摘要
西版纳勐腊县补蚌的龙脑香林是一种东南亚龙脑香林的热带北缘类型。该群落计约800公顷,经调查有维管束植物642种,隶属于122个科,355个属,其中,种子植物占109科340属及622种、亚种和变种。种子植物的分布区类型组成是:热带或主产热带的科占总科数的78.9％;热带分布屑占总屑数的94.1％;热带分布种超过总种数的90％,热带分布属中有42.3％为热带亚洲分布属,而热带分布种中有73.3％为热带亚洲分布及变型的种类。在热带亚洲分布及其变型的种类中,又具体以印度-马来西亚分布居首位,占总种数的28.9％。分布区类型组成表明西双版纳龙脑香林植物区系是热带性质的植物区系,属于热带亚洲区系的一部分,并以印度-马来西亚分布为其核心成分。由于特殊的地理位置,西双版纳地区是许多典型热带植物的分布北界,同时又是几种热带成分的交汇地带,这又使该龙脑香林植物区系带有热带边缘性质和几种地理成分交汇带的特点。
The Dipterocarp forest occuring in the south of Mengla County, Xishuangbanna, is a forest type of tropical rain forest from the northern margin of tropical zone of SE Asia. This forest, covering about 800 hm2, is estimated to consist of 642 species of vascular plant belonging to 355 genera and 122 families, of which seed plants share 622 species of 340 genera of 109 families and ferns shares the others. In this forest, Rubiaceae with 54 species is the largest family in size and other families are arranged in sequance as following: Lauraceae(35 species), Euphorbiaceae(28), Annonaceae (28), Moraceae (25), Orchidaceae (23), Meliaceae (22), Vitaceae (15), Apocynaceae (13) and Fagaceae (12) etc.. Dipterocarpaceae, Guttiferae, Icacinaceae and Myristicaeae etc., though containing a few species separately, show higher importance value index in this forest community. In the floristic composition of this forest the families of tropical and mainly tropical distribution make up 78.9% of total families; the genera of tropical distribuction make up 94.1% of total genera, of which, the genera of tropical Asia make up 42.3% of the total,the genera of pantropics 19.6%, the genera of old world tropics 14% and the genera of tropical Asia to tropical Australia 9.2% etc.. For the compostion of distributional pattern of species, the species of tropical Asia distribution and its subpatterns occupy 73.3% of total species; the species of SW to SE China occupy 8.2% of the total; the species endemic to Yunnan 10.2% and endemic to Xishuangbanna 5.1%. Further more, among the species of tropical Asia distribution and its subpatterns, the species of Indo-Malesia make up 40%, and the species of S Asia to Mainland SE Asia and of Mainland SE Asia to S China make up 30% respectively. Based on the above statistics, it could be evidently concluded that the flora of this forest is a truly tropical flora in nature and belongs to Indo-Malesia floristic area in world floristic division. It is also undoubted that this forest flora has the closest affinity to tropical Asia flora. As Xishuangbanna is located at the northern margin of tropical SE Asia and is a transitional area of true tropics to subtropics, many typical tropical plants reach up their distributional limits here and some truly tropical families and genera such as Dipterocarpaceae, Myristicaceae, Sapotaceae, Guttiferae, Icacinaceae, Pometia, Barringtonia and Nephelium etc. which have rich species in tropical SE Asia, have a few or a single representative in Xishuangbanna. Therefore, this forest flora is endowed with the nature of northern margin of tropical SE Asia and is transitional toward the subtropical flora of S China in certain extent.
出处
《云南植物研究》
CSCD
1993年第3期233-252,共20页
Acta Botanica Yunnanica
基金
国家自然科学基金资助项目
关键词
西双版纳
植物区系
龙脑香料
Xishuangbannai Dipterocarp forest! Floristic composition
