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前言森林调查中,面积统计工作,特别是商品材林地面积,并把它分为不同森林类型和条件级的面积的统计是主要目的之一。照片与地面联合的抽样方法可以降低森林调查的费用。但如何安排照片地面工作,使单位费用得到最精确的资料,这一方面过去没有足够的分析材料,一般文献都偏重于蓄积量估测方面。现在,关于不同抽样方案对于面积统计上的相对效率一
Foreword In the forest surveys, the statistics of area, in particular the area of forest of commercial timber, and dividing it into statistics on the area of different forest types and conditions are one of the main purposes. Joint sampling and ground-based sampling methods can reduce the cost of forest surveys. However, how to arrange the work of photos on the ground to get the most accurate information on the unit cost has not been enough in the past to analyze the materials. Generally, the literature focuses on the stock volume estimation. Now, on the relative efficiency of different sampling plans for area statistics