%A LIN Ling-, HONG Shu-Li-, TU Yan-Li-, LUO Jian %T Floristic Characteristics and Species Diversity of the Orchidaceae on Shergyla Mountain, Southeast Xizang, China %0 Journal Article %D 2013 %J Plant Diversity %R 10.7677/ynzwyj201313049 %P 335-342 %V 35 %N 3 %U {https://journal.kib.ac.cn/CN/abstract/article_33157.shtml} %8 2013-05-25 %X

Floristic characteristics and species diversity of the Orchidaceae on Shergyla Mountain, southeast Xizang (Tibet), China, have been investigated. The results are as follows: (1) This mountain harbors one of the richest orchid floras in Xizang, including 35 genera and 67 species. Most of the species are vulnerable or endangered, and some even critically endangered, thus badly needing protection. (2) Species are diverse in their life form, being terrestrial (21 genera and 42 species, accounting for 60.00% of the total genera and 62.69% of the total species), epiphytic (11 genera and 21 species), or saprophytic (4 genera and 4 species). (3) The species number gradually decreases towards increasing elevations, with the terrestrial orchids occurring in all of the six altitudinal belts of the mountain, the epiphytic ones in lower and middle belts, and the saprophytic ones in a narrower belt from 2800 to 3730m. (4) The floristic components, at both generic and specific levels, are rather complicated. At the generic level, the tropical elements are slightly more than the temperate ones, while at the specific level, the temperate elements are predominant, including 43 species, which account for 64.18% of the total. This indicates that the orchid flora of Shergyla Mountain is of a mixed nature, i.e., being both tropical and temperate, and tends to be purely temperate. It is noteworthy that 30 orchid species on this mountain are of an eastern Asian distribution, respectively accounting for 44.78% of the total 67, and 69.77% of the temperate species, and that 20 species among them (accounting for 66.67%) are of a SinoHimalayan distribution, a reflection of the alpine nature of the orchid flora on Shergyla Mountain. The occurrence of 12 orchid species endemic to China on this mountain suggests a relatively young and derived nature of the orchid flora.