研究目的
The objective of this study is to illustrate a model-based method to use a sample of trees with DBH, tree species and tree height measured from UAV-LS data to predict single tree V and to use the predictions to estimate V at the plot, stand, and forest levels. The proposed method relies solely on UAV-LS and field data (i.e., 58 plots) were used only for independent validation.
研究成果
Forest growing stock volume can be estimated using UAV-LS and image data without the use of field data for calibration. The accuracy of the UAV-LS estimates increased with the spatial scale. At the forest-scale, the UAV-LS estimates were well within the 95% confidence intervals of the estimates of an intense field survey and both estimates had similar precision. The accuracy of the UAV-LS estimates varied given forest structure and was largest in open pine stands and smallest in dense birch or spruce stands.
研究不足
The study was limited by the lower point density compared to previous UAV-LS literature and the reliance on a semi-automated procedure that included manual steps for selecting trees with reliable UAV-LS DBH measurements and classifying tree species. The applicability to different forest types than the ones in this study is unknown and could require tuning of the parameters.