三棱栎群落的区系成分初步研究

A PRELIMINARY STUDY OIN THE FLORISTIC ELEMENTS OF THE COMMUNITY OF FORMANODENDRON DOICHANGENSIS

根据三棱栎［Ｆｏｒｍａｎｏｄｅｎｄｒｏｎｄｏｉｃｈａｎｇｅｎｓｉｓ（Ｃａｍｕｓ）Ｎｉｘｏｎ＆Ｃｒｅｐｅｔ］群落的野外调查结果，分析了该群落的区系成分。热带及亚热带区系成分占很大比重（占总种数９０．２５％），其中印度－马来西亚成分占有绝对优势（占４１．４６％），滇、缅、老、泰、越周边地区的区系成分次之（共占２９．２７％），与热带非洲有微弱联系，但与热带大洋洲与热带美洲并无联系。这就在该群落区系成分分析的基础上有力地支持ＫｅｖｉｎＣ．Ｎｉｘｏｎ和ＷｉｌｌｉａｍＬ．Ｃｒｅｐｅｔ的论点：三棱栎是独立的属，而三棱栎是在早第三纪时起源于Ｔｒｉｇｏｎｏｂａｌａｎｕｓｖｅｒｔｉｃｉｌｌａｔａ的祖先类型。

According to the result of wild survey on the FOrmanodendron doichangensis-commu-nity, the floristic elements of the communitv has been analysed.The Tropical & Subtropical floristic elements are of a great deal(90.25 % of the total species),amcog them the Indo-Malaysian floristic elements are in the frist place(41.46%),the floristic elements of the bor-der land in Yuaana and other countries(Burma,Laos,Thailand and Vietnam)are in the second place(292% in total),the floristic elements relating to TropicaI Africa are few, but there are no the floristic elements relating to Tropical Australia or Tropical America. Based on the floristic analysis of the community,it is strong to support the view suggested by Kevin C. Nixon & William L. Crepet:Formanodendron is a distinct genus and F.dOichangensis was originated from the ancestor of Trlkonobalanus verticillata in early Tertiary.