| Traditional trail degradation assessment methods can require time- and labor-intensive fieldwork or technical expertise, and the measurements made often consist of a series of 2D cross-sections. Structure from motion technology could potentially be used to improve the accuracy and efficiency trail degradation assessment by creating highly detailed 3D point clouds from a set of unstructured photos. This thesis assesses the accuracy and precision of measurements made from point clouds produced using Microsoft Geosynth. It was found that using a Canon G10 camera and Trimble GPS unit, width, surface area, volume, and slope measurements made from the point clouds were within 2% of the actual measurements. Change analysis of the DEMs generated, however, revealed problems with tilt. Using structure from motion technology to improve trail degradation assessment shows promise, but requires further research to solve the problems encountered in this study before it can be promoted as a valid methodology. |