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檫树为南方速生珍贵用材树种之一。在育苗造林工作中存在不少问题,尤其是育苗密度和苗木质量,各地相差极为悬殊。为此我们试图从生物量和苗木相对生长关系的角度探讨一下适宜的育苗密度和苗木分级标准,于1979年12月在长沙、湘潭、株州、新邵、常德、桃源、溆浦等丘陵地区七个地县共8个苗圃进行了调查、分析。现将结果整理如下,以供参考。一、资料的收集野外调查是根据数理统计的要求,以95%的概率保证,90～95%的精度(苗高为95%,地径为90%)确定调查株数(40～60株),进行机械抽样调查,在现场计算平均苗高、平均
Sassafras tsumu is one of the fast growing timber species in the South. In the nursery afforestation there are many problems, especially nursery density and seedling quality, very different across the disparity. To this end, we try to explore the appropriate nursery density and seedling grading standards from the perspective of the relative growth of biomass and seedlings. In December 1979, in the hilly areas of Changsha, Xiangtan, Zhuzhou, Xinshao, Changde, Taoyuan and Xupu, A total of eight nurseries in seven counties were investigated and analyzed. The results are now organized as follows for reference. I. Collection of Data Field investigation is based on the requirements of mathematical statistics, with the probability of 95% to ensure that the number of surveyed plants (40-60) is 90% to 95% (the height of seedling is 95% and the diameter of ground is 90%), Conduct mechanical sampling survey, calculate the average seedling height in the field, average