基于MaxEnt模型的迎春樱桃潜在适生区预测

Prediction of potential suitable areas of Cerasus discoidea in China based on the MaxEnt model

【目的】基于迎春樱桃(Cerasus discoidea)在当代(1970—2000年)及未来(2050s,2070s)气候变化下(RCP2.6、RCP4.5、RCP8.5)适生区的面积变化研究,预测其潜在适生区为迎春樱桃的种质资源保护与利用提供参考依据。【方法】基于19个气候变量和3个地形因子,结合迎春樱桃现有的52条有效标本记录信息,利用最大熵MaxEnt模型并结合地理信息系统软件(Arc⁃GIS),分析影响迎春樱桃分布的主要因素,预测迎春樱桃的潜在分布区。【结果】当前环境条件下迎春樱桃潜在适生区主要分布于长江中下游地区,影响物种分布的主要气候因子是最干季降水量(bio17)、最冷月最低温(bio6)、季节性温度变化(bio4)和地形因子坡度(slo)。在未来气候(BCC⁃CSM1.1)条件下其适生区总面积呈减少趋势,但是在2050s时期,温室气体中等浓度的排放条件下(RCP4.5),物种总适生区面积出现最大值,为7.49×10^(5) km^(2);而2050s和2070s时期低浓度(RCP2.6)和中等浓度(RCP4.5)温室气体的排放条件下,物种的中度适生区面积保持不变。【结论】迎春樱桃适生分布区主要分布于长江中下游地区,江西、安徽、湖北、江苏与浙江等低山地区为迎春樱桃种质资源分布的核心区域。

【Objective】Based on Cerasus discoidea of contemporary(1970-2000)suitable areas and the adaptive region of the future(2050s,2070s)under climate change(RCP2.6,RCP4.5 and RCP8.5),these results provided a reference for the protection and utilization of C.discoidea germplasm resources.【Method】Based on 19 climate variables and three topographic factors,combined with 52 valid specimens,the maximum entropy(MaxEnt)model and Arc⁃GIS software were used to analyze and predict the main factors and their potential distribution areas of this species.【Result】Under current environmental conditions,the potentially suitable areas for C.discoidea are mainly distributed in the middle and lower reaches of the Yangtze River.The main climatic factors affecting its distribution were precipitation of the driest quarter(bio17),minimum temperature of the coldest month(bio6),temperature seasonality(bio4),and slope(slo).In the future climate(BCC⁃CSM1.1),the total suitable area of species will decreased,however,in the 2050s,under moderate greenhouse gas emission conditions(RCP4.5),the total suitable area of species will reach a maximum of 7.49×10^(5) km^(2).However,under the conditions of low(RCP2.6)and moderate(RCP4.5)greenhouse gas emissions in the 2050s and the 2070s,the moderately suitable areas remained unchanged.【Conclusion】The suitable distribution area of C.discoidea is mainly in the middle and lower reaches of the Yangtze River,and the low mountainous areas of Jiangxi,Anhui,Hubei,Jiangsu and Zhejiang Provinces are the core areas of this germplasm resources distribution.