辽宁努鲁儿虎山国家级自然保护区植物区系及地理成分研究

运用植物地理学方法，结合野外实地调查及相关文献资料，对辽宁努鲁儿虎山国家级自然保护区植物区系组成和地理成分进行了统计分析。结果表明:该保护区共有维管植物97科412属1 006种，其中被子植物在科、属和种的水平上分别占到区域植物总数的866%、95.3%和95.5%，在数量上占绝对优势；在科的水平上，寡种科和中型科优势明显，占总科的73.2%；在属、种的水平上，含20种以上的较大型科所含的属和种数分别占总数的51.3%和56.2%，在植物区系组成中具有明显的主导地位。种科比（种/科）指标能较好地反映植物区系的分化强度，该保护区种科比为10.37，与同纬度其他地区相比，分化强度高，说明该区特有的地理位置及气候条件对植物多样性具有重要影响。植物区系地理成分多样，以明显的温带性质为主，其属数占总属数的80.29%，同时与热带植物区系也存在一定的亲缘关系，其属数占总属数的19.71%。世界分布属占有较高比例（13.53%），远高于全国该类型所占比例的3.34%，由此表明该植物区系及地理成分具有高度的过渡性。 

Composition and geographic elements of the flora in Nuluer Hushan National Nature Reserve, Liaoning of northeastern China

This paper studies the composition and geographic elements of flora in Nuluer Hushan National Nature Reserve of Liaoning Province,northeastern China by applying the methods of phytogeography,and based on field plant investigation and the relevant literatures.The results showed that there were 1 006 vascular plant species,belonging to 412 genera and 97 families,among which angiosperms play the leading role and accounted for 86.6%,95.3% and 95.5% of all the families,genera and species,respectively.At family level,the single-species families and middle-size families were the main part of the local flora,which accounted for 73.2% of all families;At genus and species levels,over 20 species families were the main part of the local flora,which accounted for 51.3% and 56.2% of all genera and species,respectively.The ratio of species to family could indicate the degree of floral differentiation,which was 10.37 in this nature reserve,and greater than other areas of the same latitudes,representing the higher level of flora differentiation.The flora showed the composition of temperate zone remarkably,temperate genera accounted for 80.29% of all genera,although there was a certain relationship with the flora of tropic zone,and tropic genera accounted for 19.71% of all genera.Meanwhile,cosmopolitan genera accounted for a considerable proportion(13.53%),which was far above the countrywide level (3.34%),showing that the local flora is vulnerable and transitive of geographic element.