Hotspots of Chinese Endemic Tree Plant Diversity Under Different Climate and Land Use Scenarios

Climate and land use directly influence species’ spatial distribution, which can alter species’ distribution and lead to significant changes in biodiversity spatial patterns. There are few reports on how climate and land use changes affect plant biodiversity spatial distribution patterns. This study focuses on Chinese endemic tree plants, analyzing the changes in hotspots under current and future conditions (2050 SSP1–2.6 and SSP5–8.5 climate and land use scenarios). Using spatial distribution data of endemic tree plants in China, the Biomod2-integrated species distribution model, and the “top 5% diversity” hotspot identification method, we examine species richness (SR), functional diversity (FD), and phylogenetic diversity (PD). The results indicate that with changes in climate and land use: (1) significant shifts occur in the spatial distribution patterns of hotspots. Although the number of hotspots identified by different diversity indices varies, fragmentation increases across all scenarios. (2) Hotspots tend to concentrate in low-latitude and high-altitude regions. In future scenarios, the longitudinal position of hotspots is significantly lower, and their elevation is significantly higher compared to the current scenario. (3) The spatial patterns of plant diversity in hotspots also change significantly. The SR and PD patterns show similar distribution trends across different scenarios. Under current conditions, the highest values of SR and PD are found in the eastern mountainous regions, such as the Wuyi Mountains and Nanling Mountains, while in future scenarios, they shift to central and western mountainous areas like the Qinling Mountains and Hengduan Mountains. The FD distribution pattern differs, with its highest values consistently found in southeastern Tibet and the Hengduan Mountains across all scenarios. Thus, climate and land use changes not only alter the spatial distribution of hotspots but also change plant diversity within them. This study provides scientific evidence for regional-scale biodiversity conservation under global change.