Abstract:

In order to provide a theoretical basis for scientific protection and utilization of Dracocephalum L., the dominant environmental factors that limit the survivability of Dracocephalum L. were discussed and the potential distribution areas of them under different climatic environments were simulated. Based on the information of geographical distribution and environmental factors of Dracocephalum tanguticum and Dracocephalum heterophyllum which have highly medicinal value, the dominant environmental factors were analyzed by the MaxEnt model of these two species, and the suitable growth areas for them under current and future climate were predicted. The results showed that altitude was the key environmental factor affecting the distribution of the two species, with the contribution rates of 51.4% and 73.7%, respectively. The most suitable ranges for the distribution of the two species were 3028.63~4414.68 m and 2940.13~4703.83 m. The percentages of the suitable areas of the two species were 10.27% and 26.57% in China under current climate environment, and the medium-high suitable area were mainly distributed in Tibet, Qinghai, Gansu, Sichuan and other provinces. It was predicted that the distribution of the two species would migrate to the high-altitude areas in the future, and the highly suitable areas would still be mainly around the Himalayas, Qinghai Lake, and the mountainous zone of junction of Tibet, Qinghai, and Sichuan provinces. Therefore, the prediction of the effects of climate change on the distribution of the two species of Dracocephalum L. is helpful to provide reference for the division of plant reserve and the selection of artificial planting sites in the future, so as to protect plant germplasm resources and achieve the purpose of sustainable development.

Key words: Dracocephalum tanguticum, Dracocephalum heterophyllum, MaxEnt model, the potential distribution, climate change