Potential of Aerial Image-Based Monoscopic and Multiview Single-Tree Forest Inventory: A Simulation Approach
Authors: Korpela, Ilkka Sakari1; Tokola, Timo Erkki1
Source: Forest Science, Volume 52, Number 2, April 2006 , pp. 136-147(12)
Abstract:
Two aerial image-based estimation chains were compared for their potential in the assessment of timber resources. The two chains consisted of two- and three-dimensional image measurements followed by indirect model estimation. The effects of various errors at both the single-tree and stand levels were examined with Monte Carlo simulation. The three-dimensional multiview estimation chain with height measurements of individual trees proved less prone to random and systematic errors than the monoscopic chain. An upper limit of accuracy at the single-tree level is determined mainly by the allometric correlations. Volume estimates of single trees showed estimation accuracies (root-mean-square error, RMSE) of ∼15–20% and 35–40% in the multiview and monoscopic chains, respectively. This is lower than the accuracy achievable in the field, which is ∼6%. Image-based single-tree forest inventory is prone to systematic measurement and model errors, and in a simulation for the total effect of error sources, upper estimation accuracies (RMSE) of ∼15% and 30% for stand volume were computed using full mapping of the stand with the multiview and monoscopic estimation chains, respectively.Keywords: Volume; diameter; species; photogrammetry; allometry
Document Type: Research article
Affiliations: 1: Ilkka Sakari Korpela, University of Helsinki, Department of Forest Resource Management, PO Box 27, FIN-00014 Helsinki, Finland— helsinki.fi/∼korpela , ilkka.korpela@hut.fi, Timo Erkki Tokola, University of Helsinki, Department of Forest Resource Management, PO Box 27, FIN-00014 Helsinki, Finland—timo.tokola@helsinki.fi., Email: ilkka.korpela@helsinki.fi, URL: http://honeybee.helsinki.fi/mmvar/henkilokunta/professorit/tokola/index.htm.
