Constructing and Applying Eucalyptus Volume Model in Guangxi Province
This study aims to investigate the operation design of eucalyptus felling area in Guangxi Province,Chi-na.The forest volume was also estimated by LIDAR,particularly for the decision-making on the forest resource plan-ning.539 eucalyptus sample trees were firstly selected from 276 standard plots in six regions.Tree height,DBH and crown width were then used to establish a one-dimensional DBH volume model(V=0.00017D2.55156),a binary DBH-tree height volume model(V=0.00004354D1.71874 H1.19727)and a binary crown width-tree height volume model by nonlinear model regression method(V=0.0000405602Cw0.86134 H2.44421).Three stumpage volume models were tested in the different areas,DBH,segments of tree height and independent samples.The total relative error(TRE)and average systematic error(ASE)absolute value of each model were less than 5%,and the estimated precision was more than 95.0%.The mean percent standard error(MPSE)was less than 10%,except for the one-dimension-al DBH volume model.The results show that the three stumpage volume models were varied greatly in their applica-tion ranges.Among them,the one-dimensional DBH volume model was accurately and rapidly estimated the accumu-lation of standing trees,with the small workload and simple use,but the model was unstable enough;The two-di-mensional DBH-tree height volume model with the high accuracy and stability was mostly used for the standard wood or standard ground forest tree accumulation,particularly for the shape and tree height curve,but the large workload and the high cost were unsuitable for the large-scale investigation of forest resources;The accuracy of the binary crown width-tree height volume model was better than that of the one-dimensional DBH one,although inferior to the binary DBH-tree height one.Therefore,the binary crown width-tree height volume model can fully meet the accura-cy requirements to obtain the crown width,tree height regional survey and monitoring of forest resources using air-borne LIDAR.Therefore,three models can be applied into the volume survey for the different types of eucalyptus pro-duction and management in actual investigations.
万方数据
维普
