目的 分析预测南方三棘果Emex australis在我国的潜在适生区以及影响其分布的主要环境变量，为防止南方三棘果入侵我国和保护我国农业生产、生态安全提供理论参考。方法 运用刀切法(Jackknife)计算各个环境变量对物种分布的影响。使用ENMeval软件包对MaxEnt生态位模型进行优化处理，将南方三棘果的分布数据和不同气候情景下的气候数据输入优化后的MaxEnt模型，对我国潜在分布区进行预测。结果 最冷季度平均气温(Bio11)对南方三棘果分布影响最大，贡献率为27.7%。环境因子响应曲线表明，最冷季度平均气温为9.35~12.76 ℃时，南方三棘果的存在概率大于0.5；MaxEnt结果表明，南方三棘果在我国的适生区主要集中于云南、广东、广西和福建。结论 对我国南方三棘果适生区应当建立常态化监测方案，在适生区最冷季度平均气温适宜其生存的年份要加大监测力度，防止其在我国定殖、扩散。
Objective The aim of this paper was to analyze and predict the potential suitable regions of Emex australis in China and the major environmental variables affecting its distribution, and provide a theoretical reference for the prevention of the invasion of E. australis into China and protection of the agricultural production and ecological security.Method The Jackknife was used to calculate the influence of each environmental variable on the species distribution. ENMeval was used to optimize the maximum entropy model (MaxEnt). Then the optimized model was used to predict the potential suitable region of E. australis in China by inputting the distribution data of E. australis and the climate data under different climate scenarios. Result The main factor affected the distribution of E. australis was the mean temperature of the coldest month (Bio11), with a contribution rate of 27.7%. The environmental factor response curves showed that the emergence probability of E. australis was greater than 0.5, when the mean temperature of the coldest quarter ranged from 9.35 to 12.76 ℃. Results of the MaxEnt model showed that the suitable regions of E. australis in China were mainly in Yunnan, Guangdong, Guangxi and Fujian. Conclusion A normalized monitoring scheme should be established for the suitable area of E. australis. In the years when the mean temperature of the coldest quarter in the suitable region is good for its survival, monitoring efforts should be strengthened to prevent its colonization and distribution in China.