To verify the results of the forest inventory, Alianca Florestal provided data of this forest inventory using a statistical approach with sampling plots for 6 stands with a total size of 75 ha. Based on the information of 18 sample plots the timber volume of all stands was estimated to be 100 m³ / ha.
Furthermore the exact amount of timber volume from harvesting the involved stands was also known. The total timber
volume was 5349.05m³ without bark, which corresponds to a timber volume of about 71 m³ / ha.
In this case the statistical approach overestimates the timber volume by about 40 %. This overestimation may be caused by the selection of sampling plots which did not represent the character of the entire stand very well.
The results achieved with the developed methods based on airborne laser scanner are shown in table 4. The total timber volume without bark was estimated with 4964,14 m³ or 66 m³/ha. Therefore the estimated volume have a correctness of 93% which corresponds to results achieved by Persson ed.al (2002).