无量山种子植物区系科属的两种不同排序

TWO KINDS OF DIFFERENT RANKING MATHODS OF FAMILIES AND GENERA OF THE SEED PLANTS FLORA IN MT. WULIANGSHAN

地处滇中南的景东无量山地区迄今计有种子植物２０７科，１０２６属，２５４０种。按照传统的种的绝对数目进行科属的排序可以得到一个较为完整的区系组成，但无法反映这些科属在该地区系建成中的相对重要性。本文提出了区系存在度，即某一科（属）在该地出现的的次级分类群与它的所有次级分类群的比值。按之再去进行排列，可得到一个迥然有异的排序。按绝对种数排序的大科在第二种排序中很少进入，相反，一些东亚特有或与邻近地区共有的科的在此出现的属的相对数目较多，区系存在度就大，能较好地代表该地种子植物区系的特点。同理，对属也进行类似的排列，得到的ＶＦＰ≥５０％的１１３属的排序中，具有１０种以上的大属均未能进入，而东亚及其变型却有３９属（其中中国－喜马拉雅者有２６属），占１１３属的３４．５１％，热带亚洲及其变型有３４属，占３０．９７％，中国特有有２２属，占１９．４７％，其它所有的仅有１７属，占１５．０５％。因此，在无量山的区系中，这三方面的属无疑是具有标志性特点的重要类群。显然，后一种排序能较好地反映什么样的科属在区系建成中的相对重要性来。

There are 2540 species in 1026 genera and 207 families of seed plants in Mt. Wuliangshan which is located in the south central part of Yunnan province, southwest China. We have obtained a complete composition of this flora by ranking of the families and genera according to the absolute numbers of species comprised in them. It is a traditional approach by which it is difficult to reflect the relative importance of such families and genera in its floristic composition. VFP (Value of Floristic Presence), that is, the ratio of the number of the secondary taxa occurring in this place to that in all the world, has been put forward. Then based on VFP arranging them, we can get a rather different rank, in which few large families of absolutely large numbers of species can be found. On the contrary, some small families endemic to East Asia or distributed mainly in it and adjacent regions have higher VFP because of having relatively many genera in this place and can represent the characteristics of this concrete flora. By the same arrangement of the genera, none of the largegenera with more than 10 species can enter the rank of 113 genera with ≥50% of VFP. On the contrary, the genera with East Asia areal type and its subtypes have 39 genera (among them 26 ones belonging to Sino Himalayan subtype) in it, making up 34.51% of the total. The genera with Tropical Asia and its subtypes have 34 ones, doing 30.97%, the ones endemic to China have 22, doing 19.47%, and all the others have only 17, doing 15. 05%. Therefore, in the flora of Mt. Wuliangshan, the three kinds of generaare no doubt important taxa that can symbolize this flora. It is clear that it probably is concluded that the latter ranking can reflect whatfamilies and genera have the relative importance in the construction of this flora.