基于MaxEnt模型预测西藏红豆杉在西藏的潜在适宜分布区

Identification of Potential Distribution Areas of Taxus wallichiana in Xizang Based on MaxEnt Model

通过MaxEnt模型软件和ArcGIS软件预测西藏红豆杉在西藏的潜在分布范围,用ROC曲线检验预测精度,用刀切法筛选主要环境变量,并通过主要环境变量的响应曲线分析适宜西藏红豆杉的生态环境条件。结果表明,建立的预测模型的AUC值为0.991,预测精度高;西藏红豆杉主要分布于西藏东南区域,自喜马拉雅山脉北麓向东至横断山脉,波密县、巴宜区、墨脱县、察隅县、隆子县、洛扎县、亚东县、定结县、定日县、聂拉木县、吉隆县均有分布,与现地调查结果高度契合;海拔、年降水量、顶层有机碳含量、顶层可交换钠盐等环境因子对西藏红豆杉分布的影响很大。

In this study,MaxEnt model software and ArcGIS software were used to predict the potential distri⁃bution range of Taxus wallichiana in Xizang.The prediction accuracy was tested by ROC curve,and the main environmental variables screened by jackknife test.The ecological environment conditions suitable for Taxus wallichiana were analyzed by the response curve of the main environmental variables.The results showed:the prediction accuracy was high,and the AUC value of the prediction model was 0.991;the distribution range of Taxus wallichiana in Xizang was mainly located in the southeast of Xizang,from the northern foot of the Hima⁃layas to the Hengduan Mountains,it was distributed in Bomi County,Bayi District,Motuo County,Chayu County,Longzi County,Luozha County,Yadong County,Dingjie County,Dingri County,Nyalam County and Jilong County,which were highly consistent with the results of the field investigation;elevation,annual precipitation,organic carbon content of topsoil,exchangeable sodium salt of topsoil and other environmental factors had the great impact on the distribution of Taxus wallichiana.