Based on diameter class data from 140 samples of Eucalyptus urophylla and 383 samples of E. grandis × E. urophylla,a bark-included taper equation was formulated. This equation was then utilized to estimate the total stem volumes of these samples,as well as the volume of top-logs from each tree-logs that are usually sold as pulpwood due their small diameters. A yield table of top-log pulpwood of the two species was then compiled. Meanwhile,a volume calculator for the grade of logs was also developed. The result showed that the total relative error and average systematic error of the yield table for the pulpwood top-logs of these two species were less than 5.0％,while the average percent standard error was less than 9.0％ and estimation accuracy was over 96.0％. All accuracy indicators meet the accuracy requirements for developing forestry data table models. The results of this study can be broadly applied to the inspection of Eucalyptus spp. logging areas and forest asset evaluations in Guangxi,thereby providing a theoretical basis and a measurement table for the accurate estimation of the yield of Eucalyptus spp. top-logs for pulpwood.
维普
万方数据