滇西北地区濒危植物的多样性、地理格局及其形成机制

滇西北地区是全球濒危植物多样性的热点分布地区之一。此研究以大尺度的濒危物种分布信息为基础，结合数理统计和GIS空间分析的方法，探讨了滇西北地区濒危植物的多样性、地理分布格局及其形成机制。结果表明，滇西北地区拥有濒危植物64种，分属于60属42科；滇西北地区濒危植物的多样性从南到北呈明显递增的趋势（R2=0．17，P〈0．01）；从空间分布宽度来看，81．3％的濒危植物分布范围狭窄，仅在1～2个县（市）域出现。多元逐步回归分析表明，分布范围狭窄的特有植物的多样性可能是解释研究区域内濒危植物多样性分布格局的主导因素（R2=0．58，p〈0．01）。这意味着滇西北地区濒危植物的形成机制可能与其狭窄生境有关。

Species Diversity,Geographic Patterns and Their Underlying Mechanisms of the Threatened Plants in Northwest Yunnan

The Northwest Yunnan is one of the global hotspots of species diversity, geographic patterns and their underlying mecha- nisms of the threatened plants in Northwest Yunnan threatened plants. Based on the large-scale distribution information of the threatened plants, statistic and GIS spatial analysis, we investigated species diversity, geographic patterns and their underlying mechanisms of the threatened plants in Northwest Yunnan. The results showed that the Northwest Yunnan held 64 threatened plant species, subordinated in 60 genus and 42 families. With the increase of latitude, an increasing trend can be observed on the species diversity of threatened plants （R2 =0.17, p〈0.01）. Our results also showed that 81.3% of the threatened plants distribution range was very narrow （only occurred in 1~2 spatial units）. Statistical analysis showed that species diversity of endemic plants may be the dominant factor for the spatial patterns of threatened plant species （R2 = 0.58, p〈0.01）. It may imply that the narrow habitat may be one of the major underlying mechanisms for the patterns of threatened plants in Northwest Yunnan. Therefore, the protection of their narrow habitat was one of the important counter-measures to protect the threatened plants in Northwest Yunnan.