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红松(Pinus koraiensis)分杈现象出现在原始林的上层林冠中是不足为奇的,但分杈现象出现在20多年生的人工林中,则引起了人们的普遍关注。天然林分杈部位一般都在主干10—20米高处,而人工林的分杈部位多在主干5—7米处。因此,红松人工林的分杈对出材率的影响是很大的。据我们1984年对伊春林区的部分红松人工林林分的抽样调查结果表明,19—29年生的红松人工林的分杈率平均为20%左右,最高达到95%以上,尚未分杈或分杈率仅在5%以下的林分是为数不多的,红松分杈现象十分普遍。对红松分杈原因,近年来林学界曾提出了
It is not surprising that the bifurcation phenomenon of Pinus koraiensis appears in the canopy of the pristine forest. However, the phenomenon of bifurcation appears in the plantation of more than 20 years old, which aroused people’s widespread concern. Natural forest bifurcation sites are generally 10-20 meters in trunk height, and plantation bifurcation more than 5-7 meters in the trunk. Therefore, the bifurcation of Pinus koraiensis plantation on the timber yield is very large. According to our 1984 sampling of the part of Pinus koraiensis plantations in Yichun Forest Region, the average bifurcation rate of Korean pine plantations aged 19-29 was about 20%, up to 95% Few branches or bifurcation rate of only 5% or less of the forest is one of the few, bifurcation of Korean pine is very common. The reasons for bifurcation of Korean pine have in recent years been proposed by forestry scholars