. Semi-natural grasslands, partially under agri-environmentscheme management contracts, covered roughly 1% of the UAA and were mostly intermingled with otherfarmland habitats in extensively managed agricultural landscapes