Extraction of Individual Tree Parameters by Using Terrestrial Laser Scanner Data in Hyricanian Forest

Background: In this study for the first time terrestrial laser scanning survey was implemented on upland Hyrcanian forest, through which a and new method was applied to automatically extract DBH and tree position as a necessary step for height calculation and fitting the clustering as a circle. Materials and Methods: Tree height extracted by fixing a cylinder around the trees center. The accuracies of these methods were investigated by field measurement. Among ۴ shapes fitting algorithm, Monte Carlo had more suitable result to fitting circle in each height above the ground. Results: Tree detection rates were ۸۵% for Carpinus betulus and ۸۷% for Diyospyrus lotus with respect to field measurement. R۲ and RMSE for DBH measurement were ۰.۹۸, ۲.۰۶ cm for Carpinus betulus and ۰.۹۸, ۱.۲۶ cm for Diyospyrus lotus. Value of R۲ and RMSE for height measurement were ۰.۹۶, ۳.۳۷ meters and ۰.۹۳, ۳.۰۲ meters for Carpinus betulus and Diyospyrus lotus, respectively.             Conclusions: The accuracy of DBH by TLS is very suitable, and about the height of trees we extracted underestimated value in comparison to field measurement and that we need to develop more effective algorithms in order to reach more accurate measurement of trees’ height in Hyrcanian forest.

کلیدواژه ها:

Breast height ، DTM ، Forest inventory ، LIDAR ، Point cloud