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1987年大兴安岭“五·六”特大森林火灾损失惨重,其中火烧枯死木总蓄积约5500万立米,可利用的蓄积约3000万立米,能作为商品材外销的约2300万立米。由于过火林地上存有大量的火烧枯死木及长势衰弱的中、轻度火烧木,为蛀干害虫的发生和为害提供了有利条件。据1987年7月及10月两次调查,已有大黑天牛、云杉小黑天牛、云杉花天牛、落叶松八齿小蠹虫、松十二齿小蠹虫、落叶松黑小蠹、中央星坑小蠹、西伯利亚吉丁虫、针叶树吉丁虫等10余种蛀干害虫侵入危害,受害率20%左右,如不采取相应措
In 1987, the “5.6” large forest fire in Daxinganling County suffered heavy losses. Among them, the total volume of fire-dead wood was about 55 million cubic meters, the available accumulation was about 30 million cubic meters and about 23 million cubic meters was exported as commercial timber. Due to over-fire woodland there is a large number of fire dead wood and the weakening of the medium and light fire wood, for the stem borers and the damage provided the favorable conditions. According to two surveys conducted in July and October 1987, there have been a large black bull, a spruce black bull, a spruce bull, larch Bethune beetle, pine twelve teeth beetles, larch black small Beetle, the Central Star Pitt Beetle, Siberian Jitian, jelly insects and other more than 10 kinds of borers pests damage, the victimization rate of about 20%, if not take appropriate measures