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一、实验的目的在大面积的森林抽样调查中,尤其是在交通不便的原始林区和山高涧深的南方林区,系统抽样样点间距过大,往往使消耗在样点间途中的时间远远超过样地测设、调查的时间,无形中降低了系统抽样调查的工作效率。为了提高工效,在系统抽样每个点位按预定的组合方式设置一群样地,以群为抽取单位,对群中的每个样地进行调查,从而完成对总体的估计,这种方法,就是所谓成群抽样调查。本次成群抽样实验的目的是:
First, the purpose of the experiment In a large area of forest sampling survey, especially in the poor traffic of the original forest area and the mountain forest depths of the southern forest, the sampling interval sampling system is too large, often consumed in the sample time on the way between Far beyond the plot test, survey time, virtually reduced the efficiency of the system sampling survey. In order to improve ergonomics, a group of plots are set according to a predetermined combination at each sampling point of the system, and each sample in the cluster is surveyed by taking a group as a sampling unit to complete the estimation of the population. That is, The so-called clustered sample survey. The purpose of this cluster sampling experiment is: