A study comparing the resolution of Single Photon LiDAR and Traditional Linear Mode LiDAR in order to detect boulders over a region in Klyftamon, Västra Götaland

Abstract

This study aims to compare two sets of LiDAR, one being Single Photon LiDAR and the other one being the regular LiDAR with 2 meters resolution. The two LiDAR datasets cover an area over Klyftamon, a nature reserve located in Skara, Västra Götaland, known for its geological history with the Baltic Ice Lake. Two areas were selected in Klyftamon that were abundant in boulders, with the aim is to test which of the two sets of LiDAR data can detect the boulders. Aside from the main purpose, it is interesting to see if the relatively new technology of Single Photon LiDAR can be used in the field of geomorphology. What can be noted from this study is that it is possible to detect boulders, adjustment from hillshade maps to slope maps had to be made for the detection of boulders. However, given the fine pixel resolution of 0.2 meters, not a lot of boulders were detected with the SPL. What was shown in the study was that Single Photon LiDAR worked better for analysis in bouldery areas that lacked vegetation, some boulders could be identified, but not all. In the treecovered area, no boulders could be seen. However, the use of drone photos turned out to be useful. The drone data gave a high-resolution image, where the boulders that were measured could be identified more easily than it could with the SPL data alone.