辽西医巫闾山植物区系组成及分布格局研究

Floristic composition and distribution pattern of Yiwulüshan and other mountains in China

【目的】研究医巫闾山植物区系组成及与其他山地间大尺度植物类群的相互关系及分布格局。【方法】以位于辽西走廊低山丘陵区的医巫闾山植物区系为研究对象,基于植物地理学理论和外业调查,采用植物区系谱、主成分分析、排序及最小生成树、相关分析和聚类分析等方法,研究了医巫闾山植物区系组成,并分析了医巫闾山与其他山地植物区系属的分布格局及相似关系。【结果】(1)医巫闾山有野生维管植物105科374属804种,其中蕨类植物10科12属21种,裸子植物3科5属7种,被子植物92科357属776种。优势科属现象明显,单种属和少种属所占比例较大,表现出一定的古老残遗性。(2)种子植物属的地理成分主要以温带成分为主,占总属数的78.83%,其次为热带成分,占19.22%,温带成分以北温带分布和旧世界温带分布所占比例较高,分别为温带分布总属数的52.07%和17.36%。(3)对医巫闾山等20个山地植物区系的主成分分析表明,前3个主成分的累积贡献率为87.2%,纬度与14个植物区系成分中的13个均呈显著相关,14个植物区系成分与经度的相关性弱于其与纬度的相关性。主成分排序和最小生成树均将20个山地区系分为4个组别,聚类分析基本上与主成分分析结果一致,即医巫闾山与东灵山、雾灵山、努鲁儿虎山等山地植物区系相似关系最为密切。【结论】医巫闾山野生维管植物种类丰富多样,辽东半岛植物区系可划归为华北植物区系,纬度是影响医巫闾山山地植物区系分布格局的主要因子。

【Objective】This study aimed to explore floristic composition,distribution pattern and similarity with other mountain areas at large scale.【Method】The flora composition of Yiwulüshan in Western Liaoning and similarity with other mountain areas were investigated based on plot survey,floristic spectrum,PCA and MST ordination,as well as correlation and cluster analysis.【Result】（1）Vascular plant flora in Yiwulüshan consisted of 804 species in 374 genera and 105 families,among which 21 species were fern plants belonging to 10 families and 12 genera,7species were gymnosperm belonging to 3families and 5genera,and 776 species were angiosperms belonging to 92 families and 357 genera.There existed dominant family and genus.The single-species and few-species genera of angiosperm were rich,indicating relict phe-nomenon.（2）The floristic analysis indicated that 78.83% seed plants distributed in temperate zone,followed by tropical zone（19.22%）.North temperate zone and old world temperate zone contributed to52.07% and 17.36%in temperate zone.（3）The first three principal components accounted for over 87.2%cumulatively.Latitude was strongly correlated with 13 out of the 14 floristic elements.Correlations of floristic elements with longitude were much weaker than those with latitude.Cluster analysis showed that Yiwulushan had large similarity with Donglingshan,Wulingshan and Nuluerhushan at genera level.【Conclusion】Flora of Yiwulüshan in Western Liaoning were rich and could be grouped to North China plain mountainous sub-region.Latitude was the determinate factor of flora taxon distribution pattern.