Leonurus japonicus Houtt. is a traditional Chinese medicinal plant with high medicinal and edible value. Wild L. japonicus resources have reduced dramatically in recent years. This study predicted the response of distribution range of L. japonicus to climate change in China, which provided scientific basis for the conservation and utilization. In this study, 489 occurrence points of L. japonicus were selected based on GIS technology and spThin package. The default parameters of MaxEnt model were adjusted by using ENMeva1 package of R environment, and the optimized MaxEnt model was used to analyze the distribution of L. japonicus. When the feature combination in the model parameters is hing and the regularization multiplier is 1.5, the MaxEnt model has a higher degree of optimization. With the AUC of 0.830, our model showed a good predictive performance. The results showed that L. japonicus were widely distributed in the current period. The maximum temperature of warmest month, the min temperature of coldest month, the precipitation of wettest month, the precipitation of driest month, and altitude were the main environmental factors affecting the distribution of L. japonicus. Under the three climate change scenarios, the suitable distribution area of L. japonicus will range shift to high latitudes, indicating that the distribution of L. japonicus has a strong response to climate change. The regional change rate is the lowest under the SSP126‐2090s scenario and the highest under the SSP585‐2090s scenario.

Agastache rugosa (Fisch. & C. A. Mey.) Kuntze has been widely studied because of its high medicinal and edible value. Establishing the priority protected area of wild A. rugosa can provide scientific basis for the protection of germplasm resources. In this study, we predicted the potential suitability distribution area of A. rugosa under the current and future climate scenarios with the MaxEnt model, and the dominant climate factors affecting the distribution of A. rugosa were analyzed. Based on the above results, we predicted the priority protected areas of A. rugosa with the Marxan model. The results showed that A. rugosa is mainly distributed in the eastern and central regions of China at present. In future, the suitable area of A. rugosa will increase, otherwise a few areas will shrink back and migrate to the high latitude areas as a whole. Hydrothermal conditions are the main environmental factors affecting the distribution of A. rugosa. The priority protected areas of A. rugosa are mainly distributed in Chongqing, eastern Sichuan, southern Guizhou, western Hunan and Hubei and southwestern Shaanxi, which are basically consistent with the highly suitable areas predicted by Maxent model. The results of this study are of great significance for the protection and rational utilization of species of Agastache.

Elymus dahuricus Turcz (E.dahuricus) is an excellent forage grass with very high economic value and high adaptability.Predicting the potential habitat distribution of E.dahuricus in China can provide solid and scientific theoretical support for the effective utilization of E.dahuricus germplasm resources.In this study, 180 occurrence sites of E.dahuricus and 38 environmental variables were selected, and the optimized Maxent model and ArcGIS V10.8 software were used to simulate and predict the potential distribution areas of E.dahuricus in China for the present (1970–2020),2050s (2041–2060) and 2090s (2081–2100). The results showed that (1) the simulated AUC value of MaxEnt model is 0.850,with high simulation accuracy; (2)Temperature seasonality(bio4),min temperature of coldest month(bio6),precipitation of driest quarter(bio17),precipitation seasonality(bio15),cation exchange capacity of topsoil(t_cec_soil) and altitude(elev) were the main environmental factors affecting the distribution of E.dahuricus; (3)Presently, the suitable habitats were mainly distributed in Xinjiang, Xizang, Gansu, Qinghai, Ningxia, Inner Mongolia, Shanxi, Hebei, Beijing, Liaoning, Chongqing and other provinces.According to our results that the total suitable habitat area will increase under future climate scenarios and the general trend of mass center toward higher latitude.Our results provide wild resource information and theoretical reference for the protection and rational utilization of E.dahuricus.

To predict suitable growing regions for Leonurus japonicus and to provide scientific sopport for the habitat conservation and the exploitation and utilization of germplasm resources under climate change conditions, this study combined niche and priority conservation models to assess the future potential distribution of L. japonicus in China. To this end, distribution points and samples of L. japonicus were gathered through online and field surveys. The Maxent model with optimized parameters was used for predicting the suitable habitats of L. japonicus at different stages, and the Marxan model was used to determine the priority of protected areas. The results showed that the highest temperature in the hottest month, the lowest temperature in the coldest month, the precipitation in the wettest month, the precipitation in the driest month, and altitude were the main environmental factors influencing the distribution of L. japonicus. Under the three climate change scenarios, the centroid of the suitable area of L. japonicus migrated northward, and the migration position tended to expand further northwest. In the future, there would be no significant niche differentiation of L. japonicus; the Marxan results showed that priority protected areas for L. japonicus were in southwestern central China, Lingnan, southern east China, and Guizhou. Overall, the results of this research can provide a strategy for the determination of priority protection areas for Leonurus japonicus in China.