大比例尺航片主要测树因子量测分析

THE ANALYSIS OF MAIN TREE MEASURATION FACTORS BY USING LARGE SCALE AERIAL PHOTOS

该项研究采用吉林省长白山林区1:2600比例尺黑白航片,进行主要测树因子量测试验。为解决航片量测与实测结果的可比性,该试验在样地野外每木检尺的同时,划定树木生长级并排序。以航片量测株数为准,取等量实测立木对比(从上层顺取),这样,不仅对比株数相等,对比用的单株也大体在同一范围。并在查明样地被压木数量与航片漏测立木的比率后,根据航片立木漏测规律,编制漏测木蓄积量补偿表,以提高森林蓄积量估测精度。本试验测高精度均方误±1.07m,蓄积量估测精度均方误±6.0m^3。展示了用大比例尺航片量测的实用前景。

B/W aerial photos of the scale 1:2600 were adopted in a test area of Changbeishan Mountain, Jilin Province. Its purpose was to investigate the feasibility of using stereoscopic measurement on air photos to replace some of field work of tree measuration, for the comparision of practical measuration result with that on air photos. The growth classes were divided for the calipered living stocks. And the proportion of suppressed trees that couldn't be identified on the air photos was worked out.The compensation table for the unmeasured trees was established according to the measuration regularity on air photos. The average square error of the experiment on tree height measurement was ±1.07m. The large scale air photos showed a bright practical prospect.