Detection of potential illegal environmental activities in Slovakia based on earth observation data

This study outlines a methodology for detecting potential illegal environmental activities in Slovakia using Earth observation data, focusing on the destruction of protected grasslands and non-forest woody vegetation, ecosystems essential for climate resilience. Experimental areas were selected based on illegal activities identified by the Slovak Environmental Inspectorate between 2017 and 2022. A custom web application, developed in the Google Earth Engine environment, was utilised for visualisation and verification, integrating the Normalised Difference Vegetation Index and the Bare Soil Index generated from the Sentinel-2 satellite imagery. The cutting of non-forest woody vegetation was identified through NDVI anomalies, indicating disruptions in vegetation phenology. At the same time, lower NDVI values and changes in surface reflectance detected the destruction of grasslands. The results highlight the usefulness of optical remote sensing data for detecting landscape transformations. However, challenges remain in distinguishing between legal and illegal activities and their representation through maps and infographics.