广东中山市薇甘菊地理分布及适生区预测

Geographical Distribution and Suitable Areas Prediction of Mikania micrantha in Zhongshan,Guangdong

通过实地踏查,收集薇甘菊(Mikania micrantha)在广东中山市的分布情况,绘制薇甘菊在中山市的分布图,并利用MaxEnt模型,对薇甘菊实际分布点的环境变量进行定量分析,预测出当前气候下薇甘菊在中山市的适生区。结果表明,中山市所辖25个镇(街道)和市自然保护地管护中心均有薇甘菊分布,总体呈南多北少的态势;ROC曲线的AUC值均在0.8以上,预测结果具有较高的可信度;降水量变化方差、海拔、最冷月份最低温度和最暖季降水量为限制薇甘菊在中山市分布的4个最大环境变量,累积贡献率达75.5%;中山市95.40%的地区对薇甘菊的生长具有不同程度的适宜性,其中高、中、低适生区面积分别占中山市面积的5.33%、33.56%、56.51%。综上所述,薇甘菊对中山市的入侵较为严重,扩散趋势未被遏制;MaxEnt模型能较好地预测薇甘菊在中山市的潜在分布区,但是存在一定偏差。

Through a comprehensive field survey,the distribution points of Mikania micrantha were collected and the distribution map of M.micrantha was drawn in Zhongshan,Guangdong.Meanwhile,the environmental variables of actual distribution points of M.micrantha were quantitatively analyzed by MaxEnt model,predicting the suitable distribution areas of M.micrantha in Zhongshan under the current climate.Results showed that M.micrantha was distributed in all 25 towns(or streets)and Municipal Nature Reserve Management and Protection Center under the jurisdiction of Zhongshan,presenting more in the south and less in the north in general.AUC values of the ROC curve were all above 0.8,suggesting that the predicted results had relatively high credibility.Precipitation seasonality,altitude,minimum temperature of coldest month and precipitation of warmest quarter were main environmental variables that limit the distribution of M.micrantha in Zhongshan,with a cumulative contribution rate of 75.5%.95.40%of the areas in Zhongshan had varying degrees of suitability for the growth of M.micrantha,among which the areas of high,medium and low suitable areas accounted for 5.33%,33.56%,and 56.51%of the areas of Zhongshan,respectively.In summary,M.micrantha invaded Zhongshan seriously,and the spreading trend had not been contained;MaxEnt model could predict the suitable distribution areas of M.micrantha in Zhongshan,but there was a certain deviation.