Canadian Forest Service Publications
Détection du pin blanc dans l’Outaouais à partir d’images satellitaires à haute résolution IKONOS. 2001. Gougeon, F.A.; Labrecque, P.; Guérin, M.; Leckie, D.G.; Dawson, A. 23rd Canadian Symposium on Remote Sensing / 10e Congrès de l’Association québécoise de télédétection (CD-ROM), August 21-24, 2001, Sainte-Foy, Québec, Canada. Canadian Aeronautics and Space Institute, Ottawa, ON.
Issued by: Pacific Forestry Centre
Catalog ID: 18347
Availability: PDF (download)
The intensification of forest management implies the acquisition of information with ever increasing precision. Fortunately, research done using high spatial resolution (10-100 cm/pixel) aerial images allow us to think in terms of semi-automatic individual tree crown species identification and stand delineation on an operational basis in the no-so-distant future. The recent availability of the IKONOS satellite (1 m/pixel) also opens new horizons for forest inventory. Within this framework, a research project was carried out to evaluate the potential of white pine detection from IKONOS images and to compare the efficiency of the ITC (Individual Tree Crown) suite on pan-sharpened and on separate panchromatic/multispectral IKONOS images.
The panchromatic (1m/pixel), multispectral (4m/pixel), and pan-sharpened (1m/pixel) versions of an IKONOS scene of a region in the Quebec North-West (46°N, 77°W) were acquired and analysed with the ITC suite. After smoothing the image and creating masks of the non-forested areas, the individual tree crowns were delineated by following the valleys of shade between them. Signatures were created for white pine and a few other species and then, crowns were classified individually by a maximum likelihood process. In spite of haze over a significant part of the scene, the white pine inventory appears remarkably precise when compared with the interpretation of infrared aerial photographs and with ground plots. The use of the pan-sharpened image does not appear to hinder crown classification and that of separate panchromatic and multispectral images, although more costly, brings additional precision to stem counts.