未来气候变化对广布种麻栎地理分布的影响和主导气候因子分析

Effect of Climate Change in Future on Geographical Distribution of Widespread Quercus acutissima and Analysis of Dominant Climatic Factors

摘要:

为了解麻栎（Quercus acutissima）的潜在分布特征及其对未来气候的响应，运用最大熵模型（Maxent）模拟在当前气候条件下麻栎的潜在分布格局，预测未来不同温室气体排放情景下的格局变化，并分析影响其分布的主导因子。结果表明，Maxent模型有较好的预测能力，AUC值大于0.95。当前气候条件下，麻栎广泛分布于我国南方大部分地区和陕西、河南、山西、甘肃、北京、辽宁等北方省市。此外，在日本、朝鲜半岛、老挝、越南、缅甸、尼泊尔、不丹、印度、巴基斯坦等国家和地区亦存在不同程度和范围的麻栎适生区域，麻栎总适生区域面积达11.57×10⁵km²。在RCP2.6和RCP8.5情景下，麻栎适宜分布区域向北和西南方向扩展，新增适生区面积为（2.49~3.02）×10⁵km²；适生区域丧失主要集中在广西南部、广东南部和缅甸东部等地。影响其分布的主导气候因子为最暖季降水量、等温性、最干季均温、最冷月最低温，因子贡献率分别为54.2%、13.7%、8.8%和7.8%。这为麻栎的栽培和保育研究提供了参考依据。

Abstract:

To understand the potential distribution characteristics of Quercus acutissima and its response to future climatic change, the Maxent model was used to simulate potential distribution under present climatic condition, and predict changes in its distribution under different greenhouse gas emission scenarios in future, and major factors affecting its distribution were analyzed. The results showed that Maxent had relatively good predicting ability for the distribution of Q. acutissima with AUC value more than 0.95. Under the current climatic condition, Q. acutissima could be widely distributed in southern China and some provinces of northern China, such as Shannxi, Henan, Shanxi, Gansu, Beijing and Liaoning, as well as Japan, Korea peninsula, Laos, Vietnam, Myanmar, Nepal, Bhutan, India, Pakistan, with a total suitable area about 11.57×10⁵km². Under future climate scenarios of RCP2.6 and RCP8.5, the suitable area of Q. acutissima predicted by Maxent model will expand northward and southwestward, increasing ca. (2.49~3.02)×10⁵km²;the loss of suitable area mainly occurred in southern Guangdong and Guangxi Provinces and eastern Myanmar. The dominant factors influencing the distribution of Q. acutissima were precipitation of the warmest quarter, isothermality, minimum temperature of the coldest month, mean temperature of the driest quarter, with contribution rates of 54.2%, 13.7%, 8.8%, 7.8%, respectively. These would provide a reference for studying the cultivation and conservation of Q. acutissima.