We cordially invite everybody interested to our next open GIScience colloquium talk
The speaker is Moritz Bruggisser
TU Wien, Department of Geodesy and Geoinformation, Photogrammetry Division
When: Monday 06.05.2019, 2:15 pm
Where: INF 348, room 015 (Institute of Geography, Heidelberg University)
Multi-scale laser scanning for forestry applications
Airborne laser scanning (ALS) has been used for the derivation of forest structure descriptors and forest inventory (FI) parameters on an operational level for more than two decades. Mobilization costs of ALS missions, however, are high and ALS acquisitions typically are performed at intervals of several years only. With the advent of laser scanning systems that are operated from the ground (terrestrial laser scanning, TLS) or mounted on unmanned aerial vehicles (ULS), we have promising means at hand for the update of existing FIs on local scales at regular and shorter time intervals. Apart from lower mobilization costs, these latter systems provide a much higher level of detail than could be achieved through traditional ALS missions. This high level of detail allows for the retrieval of FI-parameters as, e.g., the diameter at breast height or stem volumes directly from the point cloud and, therefore, have the potential to partly substitute traditional in-situ FI-measurements. Compared to in-situ measurements, ULS is able to cover larger plots and transects, respectively. Thus, the question is how this new type of reference data can be linked to traditional forest structure metrics derived from ALS data. The comparability of the retrieved structure metrics, however, is a crucial aspect if data from different laser scanning platforms should be combined across scales. In the presentation, I will discuss the possibilities for the derivation of forest structure metrics from laser scanning data and, in particular, present the opportunities of today’s TLS and ULS systems for forestry applications. Furthermore, I will shed light on the differences between forest structure metrics derived from ULS and ALS and show first results from a comparison of the two systems.