Study on Spermatophyte Flora of the Alpine Frigid Zone in Shergyla Mountain of Tibet

Scientific survey and identification of plant species indicate that the seed plants are made up of 285 species(which belong to 103 genera and 33 families) in the alpine frigid zone in Shergyla Mountain of Tibet.Among them there are 236 species in 26 families,77 genera of dicotyledons and 4 species(in 1 families,1 genus) of gymnospermae,and 125 species endemic to China.Based on the analysis of the floristic elements from the levels of species,genus and family rank,the results show that:the flora is simple in geographical elements,evident in endemism,and lacking of the ancient and primitive forms in composition.On the analysis of family,genus and species area-types,the component of this flora is basically composed from temperate ones.It shows that the flora is not only of typical temperate character,but also of youthful character,so the flora is a typical alpine frigid one.Owing to the elements in the flora are mainly of Sino-Himalayan ones,so the flora is obviously with plateau and alpine floristic features.