高黎贡山北段种子植物区系研究

高黎贡山北段种子植物种类十分丰富,共记载野生种子植物172科,778属,2514种及302变种(亚种),是植物多样性最为丰富的地区之一。区系成分分析表明:1)本区种子植物区系的性质具有鲜明的温带性,并深受热带植物区系的影响,区系地理成分复杂、联系广泛;2)现代种子植物区系是在古南大陆热带亚洲植物区系的基础上,由古南大陆成分及古北大陆成分在漫长的地质历史过程中融合发展而来,许多源于印度-马来、北温带(特别是东亚)的成分在此都产生了较为丰富的特有类群,它们共同演变成今天的植物区系外貌;3)种子植物区系具有明显的水平和垂直替代现象,间断现象也较为显著,主要表现为滇西北-滇东南间断分布或在此线西南侧连续分布;4)种子植物区系的特有现象十分丰富,物种分化强烈,新老兼备,而以新生的进化成分为主,由此表明高黎贡山北段在保存古老成分的同时,又分化出许多新生成分,它是一个孕育新特有现象的重要舞台。

A Floristic Study on the Seed Plants of the Northern Gaoligong Mountains in Western Yunnan, China

The northern Gaoligong Mountains is rich in species and it is one of the richest areas of plant diversity in the world. So far, 2 514 native species and 302 varieties (or subspecies) belonging to 778 genera in 172 families were recorded. Based on the statistics and analysis of families, genera, and species, a floristic study on the seed plants of the northern Gaoligong Mountains was carried out. The results are as follows: 1) The main floristic feature is temperate, but it is greatly influenced by tropical elements. The floristic relationships are complex, and many kinds of distribution types are represented here; 2) During the long geological history, the process of fusion and development among Gondwanaland and Laurasia floras is a key to the origin of modern flora of the northern Gaoligong Mountains. In addition, some elements that came from Indo-Malaysia and North Temperate (especial Eastern Asia) differentiated into variously rich endemic taxa in the region. Based on the tropical Asian flora, all of the endemic taxa and the two elements mentioned above together changed into the framework of the present flora during geological time; 3) The horizontal and vertical vicariance of the flora is evident in the northern Gaoligong Mountains.The disjunct distribution is also evident,the main disjunct type is a distribution pattern from northwest to southeast Yunnan or only distribution in the southwest of the line that along from northwest to southeast Yunnan; 4) The endemism within the flora is rich and the endemic elements differentiated strongly in the region.The palaeoendemic and neoendemic elements can co-exist in the region,but the neoendemic elements are dominant.These data show that northern Gaoligong Mountains not only is a refuge for some ancient floristic elements but also is a differentiation center for some new floristic elements.