运用植物地理学方法,结合野外调查及历年文献资料,对内蒙古大兴安岭北部原始林区植物区系组成和地理成分进行统计分析。结果表明:1) 内蒙古大兴安岭北部原始林区共有维管束植物92科373属1 062种(含变种、变型),其中被子植物的科属种分别占维管束植物科属种的84.78%,93.57%,95.76%,在数量上占绝对优势。在科的水平上,单种科和中小型科优势明显,占总科的82.50%;在属种的水平上,含20种以上的较大型科所含的属种数分别占总数的62.61%,68.69%,这些大科在本区植物区系组成中具有明显主导地位。2) 种科比(种/科)指标能较好地反映植物区系的分化强度,本区种科比为12.78。3) 植物区系地理成分多样性,以明显的温带性质为主,其属数占总属数的89.12%,热带分布属占总属数的5.78%,说明本区曾与热带区系有过联系。世界分布属占总属数的16.71%,显示了本区植物的普遍性,特有性程度较低。4) 本区共有国家级重点保护野生植物6种,大兴安岭特有植物3种。

With plant geography methods,combined with field investigation and historical documents,original forest area in north Greater Hinggan mountains in lnner Mongolia,floristic composition and geographical composition were analyzed.The results showed that:1) the Greater Hinggan mountains in lnner Mongolia have the original vascular plants of 92 families,373 genera and 1062 species(including varieties and forms),angiosperms accounted for 84.78%,93.57%,95.76%,of vascudle bundle plants in plots,the absolute advantage in number;in the division level,single section and small and medium-sized obvious advantages,accounting for 82.5% of the total families;on the relation between levels,including more than 20 kinds of larger families,the genera and species respectively accounted for 62.61% of the total 68.69%,these large families in floristic composition in this area has obvious dominance.2)The species/families indexes can well reflect the floristic intensity of differentiation,the kind of family was 12.78.3)Floristic geographical composition diversity with obvious temperate nature is given priority.The number of genera accounts for 89.12% of the total number of genera,genera number of tropical distribution accounts for 5.78% of the total number of genera of tropical distribution,which shows some linkage with tropical flora in this area,genera of the world distribution accounted for 16.71% of the total number of genera.This shows the universality of plants in this area.4) There are a total of 6 kinds of national key protectected wild plants in this area.In the Grester Hinggan Mountains there are three endemic species.