南方红豆杉分布区生态适应性分析

为更好地保护南方红豆杉这一重要紫杉醇药用资源，文章利用相关的气候指数，结合国际常用的植被与气候相互关系的指标，对南方红豆杉地理分布区与气候的关系进行了分析。结果表明：1）南方红豆杉各项气候指数的变异系数值均较大，从10.55%到321.08%；2）单一气候指数表明，南方红豆杉分布区温暖湿润，若干气候指标的累计曲线表现出亚热带的特征，其中最明显的特点为年均温大多在15℃以上，且不存在绝水期，雨量充沛；3）综合气候指数中的温暖指数（WI）的最适热量分布范围值（PWH）为107.816，172.504]；4）南方红豆杉分布区的干燥度指数（K）、年均生物温度（BT）和可能蒸发量率（PER）等与其他亚热带物种近似，具有明显的亚热带分布特征；5）主成分分析结果表明年均温度是影响南方红豆杉分布的第一主导因素，最适年均温约为16℃。最后，文章在如何有效保护南方红豆杉和扩大该种群方面提出了一些建议。

Climatic Ecological Adaption for Geographical Distribution of Taxus Wallichiana var. Mairei

For protecting the medical resource of paclitaxel, with the related climate indices, this paper employed the international popular methods about interaction between vegetation and climate to analyse the relationship between geographical distribution of T. wallichiana var. mairei and climate. The authors sampled 306 points within the geographical range of T. wallichiana var. mairei, which mainly come from the references, Chinese Virtual Herbarium (http://www.cvh.org.cn) and National Specimen Information Infrastructure (http://mnh. scu.edu.cn). Climate data mainly come from the software of DIVA-GIS with the World Clim-Goble Climate Data (http://www.worldclim.org/), which can read the information of 19 environment-climate factors such as annual average precipitation, annual average temperature, extreme high and low air temperatures, etc. The relationship between geographical distribution of T. wallichiana var. mairei and climate was analyzed by Kira’s warmth index, coldness index (CI), and Holdridge classification system. The conclusions are as follows: 1) the coefficient of variation (CV)values of the climatic indices range from 10.55% to 321.08%. T. wallichiana var. mairei is widely distributed from subtropical zone to the south temperate zone in China, in the areas of 23°-36° N, 98°-121° E. 2) the annual average temperature in the areas is 16.31℃, but the difference between the extremes is about 20℃; precipitation is another important factor for the distribution, and the annual average precipitation is 1 303.28 mm, precipitation differs in different distribution areas, the highest is 2 645.00 mm and the lowest 535.00 mm, the distribution areas are of subtropical climate, which are characterized by humid and sub-humid features with an average temperature above 15℃ and no obvious dry season. 4) the average aridity index (AI) is 9.44, with the highest 20.48 and the lowest 4.29, meanwhile, the average biological temperature is 16.51℃, higher than the value of subtropical boundary of Chinese vegetation（14℃）but lower than that in Holdridge classification system (＞17℃); annual average evaporation rate (PER)is 0.78, close to that of Cyclobalanopsis glauca which is distributed widely in subtropics. T. wallichiana var. mairei has similar characteristics with other typical species in subtropical zone. 5) Principal component analysis indicates that annual average temperature is the most important factor to affect the distribution, the best temperature is about 16℃. Finally, some effective measures to protect the population are put forward in this paper.