基于优化MaxEnt模型的我国淫羊藿潜在适生区预测研究

Study on Prediction of Potential Suitable Distribution Areas of Epimedium brevicornu Maxim.in China Based on Optimal MaxEnt Model

目的 预测当前气候条件下淫羊藿在我国的潜在适生区,为淫羊藿资源可持续利用及生产规划提供依据。方法 基于经筛选后的267个淫羊藿物种分布数据及8个环境因子,利用R语言kuenm包优化最大熵(MaxEnt)模型参数,分析影响淫羊藿分布的主要环境因子,并预测其潜在分布范围。结果 优化后模型运行结果遗漏率=0.044 8、Akaike信息量准则=6 409.884 5、曲线下面积=0.986,说明模型准确度较高。基于环境因子贡献率与刀切法表明,当前影响淫羊藿分布的关键环境因子主要有7月份平均降水量、2月份平均最高气温、9月份平均降水量、最冷季度降水量、降水量变异系数、温度季节性变化标准差及最暖季度降水量。模拟结果显示,当前气候条件下我国淫羊藿总适生区面积约221.14×10^(4)km^(2),集中分布在我国中部及中南部地区。其中高适生区面积约23.13×10^(4)km^(2),中适生区面积约73.78×10^(4)km^(2),低适生区面积约124.22×10^(4)km^(2)。结论 本研究可为淫羊藿资源人工栽培规划及可持续利用提供参考。

Objective To predict the potential suitable growth areas of Epimedium brevicornu Maxim.under current climate conditions in China;To provide basis for the sustainable utilization of Epimedium brevicornu Maxim.resources and production planning.Methods Based on 267 screened species distribution data of Epimedium brevicornu Maxim.and 8 environmental factors,the MaxEnt parameters were optimized by the R language kuenm package.The main environmental factors that affect the distribution of Epimedium brevicornu Maxim.was analyzed and its potential distribution range was predicted.Results The omission rate of the optimal model operation results was 0.0448,AICc=6409.8845,AUC=0.986,indicating a high accuracy of the model.Based on the contribution rate of environmental factors and the knife cut method,it was indicated that the key environmental factors affecting the current distribution of Epimedium brevicornu Maxim.were mainly the average precipitation in July,the average highest temperature in February,the average precipitation in September,the coldest season precipitation,the coefficient of variation of precipitation, the standard deviation of seasonal temperature changes, and the warmestseason precipitation. The simulation results showed that the total suitable area for Epimedium brevicornu Maxim. inChina under current climate conditions was approximately 221.14×10^(4) km^(2), concentrated in the central and centralsouthern regions of China. The area of the high suitability zone was approximately 23.13×10^(4) km^(2);the area of thesuitable growth zone was approximately 73.78×10^(4) km^(2);the area of low suitability zone was approximately124.22×10^(4) km^(2). Conclusion This study provides a basis and reference for the artificial cultivation planning andsustainable utilization of Epimedium brevicornu Maxim. resources.