Abstract:Coelonema draboides is an endangered plant endemic to the Qilian Mountains. Prediction of potential suitable areas of C. draboides can provide important reference for conservation and research of C. draboides. Based on geographical distribution records and environmental factor variables, we used MaxEnt and ArcGIS models to simulate the suitable distribution areas of C. draboides in the Qilian Mountains under three climate scenarios, namely the present and future (2050s, 2070s) RCP2.6, RCP4.5 and RCP8.5, using 41 effective distribution points and 28 environmental factors. The leading factors affecting the distribution were screened. The results show that: (1) the mean value of AUC of training data sets is 0.948, and the mean value of random error is 0.043, so the MaxEnt model has a high simulation prediction accuracy. (2) The main factors affecting the geographical distribution of C. draboides were altitude, diurnal range of average temperature, isotherm, precipitation in the wettest month and soil organic matter, which accounted for 87.4% of the total contribution rate. (3) When the altitude is 3 000-4 000 m, the average daily temperature range is 10-12 ℃, the isotherm is 32-35, the precipitation in the wettest month is 140-160 mm, the soil organic matter is 1.2%-1.5%, and the annual average temperature is 0-25 ℃, it is suitable for the growth of C. draboides. It is speculated that C. draboides is suitable for growing in low heat, large daily temperature difference and small annual temperature difference, cold and semihumid plateau climate. (4) Under the current climate conditions, the potential geographical distribution of C. draboides was mainly located in the eastern and southern parts of Qilian Mountains. With the change of climate and time, the potential suitable area of C. draboides decreased, and the highly suitable area in the southern part of Qilian Mountains shrank to the north, and most of them were concentrated in the Qilian Mountain protection area. (5) In the future, it can be considered to focus on protecting the species in the Qilian Mountains Reserve, and the southern part of the Qilian Mountains Reserve can be used as a protected area for in situ protection.
