Evaluation of Remotely Piloted Aircraft Systems (RPAS)-based Structure-fromMotion (SfM) photogrammetry for characterizing microtopography and vegetation structure in a southeastern Ontario peatland

Abstract

Remotely piloted aircraft systems are increasingly used as a remote sensing platform for peatland researchers to monitor changes in vegetation height/composition/structure. In this work, an RPAS was flown to collect aerial images over Alfred Bog, a domed peatland complex located in Eastern Ontario. The images were processed with a photogrammetry technique referred to as Structurefrom-Motion (SfM) which can be used to create 3D point clouds of a x by y transect. The point cloud results were used to assess the utility of extracting ground terrain and vegetation height as compared to a transect field survey. This field survey was completed with a Trimble Catalyst RTK GNSS to record ground elevation and maximum vegetation height of the canopy top. The results from this research suggest that terrain information could not be extracted at all from the generated point clouds. Although, a digital surface model can be generated to model the canopy top and crown area.