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瑞典的森林面积占国土面积的1/2以上,达2,400万公顷。国有林仅占森林总面积的18%,主要分布在山区及北部。瑞典的森林经理调查是利用航空照片进行的。比例尺为1:15000-1:20000。这种照片是利用六万分之一的航摄底片放大制成的。航空照片的主要作用是绘制草图,判读边界,划分调查小班。林分的全部测树因子均在林内调查,但是在调查中调查员不仅要确定他们亲眼见到的调查小班的各项测树因子,而且还要根据对航空照片的分析,确定所有小班的测树因子。为此,他们直接在林内用手提式
Sweden’s forest area accounts for more than one half of the country’s land area, reaching 24 million hectares. State-owned forest accounts for only 18% of the total forest area, mainly in the mountains and the north. A survey of forest managers in Sweden took place using aerial photographs. The scale is 1: 15000-1: 20000. This picture is made using one-six thousandth aerial camera zoom made. The main function of aerial photos is to draw sketches, read the boundaries, and divide the survey into smaller classes. All the tree measures of the stand are in the forest survey, but during the investigation, the investigators not only need to determine the tree-finding factors of the survey small class that they have witnessed, but also make sure all small class measurements based on the analysis of aerial photographs Tree factor. For this reason, they use hand-helds directly in the forest