【摘 要】
：
渐伐是在一个较长时期内,分几次伐完整个伐区上全部成熟林木的一种主伐方式。这种主伐方式适用于天然更新容易,林冠下已经有足够的主要树种的幼苗幼树及土壤浅薄的成熟单层
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渐伐是在一个较长时期内,分几次伐完整个伐区上全部成熟林木的一种主伐方式。这种主伐方式适用于天然更新容易,林冠下已经有足够的主要树种的幼苗幼树及土壤浅薄的成熟单层林分。由于这种主伐方式采用伐前更新,作业后不必进行人工更新,能够取得和等带间隔皆伐同等数量的木材,并且在表面上似乎能缩短采育比例失调的距离,
In a long period of time, the downgrade is a method of harvesting all the mature trees on the entire cutting area in a few times. This method of primary harvesting is suitable for natural regeneration easier, under the canopy there are enough of the main tree species seedling saplings and shallow soil layers of mature monolayers. Since this kind of cutting method adopts the pre-cutting updating, it is not necessary to carry out manual updating after the operation, and the same amount of timber can be obtained and cut at the same interval. In the meantime, it seems to shorten the distance of the imbalance of the picking rate,
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