Obtaining locally reliable information for GIS-based forest management
1996
Lowell, K. (Universite Laval, Quebec (Canada). Centre de recherche en geomatique)
Geographic information systems are often sold to forest managers by demonstrating that one can point to a location on a map and obtain the wood volume (or tree height, etc.) for that location. But the information with which a GIS responds to such a query is based on a forest inventory planned and executed over a large area whose target precision is global and not local. Thus the forest information provided by the GIS is not actually locally reliable, and the precision of a response to a spatial query is dependent primarily on the variability of the forest type queried. Three experiments are described which were conducted in an attempt to obtain locally reliable forest information. The first conducted spatial interpolation for forest volume between sample plots of various sizes and located at various spacings. The second attempted to establish links between the basal area information collected at the sample plot locations and ancillary ecophysiographic information obtained from existing maps and also derived using Geomatic techniques. The third treated high resolution digital imagery of a forest to identify individual tree stems algorithmically. It appears that the third method is the most promising although much more work remains to be done to refine this method and render it operational
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