Estimating Dry Mass Of Logging Residues From Final Cuttings Using A Harvester Data Management System
Authors
Nuutti Kiljunen
University of Joensuu, Joensuu, Finland
Abstract
A method and functions are introduced for estimating the dry mass of logging residues for the most common Scandinavian tree species. Functions were formulated for single trees using different combinations of independent variables that can be measured by standard measuring equipment on harvesters. Cross-validation was used to test the functions and to assess their validity. According to the cross-validation, the total dry mass of logging residues in a clear-cut area could be estimated with a relative standard error of 9.4 - 11.2%. For individual trees, however, the relative standard error for estimating the dry mass of logging residues was as high as 21.5 - 27.6%, depending on the tree species and on the independent variables used in the functions. The models introduced were however more accurate than the generally applied method of estimation, which is based on the average ratio of the dry mass of logging residues to the volume of merchantable wood.
