针对立木伐倒后精测材积的现状，以光电经纬仪为主要测量工具,辅以专用软件,形成光电经纬仪测树系统，外业利用光电经纬仪精密的测角功能，配合人工精确量取地径和胸径，内业部分利用专业软件获得树干的胸径、树高和任意处直径，进而计算材积。在对99株中林系列108杨统计分析发现，光电经纬仪精准计测的材积样本均方差σmax=0.1303，σmin=0.0013，各组变量的分布比较集中，离散小，同时CV值偏小，CS绝对值较小，且正偏与负偏相当；同时用407株中395株中林系列107杨的实测材积，建立了二元材积模型，并用12株实测材积进行模型验证，材积最大误差率绝对值为10.1%，最小为2.3%，满足森林计测的误差要求。%For the current situation that the timber volume precision measurement was conducted by the felled standing tree method, the accurate measurement principle and experiment of timber volume by no-felled standing tree method has been carried out. Combining photoelectric theodolite, microcomputer and dedicated software, a tree measuring system was formed. The elevation angles of trees were measured by the photoelectric theodolite, the basal diameter and diameter at breast height of trees were measured through manual, and the diameter at breast height, tree height and diameter at anywhere of trunk were obtained with the dedicated software by indoor operation, then the timber volume was calculated. The statistical analyses on 99 trees (Poplar 108) belonging to Zhonglin Series were conducted, the results showed that the measured mean square errors of volume samples wereσmax=0.1303,σmin=0.0013, the variable distribution of the groups concentrated relatively, the discrete degree were small, Cv value was less than normal, Cs absolute value was smaller, while the positive bias and negative bias is equal;based on the measured volume values of 393 trees of Poplar 107 from 407 trees belonging to Zhonglin Series, a binary volume model was set up. The model was validated with the measured timber volume values of 12 trees, the maximum absolute value of the error rate was 10.1%, the minimum was 2.3%, the error meet the forestry tolerance requirements.
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