大兴安岭南部(简称岭南)林区次生林林分中,生长缓慢、无培育前途、经济价值较低的残老过熟林、多代萌生阔叶林、灌丛等所占比重较大,约占全林的45%,急待改造、利用与更新,以便使低价林改造成经济价值较高的林分;密度小的改造成密度大的;矮林改造成乔木林;阔叶林改造成针叶 Among the secondary forest in the south of Daxinganling (abbreviation: Lingnan), the proportion of secondary mature forest with slow growth, no cultivating future, low economic value, large multi-generation broad-leaved forest and shrubs account for a large proportion 45% of the forest is in urgent need of transformation, utilization and renewal in order to transform the low-cost forest into higher economic value forest; the transformation of low density to high density; the transformation of the dwarf forest into the arbor forest; the transformation of the broad-leaved forest into the needle leaf