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大花金鸡菊(Coreopsis grandifloraHogg.)被引种后,因具有较强繁殖和适应能力,在我国山东等地区成为入侵物种,对当地植物多样性造成了一定威胁。笔者运用Maxent生态学模型,基于全球海拔变量及19个生物环境变量,结合地理信息系统ArcGIS,对大花金鸡菊在中国的潜在地理分布区做了预测。结果表明,大花金鸡菊在我国的适生范围主要集中在98°~125°E、21.5°~43°N水分充沛、温度适宜的暖温带、亚热带地区。其中,华东、华中大部,即江苏、安徽、上海市、山东等地为大花金鸡菊的集中分布区,为高适生区;西南、华南北部与华东、华中地区相接的区域,以及华北南部邻接华东地区的局部地区为中适生区,西南、华南南部地区则为低适生区;其他地区不适于大花金鸡菊生长。ROC曲线分析表明,Maxent生态位模型预测大花金鸡菊潜在地理分布的训练数据和测试数据的AUC值分别为0.960和0.965,达到了极高的精度。各环境变量重要性的刀切法检验表明,影响大花金鸡菊地理分布的环境变量依次为年均温、年平均降水量和最冷季平均温度。根据Maxent模型预测结果,以及大花金鸡菊的生物学特性和在中国的入侵现状,在我国中东部地区需要采取一定的有效措施对该物种的扩张进行控制。
After being introduced, Coreopsis grandiflora Hogg. Has become an invasive species in Shandong and other regions due to its strong multiplication and adaptability, posing a threat to the local plant diversity. Based on the global elevation model and 19 biological environment variables, combined with GIS of the geographic information system (GIS), the author uses the Maxent ecological model to predict the potential geographical distribution of Echinacea in China. The results showed that the suitable range of Echinacea in China was mainly in the warm temperate and subtropical regions of 98 ° ~ 125 ° E and 21.5 ° ~ 43 ° N with abundant water and moderate temperature. Among them, East China and Central China, most of which are Jiangsu, Anhui, Shanghai and Shandong, are concentrated distribution areas of Echinacea, which are high-adapted areas; areas in southwestern and southern China and East China and Central China, and southern North China Some areas adjacent to East China are moderate-adapted areas, while southwest and South China are low-adapted areas; other areas are not suitable for the growth of large-flower Coreopsis. The ROC curve analysis shows that the Maxent’s niche model predicts the potential geographic distribution of training data and the AUC of the test data for the potential geographical distribution of Populus euphratica at 0.960 and 0.965, respectively, reaching a very high accuracy. The knife cutting test of the importance of environmental variables showed that the environmental variables influencing the geographic distribution of E. bilineata were annual average temperature, annual average precipitation and the coldest season average temperature. According to the forecast results of Maxent model and the biological characteristics of Echinacea and the invasion status in China, it is necessary to take some effective measures to control the expansion of this species in the central and eastern regions of China.