DISTRIBUTIONAL RANGE SHIFTS IN RESPONSE TO CLIMATE CHANGE: A CASE STUDY OF CONIFER SPECIES ENDEMIC TO SOUTHWESTERN CHINA

Climate change is widely expected to influence geographic distribution and range shifts of plant species. Southwestern China, which has been identified as one of the global biodiversity hotspots, is experiencing a warming trend that is well above the global average. Pinus yunnanensis is a mountainous conifer species endemic to southwestern China. However, little is known about its specific responses to future climate change. Here, based on a maximum entropy (MaxEnt) model, we integrated environmental factors, bioclimatic variables, and species occurrence data from extensive field surveys to project the potential suitable habitats of P. yunnanensis for the years 2050 and 2090 under two climate scenarios. According to our projections, P. yunnanensis generally experienced a suitable habitat loss in the coming decades, and there was a clear acceleration of habitat loss with the severity of climate scenarios. Moreover, the suitable habitat of P. yunnanensis showed a slight southward and downslope shift in response to climate change. Our results indicated that temperature-related factors and solar radiation, especially temperature seasonality, lowest temperature in the coldest month, and mean diurnal range, performed better than precipitation and topo-soil factors in explaining species distributional dynamics. In addition, we identified southern Sichuan and north-central Yunnan as long-term refuges for P. yunnanensis under future climate change, while southeastern Tibet should be protected as a priority conservation area. Our results can be used to guide long-term dynamic monitoring and provide a basis for conservation management of this endemic species.