气候变化对珙桐分布的潜在影响

分析气候变化对植物分布的影响，对气候变化影响下的生物多样性保护具有重要意义. 利用分类和回归树 (Classification and Regression Tree，CART)生态位模型，设定A1，A2，B1和B2 4种气候变化情景，模拟分析了气候变化对珙桐(Davidia involucrata Baill)分布的影响. 结果表明:随气候变化，珙桐目前适宜分布范围将减小，但新适宜及总适宜分布范围将扩大；珙桐适宜分布范围在模拟时段呈缩小趋势，在A1情景下减幅最大，B1情景下减幅最小. 气候变化后，由于珙桐目前适宜分布范围的东部、南部、北部、东北部和东南部地区缩小，而新适宜分布范围将主要向我国西部及西南部地区扩展，因此，目前适宜分布范围将被破碎化. 气温变化对珙桐分布范围的影响大于降水量的影响. 

Potential Effects of Climate Change on the Distribution of Dove Trees (Davidia Involucrata Baill) in China

It is crucial to understand the effects of climate change on the distribution of plant species for the conservation of biodiversity. The effects of climate change on the distribution of dove trees (Davidia involucrata Baill) in China were analyzed using the CART (classification and regression tree) niche model under climate change scenarios A1, A2, B1 and B2. The results showed that climate change in China will cause a large decrease in the current suitable distribution region of dove trees, while it will cause an increase in new suitable or total suitable distribution regions of the plant. The suitable distribution region of dove trees will decrease over the period 1991-2100. It will decrease highest under the A1 scenario and lowest under the B1 scenario among the four climate change scenarios A1, A2, B1 and B2. Additionally, following climate change, some regions in the east, south, north, north-east and south-east of the current distribution region of dove trees will reduce, while new expanding distribution regions of the plant will expand towards the west or south-west of its current distribution region. Therefore, the current suitable distribution region of dove trees will be fragmented following climate change. Additionally, the effect of changing the annual mean air temperature in China on the distribution region of dove trees will be higher than that of changing annual precipitation in China.