Paeonia decomposita (P. decomposita) belongs to the peony group of woody plants and can be used to cultivate new peony varieties and as traditional Chinese medicinal medicine. With the increasing demand for P. decomposita in the herbal market, it is endangered and in urgent need of conservation. In this study, the potential distribution area of P. decomposita was simulated by the Maxent model. The environmental factors affecting the distribution of P. decomposita were analyzed by applying the environmental factor contribution rate and knife-cut test, respectively.
The results showed that the AUC value of the P. decomposita training set data was 0.949, indicating that the model was accurate. Currently, P. decomposita’s highly suitable areas are mainly distributed in Ganzi and Aba Prefectures in a strip-like manner, and the other part is sporadically distributed in Diqing Tibetan Autonomous Prefecture and Changdu City, with an area of 1.56×104 km2, accounting for 7.10% of the total suitable areas, and the most important environmental factor for its geographic distribution is the altitude. Under the backdrop of future climate change, the areas of suitable P. decomposita all showed an increasing trend. Among them, high and medium suitable areas showed a significant increase in area and were strongly affected by climate change. P. decomposita’s highly suitable areas migrated in different latitudes and directions, and the migration span was larger under the high-concentration emission scenario. This study provides a scientific basis for the promotion, cultivation, and conservation of P. decomposita by predicting its potential geographic distribution and clarifying its ecological requirements.