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立地条件是各种因素的综合体,立地潜力通过立地指数来反映。近年来国外多用优势高作为立地指数。1970年以来,优势高亦被引入罗马尼亚的地位级表。文中研究了以下两个问题: 1.确定优势高的正确方式以及优势高的定义。在4个柳林及4个水青冈林的1,878株林木总体内设置样地,测定胸径及树高。为确定优势高的标准,对每个样地分别计算了按径级和全总体平均高的变动系数。计算结果表明,两种平均高的变动系数都较小,全林分的6.7～12.2%,按径阶的3.0～7.8%。平均高的变动系数随径阶的增大而下降,降至(?)+σ径阶左右时趋于常数,不超过3～4%。得出如下结论:从直径大于(?)+σ林木中测得的树高平均值就是优势高((?)为林分平均直径,σ为
Site conditions are a combination of factors and site potential is reflected by the site index. In recent years, foreign high-use advantages as a site index. Since 1970, Dominance has also been introduced into Romania’s status list. The article examines the following two questions: 1. Determine the right way to a high level of superiority and definition of superiority. A total of 1,878 forest trees were planted in 4 Liulin and 4 Fagus plants, and their DBH and tree height were measured. In order to determine the high standard of superiority, the average coefficient of variation for each plot was calculated by the average diameter and the total population. The calculation results show that the two high average coefficient of variation are small, 6.7 ~ 12.2% of the whole forest, 3.0 ~ 7.8% according to the diameter. The average high coefficient of variation declines with increasing diameter, and tends to be constant when it decreases to (?) + Σ, not exceeding 3 to 4%. It is concluded that the mean value of tree height measured from trees with diameter greater than (?) + Σ is superior ((?) Is the mean diameter of the forest, σ is