Potential geographic distribution of relict plant Pteroceltis tatarinowii in China under climate change scenarios

Pteroceltis tatarinowii (Pteroceltis: Ulmaceae) is a deciduous tree that has a cultivation history of more than 2000 years in China. As an excellent afforestation tree species and rare and endangered tertiary relic plant, P . tatarinowii has high ecological protection value. Due to the forest destruction caused by predatory logging and natural environmental factors, the population of P . tatarinowii in China has decreased significantly. In this study, the potential geographical distribution of P . tatarinowii in China under climate change was predicted using MaxEnt model and ArcGIS based on 223 effective distribution points of P . tatarinowii and 11 environmental variables. The results showed that: (1) the prediction accuracy of MaxEnt model was extremely high, and the areas under curve (AUC) value of the training data was 0.936; The area of the potential suitable habitat area of P . tatarinowii under current climate condition was 180.84×10 4 km 2 , and mainly located in the central and southeast regions of China. (2) The domain environmental variables affecting the potential geographical distribution of P . tatarinowii were min temperature of coldest month (12.1~22.7°C), isothermality (26.6~35.8), mean diurnal range 6.9~9.3°C and precipitation of wettest month (189.5 ~955.5 mm). (3) In 2050s and 2070s, compared with current (4.19×10 4 km 2 ), the area of highly suitable habitat will increase by 0.2%-0.3% (RCP2.6) and 1.22%-3.84% (RCP8.5) respectively. while the poorly, moderately and total suitable habitats will decrease. The gravity center of P . tatarinowii showed a trend of migration to higher latitudes and northern regions in the future. These results will provide theoretical basis for cultivation management and resource protection of P . tatarinowii .