Assessment of water erosion on hiking trails in Alvão Natural Park, Portugal = Evaluación de la erosión hídrica de las rutas de senderismo en el Parque Natural de Alvão, Portugal

Abstract

This study presents a methodology to identify and characterize pour points and their contribution areas along hiking trails to assess vulnerability to water erosion. A segment of the PR3 - Fisgas de Ermelo trail in Alvão Natural Park (Portugal) is analysed using high-resolution LiDAR data and ArcGIS Pro tools. Of the 16 pour points identified, 38% are on slopes over 20% and 50% have large upstream catchments (>100 m²), indicating a high erosion risk. Fieldwork confirmed gullies, rills, and sparse vegetation in runoff-concentrated zones. This approach helps managers identify critical areas for intervention, improving environmental protection, trail stability, and user safety.