we cordially invite everybody interested to our next open GIScience colloquium talk
on Mon, May 08, 2.15 pm,
at the Department of Geography, Heidelberg University, Im Neuenheimer Feld 348, Lecture Hall, Room 015.
The presentation will be given by Harm Bartholomeus (Wageningen).
The topic is:
Investigating Tropical Forests with Unmanned Aerial Vehicles and LiDAR
Constant monitoring of tropical forests is important to increase our knowledge on effects of climate change. However, mapping aspects like forest structure, degradation and deforestation is time-consuming and expensive. Innovative high-tech approaches like Terrestrial Lidar Scanning (TLS) and Hyperspectral Sensing from Unmanned Aerial Vehicles (UAV) may revolutionize the way we monitor our forests. In the last few years, we conducted a number of campaigns to investigate the use of innovative technologies for mapping the plant traits of tropical forest. These campaigns consisted of UAV data acquisition, TLS measurements, or combinations of both techniques. UAV based sensing allows for multi-scale observations and fills the gap between ground based sampling and satellite based observations. Our in-house developed Hyperspectral Mapping System observes both forest structural information, which can be derived from the 3D point cloud data, and the biochemistry of the tree canopy which can be characterized from the hyperspectral data cube. The structure of the forest is assessed with the TLS, where our research focusses on the 3D reconstruction of individual trees by using Quantitative Structural Models (QSMs). These can further be used to determine individual trees biomass and e.g. branch architecture. Upscaling these procedures to the plot level allow less biased biomass estimates than the currently used allometric equations. Finally, some first results of the newly acquired RiCopter UAV based Lidar system will be presented. This system will allow us to upscale our laser scanning activities over larger areas, preserving the high accuracy and point density required for accurate reconstruction of the tree shapes. I will show examples of our work across the tropics, with illustrations from field campaigns in Indonesia, Ghana and Guyana and describe our methods to derive individual tree-level plant traits and plot-level estimates of biomass.