Predicting the impact of climate change on the distribution of rhododendron on the qinghai-xizang plateau using maxent model.

Amid the ongoing trend of global warming, the distribution of habitable areas for Rhododendron is facing significant risks. To investigate the possible spatial distribution of Rhododendron on the Qinghai-Xizang Plateau in light of future global warming scenarios, we employed the Maximum entropy model (MaxEnt model) to map its suitable habitat using geographic distribution data and environmental factors projected for 2050s and 2070s, considering three representative concentration pathway (RCP) scenarios, while identifying the key factors influencing their distribution. The results show that: [1] The area under curve (AUC) values of the five Rhododendron were all greater than 0.98, indicated that the model prediction effect was excellent; [2] Isothermality is the most important environmental factor affecting the distribution of Rhododendron (excluding Rhododendron przewalskii). The most important environmental factor for Rhododendron przewalskii is altitude (alt: 51%), with an optimum range of 2700-3300 m, and Rhododendron trichostomum are affected by altitude (alt 18%), with an optimum range of 3200-3900 m. Rhododendron przewalskii (bio12: 21%) and Rhododendron trichostomum(bio12: 19%) are also affected by annual precipitation, and Rhododendron laudandum(bio12: 6%) is less affected by annual precipitation, The optimal amount of precipitation is 400-500 mm as well as 500-800 mm. Rhododendron przewalskii and Rhododendron trichostomum are suitable for survival in high altitude, semi-arid areas [3]. The suitable areas for survival for Rhododendron przewalskii, Rhododendron trichostomum, Rhododendron hypenanthum, and Rhododendron nyingchiense is expanding, while the suitable areas for survival for Rhododendron laudandum is shrinking [4]. The optimal zone for Rhododendron przewalskii is primarily found in the eastern section of the Qinghai-Xizang Plateau, while suitable areas for survival for the other four Rhododendron species are predominantly located in the southern region of the same plateau. Therefore, these regions will be designated as the primary conservation zones for in-situ preservation. The results of the study provide a basis for the in situ conservation of Rhododendron in response to global warming, relocation conservation, and the construction of nature reserve communities and ecological corridors.