模拟野外实地林分调查场景,设置3种不同的样地大小和扫描精度,应用地面激光扫描(TLS)获取扫描的点云数据,通过最小二乘法对切片上的点云进行圆的拟合,提取特定高度处的上部直径。结果表明,在中精度扫描、10m半径样地时,使用点云提取的上部直径估计值精度最高。该研究旨在保证数据精度的前提下减少扫描的时间和成本,制定使用TLS技术进行林分调查时的参考标准,充分发挥该技术在森林资源调查中的优势。
The study establishes a simulated scenario of forest inventory in plots by using three different sizes of the sample plots and scanning resolution.Point cloud data are acquired by terrestrial laser scanning,and the data are processed by least square method to fit a circle.The diameter of the fitted circle is the top diameter at the specific height.The results show that the accuracy of the estimation of top diameter is highest when the radius of the sample plot is 10m and the scanning resolution is middle.The research aims at setting a reference calibration of forest inventory using TLS,achieving high accuracy and low operational and time cost,taking full advantage of TLS in forest inventory.
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