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机构地区:[1]富民县林业技术推广站,云南富民650400 [2]云南省林业科学院,云南昆明650204
出 处:《西部林业科学》2004年第2期34-36,共3页Journal of West China Forestry Science
摘 要:经对保山市蓝桉及富民县直干桉的固定样地观测,结果表明:蓝桉7年生以前材积增长率大于22 3%,7年生以后小于22 3%;7年与8年生投入、产出比接近,分别为1 2 97,1 2 99;木材基本密度变化不大,因此,蓝桉轮伐期定为7年较为合理。直干桉7年生以前材积增长率大于40 1%,7年生以后小于40 1%,但8年生材积增长率仍大于20%,7~8年木材基本密度变化不大,直干桉实生林轮伐期定为8年比较合理。萌芽林轮伐期可提前1~2年。Observation and measuration were conducted on the fixed sample plots of Eucalyptus globulus and E.maidenii to study the proper rotation period of these two species. The results showed that the volume growth ratio of E.globulus before seven years old was higher than 22.3 %,at the eighth year, the input and output were close to each other,12.97 and 12.99 respectively, and there was no significant variation of wood basic density, it was therefore deduced that 7 years rotation was proper for this species. As far as E.maidenii was concerned, the results showed that the volume growth ratio before the seventh year was higher than 40.1 %, and was lower than 40.1 % after the seventh year, and the growth ratio of the eighth year was still higher than 20 %. There was no significant variation between the wood basic density between the seventh year and the eighth year. Eight year was deduced to be the proper rotation period of E.maidenii. As for the coppice forests were considered, the rotation period could be one or two years shorter than the normal forests.
分 类 号:S792.39[农业科学—林木遗传育种]
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