基于MaxEnt模型的毛荚苜蓿在中国的潜在适生区预测

Prediction of potential suitable area of Medicago edgeworthii in China based on MaxEnt model

摘要:

利用ArcGIS软件和MaxEnt模型对当前气候下毛荚苜蓿(Medicago edgeworthii)潜在适生区进行预测。结果表明:模型预测精度结果极高,验证集(test data)和训练集(training data)AUC值分别为0.984、0.978;毛荚苜蓿适生区主要分布在青藏高原和横断山区交汇处,即西藏自治区东南部、四川省西部、云南省西北部等地,适生区总面积为8.2×10⁵ km²,其中高适生面积为5.23×10⁴ km²,中适生区面积为2.13×10⁵ km²,低适生区面积为5.54×10⁵ km²;毛荚苜蓿适宜分布在海拔2 775.49~4 285.53 m、年降水量445.36~970.69 mm、等温性39.87%~46.43%、最干季度平均温度-7.76~4.20 ℃的区域。本研究结果可为毛荚苜蓿在高寒草地推广种植以及苜蓿属抗逆种质资源研究提供基础依据。

Abstract:

ArcGIS software and MaxEnt model were used to predict the potential suitable areas of Medicago edgeworthii in the current climate.The results showed that the prediction accuracy of the model was extremely high,and the AUC values of the test data and training data were 0.984 and 0.978,respectively.The suitable areas of Medicago edgeworthii Sirj were mainly distributed at the intersection of the Qinghai-Tibet Plateau and the Hengduan Mountain area,including the southeast of Tibet,the west of Sichuan,the northwest of Yunnan and other places.The total area of suitable area is 8.29×10⁵ km²,among which the area of high suitable area is 5.23×10⁴ km²,the area of moderate suitable area is 2.13 ×10⁵ km² and the area of low suitable area is 5.54 ×10⁵ km².The optimum distribution of Medicago edgeworthii Sirj in the region was 2 775.49 m~4 285.53 m above sea level,annual precipitation 445.36~970.69 mm,isotherm 39.87%~46.43%,and average temperature of the driest season -7.76~4.20 ℃.The results of this study can provide a basis for the popularization of Medicago edgeworthii in alpine grassland and the research of Medicago.germplasm resources under stress.