滇西北地区兰科植物多样性的分布格局及其解释

Geographical Pattern of Orchidaceae Diversity in Northwest Yunnan and Its Explanation

目的:兰科植物地理分布格局以及分布中心的探讨对兰科植物资源的保护具有重要意义。方法:我们利用滇西北地区兰科植物的分布信息,结合属、种水平的分布信息进行分析,探讨了该地区兰科植物属、种水平上的离散度以及多样性的分布格局。结果:从分布格局看,滇西北地区兰科植物的物种丰富度随着纬度的升高呈递增趋势,分布中心则集中在腾冲县、中甸县、丽江纳西族自治县、福贡县、贡山独龙族自治县、大理市、漾濞彝族自治县、洱源县、德钦县、维西傈僳族自治县、泸水县。研究结果也表明,属水平上的多样性数据集的离散系数为0.4,而种水平上的多样性数据集的离散系数高达0.77。总体上,随着海拔高差和湿润度的增加,兰科植物的多样性呈递增趋势。结论:滇西北地区兰科植物多样性分布中心及其分布格局可能与生境异质性和湿润度有关。

Objective： To explore geographical pattern and distribution centers of Orchidaceae is very important in protecting the Orchidaceae＇ s resources. Methods： We investigated geographical pattern of species diversity in this area, using distributional information of the Orchidaceae in Northwest Yunnan, and analyzed the dispersion at genus ＆ species levels. Results： Species diversity of the Orchidaceae in- creased with the latitude, and centers of species diversity were mainly observed in the following areas （Tengchong County, Zhongdian County, Lijiang Naxi Autonomous County, Fugong County, Gongshan Du- long Autonomous CountyDali Municipal, Yangbi Yi Autonomous County, Eryuan County, Deqin County Weixi Lisu Autonomous County, Lushui County）. The study also suggested that dispersion coefficient is 0. 4 at the genera level, and 0.77 at the species levels. On the whole, the diversity of Orchidaceae increased with the increase of altitudinal variation and wettability. Conclusions： Geographical pattern of species di- versity in Northwest Yunnan may be related to environmental heterogeneity and moisture index.