应用最大熵模型预测不同气候变化情景下西康玉兰潜在地理分布  

Potential Geographical Distribution of Magnolia wilsonii under Different Climate Change Scenarios Using MaxEnt Model

作　　者：宦智群 徐小蓉[2] 朱冬梅 耿兴敏[1] 唐明[2] 圣倩倩 祝遵凌[1] Huan Zhiqun;Xu Xiaorong;Zhu Dongmei;Geng Xingmin;Tang Ming;Sheng Qianqina;Zhu Zunlin(Nanjing Forestry University,Nanjing 210037,P.R.China;Guizhou Normal University)

机构地区：[1]南京林业大学,南京210037 [2]贵州师范大学

出　　处：《东北林业大学学报》2023年第5期98-105,共8页Journal of Northeast Forestry University

基　　金：贵州省科技支撑项目([2020]4Y028),贵州省重大科技专项计划项目(黔科合重大专项字[2019]3001-5),江苏省高校品牌专业建设项目(PPZY2015A063)。

摘　　要：西康玉兰(Magnolia wilsonii(Finet et Gagnep.)Rehd.)是木兰科木兰属植物,具有很好的观赏、药用和科研价值。该种繁殖能力弱,对环境要求苛刻,分布区域狭窄、种群较小,被列为国家Ⅱ级珍稀濒危植物。预测气候变化对西康玉兰分布范围的影响,为西康玉兰的野生资源保存与可持续利用提供科学基础和参考依据。利用ArcGIS软件与最大熵模型(MaxEnt)计算西康玉兰主要气候因子的贡献率及对应不同适生等级的阈值范围,分析西康玉兰在全国范围内的潜在地理分布,并统计主要分布区域的不同等级适生区面积和现阶段分布点的比例,在4种气候情景(RCP2.6、RCP4.5、RCP6.0、RCP8.5)下,预测未来西康玉兰适生区分布范围以及其质心转移的变化。结果表明:MaxEnt模型预测西康玉兰潜在生境分布的特征曲线(ROC)训练集的AUC(ROC曲线下的面积)值为0.972;年均降水量、昼夜温差与年温差比值、湿度最小季度平均气温、最冷月份最低温是影响西康玉兰分布的主要气候因子,其贡献率分别为33.8%、26.7%、14.6%、14.3%。现阶段,西康玉兰的高、中、低适生区集中分布于云贵川三省交界地带,适生区总面积104.52×10^(4)km^(2),其中高适生区占总适生面积的16.62%,现有分布点处于高适生区内的比例为65.11%。未来20~50 a,全球气候变暖将有利于西康玉兰在中国的分布,其适生区分布基本格局不变,适生区总面积增加,但高适生区的东侧与南侧有缩减与破碎化的趋势;现阶段西康玉兰的潜在分布中心位于四川省的西昌市德昌县内,西康玉兰潜在分布中心有向西北部迁移的趋势,将迁移至西昌市的盐源县内。因此,对西康玉兰濒危资源的保护应结合地理分布,制定多样性保护策略(野生资源调查、野外回归的迁地保护、建立保护区、开展繁殖与栽培技术等)。ArcGIS software and the maximum entropy model(MaxEnt)were used to calculate the contribution of the main climatic factors of Magnolia wilsonii(Finet et Gagnep.)Rehd.and the threshold range corresponding to different suitable levels,calculate the area of different fitness areas in the whole country and its main distribution provinces of M.wilsonii,and count the proportion of distribution points at different suitable levels at current.The MaxEnt model predicted the potential habitat distribution accurately,and the AUC value of the ROC training data was 0.972.Annual precipitation,Isothermality,Mean temperature of driest quarter,Min temperature of coldest month were the main climate factors affecting the distribution of M.wilsonii,and the contribution rates were 33.8%,26.7%,14.6%and 14.3%,respectively.The high,middle and low suitable growth regions of M.wilsonii distribute in the border area of Yunnan,Guizhou and Sichuan Province,the total area is about 104.52×10^(5)km^(2),of which the high suitable area accounts for 16.62%and 65.11%of the distribution points are in the high suitable area.In the future 20-50 a,global warming will be conducive to the distribution of M.wilsonii in China,the basic distribution pattern of its suitable areas remain unchanged,and the total suitable area will increase.However,the west and east of high suitable area has the trend of reduction and fragmentation.At present,the potential distribution center of M.wilsonii is located in Dechang County,Xichang City,Sichuan Province(102.07E,27.43N).Its potential distribution center has a tendency to migrate to the northwest and will migrate to Yanyuan County,Xichang City.In the future,the protection of endangered resources of M.wilsonii should be combined with the prediction results of geographical distribution,and formulation of diversified conservation strategies.

关 键 词：西康玉兰 气候变化 最大熵模型 地理分布 质心转移 

分 类 号：Q948.13[生物学—植物学]