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1987年特大森林火灾重创后的大兴安岭,当前又面临森林资源危机。1988年与1964年相比,有林地从632万ha减为538万ha,减少15％;森林覆盖率由70％降至64.7％;活立木总蓄积量由7.2亿m~3减至5.8亿m~3,减少18.4％;大面积密林演化成稀疏林;用材林中的过熟林蓄积由4.5亿m~3减至2.7亿m~3;全区8个林业局已有3个局可采蓄积量将枯竭;65个林场已有22个转产或将大幅度减产。15年后整个林区将无木可采。
After the huge forest fire in 1987 hit Daxinganling, it is facing the crisis of forest resources. Compared with 1964 in 1988, the forest area was reduced from 6.32 million ha to 5.38 million ha, a decrease of 15%; the forest coverage rate was reduced from 70% to 64.7%; the total volume of live standing wood was reduced from 720 million to 380 million m ~ 3, a decrease of 18.4%; large-scale jungle evolved into sparse forest; the over-mature forest in the timber forest was reduced from 450 million m ~ 3 to 270 million m ~ 3; The stock will be depleted; 65 farms have been converted 22 or will significantly cut. After 15 years the entire forest area will be woodless recoverable.