Simulation of Potential Suitable Distribution Area of Pinus tabuliformis in Yiluo River Basin Based on MaxEnt Model

MaxEnt model and GIS was used to simulate potential suitable distribution area of Pinus tabuliformis in the Yiluo River Basin, based on 76 samples and 10 environmental variables. The results showed that area under working characteristic curve (AUC) of training and test set was 0.957 and 0.935, meaning that MaxEnt had good simulation accuracy. According to the Jackknife, contribution rate and permutation importance, mean annual precipitation (35%) was the most important variable, followed by soil type (24.8%), altitude (19.9%), seasonal precipitation (9.2%) and seasonal temperature (7.1%). The result demonstrated that the suitable distribution for P. tabuliformis growth was under annual precipitation of 710-850 mm, seasonal precipitation change within70-74 mm, seasonal temperature change within 7.8℃-8.5℃and with the altitude above 1 156 m. P. tabuliformis was actually distributed in the central and southern region of the Yiluo River Basin, with the area 9 074.84 km2, occupying 46.98% of the Basin.