원문정보
초록
영어
The precision level of forest inventory assessment is a key factor in the forest industry to optimize timber value and forest management planning. Light Detection and Ranging (LiDAR) application in forestry has recently introduced an effective tool to estimate and monitor the precision level of forest inventory. This research investigates the opportunities and limitations of integrated MLS and ALS LiDAR application in estimating individual tree DBH and tree height. The three circular fitting algorithms(integrated RANSAC and circle fitting , minimum enclosing circle, least squares Ellipse fitting) were used to estimate the DBH. In addition, the height was calculated by the Crown Height Model (CHM). The result of DBH estimation was the most accurate in Ellipse fitting algorithm. To compare previous circular fitting applications, integrated MLS and ALS had better performance estimating tree DBH. Lastly, the estimated tree height using CHM was compared with the ground truth, and R2, RMSE of height are 0.60, 2.0 m. Also, the trends of less accuracy in small trees were identified in PCDs extraction at the detect of tree top from the overlapped PCDs among the surrounded tall trees PCDs. This result indicated that small trees are limited to segment top of tree PCDs due to overlaps by tall trees in high dense forest structures. Also, taller trees have limited to capturing ground point due to the high dense of forest crown.