ULTRA-HIGH RESOLUTION MAPS AND MODELS AS TOOLS FOR MANAGING AND MONITORING ENVIRONMENTALLY SENSITIVE GEOSITES (ESTRELA UNESCO GLOBAL GEOPARK, PORTUGAL)

This paper focuses on the interpretation of the natural components presents at different geosites in the Estrela UNESCO Global Geopark and on the analysis of soil erosion dynamics associated with trampling events in recent years. Three areas were evaluated: Salgadeiras - Covao da Clareza, Lagoa Seca and Covao do Boi. On there, UAV photogrammetry surveys were applied to obtain orthomosaics and dense clouds that then were used like background at the successive steps of the analysis. The high resolution of the point cloud and orthomosaics allowed us to identify and cartography the geology, hydrography, and vegetation features presents in each place. Besides all trampling sectors were mapped, establishing thus areas potentially vulnerable to environmental degradation because of walk-induced erosion. The analysis presented at this work evidenced an increase in the trampling areas in all the geosites considered, evidencing the potential of this tool like support for future sustainable management of protected areas. This research was supported by the Foundation for Science and Technology (FCT) within the scope of the project Avaliacao de sistemas aereos inteligentes de baixo-custo para mapeamento 3D da superficies of terrene (PTDC/EAM-REM/30475/2014) and by Estrela UNESCO Global Geopark.