Home // BIONATURE 2017, The Eighth International Conference on Bioenvironment, Biodiversity and Renewable Energies // View article
Authors:
Benoît St-Onge
Simon Grandin
Keywords: forest; subarctic; WorldView; height, biomass
Abstract:
Subarctic forests are open woodlands sparsely populated by small trees having narrow crowns. They cover, in Canada alone, an area of more than 2.5 million km2. Spread between the 50th and 70th northern parallels, these forests fall within the regions that are experiencing some of the greatest climate change that will likely induce variations in forest biomass. These changes could go undocumented due to the high costs of data acquisition in such remote areas of Canada. Airborne surveys (photo or lidar) are logistically difficult, and conventional remote sensing based on 2D satellite images (e.g., Landsat) lacks accuracy. Our goals are therefore to use new very high resolution satellite stereo images (31 cm pixels) to reconstruct 3D models of subarctic forests, and use historical stereo aerial photos acquired since the 1950s to create similar 3D models representing the structure of these forests in the past. In this study, we have reconstructed a digital terrain model (DTM) using stereo measurements on WorldView 3 images of sparsely wooded areas. We then performed similar stereo measurements on the top of trees and calculated their height by subtracting DTM elevations. These height measurements were in good agreement with reference data, and can afterward be used to estimate tree biomass. Similar measurements will be performed on historical aerial photographs, and the tree biomass changes, as a function of tree height and number of trees, will be estimated.
Pages: 22 to 25
Copyright: Copyright (c) IARIA, 2017
Publication date: May 21, 2017
Published in: conference
ISSN: 2308-4154
ISBN: 978-1-61208-561-6
Location: Barcelona, Spain
Dates: from May 21, 2017 to May 25, 2017