桫椤的潜在适生区及其变化

Predicting the potential suitable habitats of Alsophila spinulosa and their changes

桫椤是极为珍贵的孑遗木本蕨类植物。本研究利用Maxent生态位模型研究其全球潜在适生区及其变化,并运用受试者工作特征曲线(ROC)验证了精度,以为其资源的保护、搜寻和引种栽培提供参考。结果表明:桫椤的潜在适生区主要位于亚洲,少量分布于北美洲、中美洲和香草四岛、新西兰、新喀里多尼亚、斐济。当前气候条件下,桫椤的全球适生区总面积为357.1万km^(2),其中,亚洲占88.4%,中国占49.5%。桫椤在中国的高适生区主要分布在云贵高原、四川盆地、岭南和台湾岛。影响桫椤适生区分布的主导因子为最暖季降水量、7月平均降水量、温度季节性和昼夜温差月均值。在SSP12.6气候情景下,2041-2060年,桫椤全球潜在适生区面积预计减少7.8%,2081-2100年预计增加3.2%;在SSP24.5气候情景下,2041-2060和2081-2100年其面积预计分别增加2.9%和7.2%;在SSP58.5气候情景下,2041-2060和2081-2100年其面积预计分别增加3.3%和5.3%。

Alsophila spinulosa is a rare and endangered relict fern species. With the Maxent model, we predicted the global potential suitable habitat and its future changes for A. spinulosa. We evaluated the accuracy of our prediction based on the receiver operating characteristic curve(ROC), in order to provide reference for the protection, detection and cultivation of its resources. The results showed that most potential suitable habitat for A. spinulosa would be in Asia and few in North Ame-rica, Central America, Madagascar, La Réunion, Mauritius, Seychelles, New Zealand, New Caledonia and Fiji. The global potential suitable habitat for A. spinulosa under current climate conditions encompassed 357.1×10^(4)km^(2), with Asia accounting for 88.4% and China for 49.5% of the total. The highly suitable habitat for A. spinulosa in China would be mainly in Yunnan-Guizhou Plateau, Sichuan Basin, south of the Nanling Mountains and Taiwan Island. The critical factors driving the distribution of A. spinulosa would be the precipitation of warmest quarter, July average precipita-tion, temperature seasonality and mean diurnal range. Under the SSP12.6 climate scenario, the global potential suitable habitat for A. spinulosa would decrease by 7.8% from 2041 to 2060, and increase by 3.2% from 2081 to 2100. Under the SSP24.5 climate scenario, it would increase by 2.9% from 2041 to 2060 and by 7.2% from 2081 to 2100. Under the SSP58.5 climate scenario, it would increase by 3.3% from 2041 to 2060 and by 5.3% from 2081 to 2100.