Evaluating the use of small woody feature data in European environmental policies : a fitness for purpose analysis

The Copernicus Land Monitoring Service's Small Woody Features (SWF) High Resolution Layer provides data on European landscape elements that are crucial for biodiversity and ecosystem services. Our report assesses the SWF's fitness for purpose, particularly its ability to inform the Common Agricultural Policy's indicator I.21. Although the SWF 2018 product offers significant insights, we discovered inconsistencies and quality concerns. These issues include discrepancies between the SWF raster data and their original (parent) dataset, as well as deviations from geometric specifications in linear features. Moreover, internal validation seems to overestimate user and producer accuracies by over 40% compared to external validation with the LUCAS (Land Use/Cover Area frame Survey) dataset. Even if LUCAS is not the optimal reference dataset, the disparity between different validations emphasizes the need for more stringent validation protocols and reference data. Our investigation underlines the necessity for expanded accuracy metrics and spatially detailed reporting to accurately reflect the varied European landscape. To enhance policy relevance, we recommend implementing rigorous quality assurance measures, improving validation procedures, and introducing clear tracking and communication of uncertainties. These steps are critical for ensuring the reliability of the next generation of SWF products in shaping future environmental policies and meeting the EU's biodiversity targets.