Relationships between Geographical Distribution of Taxus wallichiana and Climate in China

According to the data on geographical distribution of Taxus wallichiana Cheng et L.K.Fu,several indexes widely used for the study of vegetation-climate interaction were applied.These indexes included Kira's warmth index and coldness index,Xu's humidity index,Penman's formula,Thornthwaite's indexes and climate classification,Holdridge's life zone classification system,annual average temperature,mean temperature in January,mean temperature in July,maximum temperature,minimum temperature,≥10 ℃ accumulated temperature and precipitation.The relationship between the distribution of T.wallichiana and climate in China was analized and the Kira's water-temperature indexes on distributional upper limit,lower limit and north limit were discussed.The principal component analysis showed that relative effect of climate indexes on the distribution of T.wallichiana followed the order thermal factor in coldness month relative humidity thermal factor in hotness month accumulated sunshine time.