Fig. 1. Receiver operating characteristic (ROC) curve and average test AUC for accuracy analysis of Bufo gargarizan by MaxEnt model under the current situation.
We found that the most suitable habitats were mainly in the midwest and the eastern coastal areas from current distribution of B. gargarizans(Fig.2). The threshold value of MSS method is 0.33, and according to the distribution probability of B. gargarizans, China is divided into four grades: highly suitable habitat (HS, P≥0.75); medium suitable habitat (MS, 0.5≤P<0.75); poorly suitable habitat(PS, threshold≤P<0.5); unsuitable habitat(US, threshold<P≤0), and the areas of these four types of habitats were calculated in Arcgis, as shown in Table 1. Among them, the unsuitable habitat is 7,216,700 square kilometers, accounting for 75.69 percent of Chinese areas.