云南昭通北部地区种子植物区系

The Flora of Seed Plants in Northern Zhaotong,Yunnan Province

基于2006年实地采集的4500余号标本,从科、属、种水平对昭通北部地区种子植物区系特征和性质进行了分析。结果表明:(1)该地区种子植物种类丰富,成分复杂,有159科640属1864种。(2)种子植物区系表现出明显的温带性质。北温带分布属127属,泛热带分布属99属,东亚分布属93属,热带亚洲分布属54属,4种类型共占总属数的60.94%,是该区种子植物区系主要来源。(3)该区植物区系较之滇中高原的小百草岭更近于华中植物区系的梵净山,应隶属于中国-日本植物亚区之华中区系,而与云南的大部分地区明显不同。(4)该区有中国特有科1科珙桐科,东亚特有科10科、中国特有属27属、中国特有种1063种,特有种的比例高达57%。丰富的特有成分,表明该区植物区系的古老性和独特性。该区植物区系具有深刻的热带亚洲的历史背景,而现代植物区系总体上已经是东亚植物区系中的华中植物区系性质。

Northern Zhaotong is located at the intersection of Yunnan, Guizhou and Sichuan Provinces, where floristic study was rarely dealt with. Based on over 4 500 specimens collected from this area in 2006, the floristic characteristics at the levels of family, genus and species were analyzed for the first time. The results showed that： 1） There were totally 1 864 species of seed plants belonging to 640 genera and 159 families, indicating that the flora is rich in species and diverse in geographical elements. 2） The flora showed an obvious temperate feature. There were 127 genera of North Temperate elements, 99 genera of pantropic elements, 93 genera of East Asian elements and 54 genera of Tropical Asian elements. These four distribution types, which stood for 60.94% of the total number of genera, are the main components of the flora. 3） The flora was more similar to that of Fanjingshan Mountain, belonging to the Central China Region, than to that of Xiaobaicaoling （loeated at central Yunnan Plateau）, and belongs to the Central China Region of Sino-Japan Forest Subkingdom. 4） There are 10 families endemic to East Asia, 1 family endemic to China, 27 genera endemic to China, 1 063 species endemic to China （accounted for 57% of the total species）. The abundant endemic elements indicated that the flora is ancient and unique. It is suggested that the flora, with a deep tropical Asian historical background, is a part of the Central China flora.