摘要
在野外考察,分类清理和修订的基础上讨论了西藏壳斗科的地理分布。自然分布的西藏壳斗科植物,共3属33种,集中分布于藏东南的河谷地带和喜马拉雅山脉的聂拉木县。印度栲、刺栲、喜马拉雅石栎和西藏石栎是这些地区海拔2000m以下群落建群种;通麦栎、俅江栎和薄片青冈是西藏海拔1800—2500m地段森林植被的建群种;硬叶高山栎类则是海拔2500m以上硬叶常绿阔叶林及高山灌丛植被的建群种。种的区系成分分析表明:西藏壳斗科植物共有7种区系成分。其中以热带印度、喜马拉雅-中南半岛、中国-喜马拉雅和东喜马拉雅特有等3种成分为最丰富。区系成分分析还表明,海拔2000m以下的西藏壳斗科植物主要来源于热带亚洲:海拔2000m以上的种类主要来源于东亚,特别是横断山。本文还讨论了西藏壳斗科发生发展的地史背景,比较了和毗邻地区壳斗科植物区系的关系。
Distribution of Fagaceae from Tibet has been discussed based on field expedition in Tibet and taxonomical research at present paper.There are 3 genera including 33 species of Fagaceae in Tibet,Castanopsis with 7,Lithocarpus 11,Quercus 15(subg.Cyclobalanopsis8).Most of them are concentrated in river gorge area of southeast Tibet particularly, Medog and Nyalam of Himalayas.Castanopsis indica,C. hystrix,C.tribuloides,Lithocarpes collettii and L xizangensis are dominant elements in vegetation of river gorge area altitude below 2000 meter of southeast Tibet and Q.lanata,Q. kiukiangensis and Q. Iamellosa are dominant in the area of southeast Tibet,altitude range from 1800 to 2500 mcters.Above 2500 meters in this area Q.aquifolioides is dominant.Floristic elements analysis are also made at present paper.Beech plants in Tibet are divided into 7 kinds of floristic elements.They are tropical India,Himalaya to Indo-China distribution pattern,Indo-China to west Himalayan distribution pattern,Himalayan to Japan distribution pattern, Sino-Himalayan distribution pattern,endemic to east Himalaya,endemic to Tibet and endemic to China distribution. Among of them,tropical India,Himalaya-Indochina, Sino-Himalayan and endemic to east Himalayan are the most ahundant.Based on floristic elements analysis it can be concluded that the beech plants which distribute below 2000 meters come from tropical Asia and those distribute above 2000 meters come from tropical Asia and those distribution above 2000 meters come mainly from east Asia paticularly Hengduan Mountains.Geological background of Tibet are also discussed.
出处
《云南植物研究》
CSCD
1995年第2期144-152,共9页
Acta Botanica Yunnanica
基金
国家自然科学基金
关键词
山毛榉科
地理分布
西藏
Fagaeeae,Geography distribution, Tibet, Himalayas