Abstract:  Erigeron philadelphicus, an alien weed originated from North America, has already invaded in Shanghai, Jiangsu, Anhui, and some other places in China, caused harm on local ecosystem and demonstrated huge potential invasiveness. By using MaxEnt model and geographic information system (GIS), this paper analyzed the environmental variables affecting the distribution of E. philadelphicus, and intuitively and quantitatively predicted its potential distribution regions in China. The prediction was verified by the ROC curve, and the results showed that E. philadelphicus had a wide potential distribution range, with the main suitable distribution area in Shanghai, Jiangsu, Zhejiang, Anhui, Henan, Hubei, Hunan and Jiangxi. At present, the actual invasive range of E. philadelphicus was far narrower than its potential maximum invasive range, and likely to be continued to spread. The ROC curve test indicated that the prediction with MaxEnt model had a higher precision, and was credible. Air temperature and precipitation could be the main environmental variables affecting the potential distribution of E. philadelphicus. More attentions should be addressed to the harmfulness of the weed. To eradicate the existing E. philadelphicus populations and to strictly monitor the invasion ofE. philadelphicus to its most suitable distribution area could be the effective measures to prevent and control the further invasion of the alien weed.

Key words: Erigeron philadelphicus, MaxEnt model, niche, potential suitable distribution area