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目前我国林业调查技术,已由目测调查,发展到以数理统计学为基础的抽样调查。但林业求积技术仍没有达到应有的统一和严格要求。大部分地区对样地求积多采用一元材积表。然而,我国森林面积大,分布广,树种多,测树用表少,故不能全面满足生产需要,且各地对各树种的测树用表,在制法上,精度要求上,都不统一。过去材积表的原始材料,大部分不是随机样本。有些地方在材积表的使用上,严格检查校正也注意不够。在把二元材积表导成一元材积表时,对样地测高的精度,要求不严。目前,在资源调查中,当计算总资源精度时,往往由于这些实际存在的问题,而造成的误差,都没有计算在内,显然这就不够严密。因此,在推广抽样调查的同时,注意改进林木求积技术,是非常必要的。
At present, China’s forestry survey technology has been developed from visual inspection to sampling based on mathematical statistics. However, the technique of cross-plotting forestry still fails to meet the unification and strict requirements that it should have. In most areas, plots of plots are used for quadrats. However, China’s forest area is large, widely distributed, there are many tree species, and there are few measuring tables. Therefore, the production needs can not be fully met and the tree-measuring tables of various tree species are used all over the country. Most of the original material from the volume chart was not a random sample. In some places in the use of volume chart, strict inspection and correction also not enough attention. In the binary volume table lead into a single volume table, the accuracy of the elevation of the plot, the lax requirements. At present, in resource surveys, when calculating the total resource accuracy, the errors often caused by these actual problems are not taken into account. Obviously, this is not strict enough. Therefore, it is necessary to pay attention to improving the technology of forest quadrats while promoting the sampling survey.