Application of UAV surveys and GIS to investigate factors affecting recreational trail width

Monitoring and managing recreational trails are necessary to promote recreation and conservation of protected natural areas (PNAs). However, the relationship between the usage of recreational trails and its impact on the immediate environment can be complex, where a small increase in number of visitors can cause significant damage, or conversely, intensive usage of recreational trails could have a very minimal impact due to other factors like management practices, trial design, the behaviours of users, soil type and resilience make it a non-linear relationship. This research seeks to assess and investigate the relationship between recreational trail width and several morphometric parameters of the trail and its vicinity (e.g., trail gradient, trail aspect, landform gradient, landform aspect, and topographic wetness index). The main aim of this study is to use geographic information systems (GIS) and unmanned aerial vehicle (UAV) data to produce consistent morphometric information about trail conditions. We present a step-by-step workflow demonstrating how to use orthomosaic and digital elevation models (DEMs) generated from UAV surveys to delimitate trail tread and subsequently provide data on trail width, gradient and aspect in a semi-automatic, objective way. The deliverable of our work is a toolbox for ArcPro, which can be implemented to generate trail and terrain characteristics in any area for which trail tread polygon and DEM are provided. Analysing relationships between trail width and other morphometric parameters will help understand factors affecting trail conditions. This study is supported by Polish National Science Center project OPUS-22 2021/43/B/ST10/00950.