Dipteronia sinensis is an endangered relict tree species in the endemic north temperate flora of China, which has important reference values for studying paleoclimate and species variation as well as geographic zonation changes. Based on 96 occurrence points of D. sinensis and 9 environmental factors, the potential geographic distribution of D. sinensis in China under climate change was predicted using MaxEnt model and ArcGIS software, the Jackknife test was used to assess the important factors governing its potential geographic distribution. In addition, response curves were selected to determine the suitable values of environmental factors and further quantitatively predicted the potential geographic distribution of D. sinensis under the climate changet. The results showed that: (1) the prediction accuracy of the MaxEnt model was extremely high, with an area under receiver operating characteristic curve (AUC training value) of 0.959. The potential suitable habitat area of D. sinensis under current climate condition was 103.9 × 104 km2, mainly located in the central and northwestern regions of China; (2) the main environmental factors affecting the potential geographic distribution of D. sinensis were the temperature factor (min temperature of coldest month) and the precipitation factor (annual precipitation); (3) the area of low, high and total suitable habitats showed a decreasing trend under SSP1-2.6 and SSP5-8.5 scenarios in 2070s, and the area of moderately suitable habitats showed an increasing trend under the three scenarios in 2050s and 2070s, and the center of gravity of the potential suitable habitats of D. sinensis would shift to the northwest. Our results can provide a theoretical basis for the scientific management and resource conservation of D. sinensis.

Cupressus funebris Endl. (C. funebris) is an evergreen tree endemic to China that is classified as a national second-class endangered plant. This species plays critical roles in soil and humidity conservation, climate regulation, and ecological restoration. It is also important in silvicultural production, which is crucial for maintaining the stability of the ecosystem in Southwest China. In this study, an integrated modeling approach was used to integrate 10 species distribution models to simulate the potential distribution of C. funebris and predict the impact of future climate change on its distribution and ecological niche. Field surveys were conducted to compare the forest stands of C. funebris under different habitat suitability levels. The results showed that the most suitable areas for C. funebris were mainly located in Sichuan, Chongqing, and Guizhou, covering an area of approximately 15.651 × 10⁴ km². The productivity of the C. funebris forest stands in these highly suitable areas and was significantly higher than that in low and moderately suitable areas, although understory plant diversity did not show a competitive advantage. Under future climate scenarios, the potential distribution of C. funebris in China will expand and the geographical range of the niche will shift to higher latitudes in northern China as temperatures increase. The extent of this change in the niche’s geographical range intensified as warming increased. Specifically, under the 2090s-SSP585 climate scenario, the highly suitable area for C. funebris is projected to double, suggesting a significant expansion of the geographical range of the niche under this climate model, with more than half of the niche experiencing separation. In summary, the potential distribution of C. funebris may continue to expand and shift to higher latitudes in the context of global warming and its ecological niche’s geographical range will be adjusted accordingly. These findings provide a theoretical basis and practical guidance for in situ conservation, ex situ conservation, and rational utilization of C. funebris genetic resources by conducting niche modeling and climate suitability assessments.

Changes in future climate will have a great impact on biodiversity. Magnolia wilsonii, an endangered tree native to China, has important scientific and medicinal value occurring in western Sichuan, northern Yunnan and western Guizhou. And it has severely declined and become critically endangered in the last years due to habitat loss and fragmentation. In this study, we modeled the current and future distributions of M. wilsonii under three representative concentration pathways (SSP1-2.6, SSP2-4.5 and SSP5-8.5). The results showed that the AUC values of all simulations were greater than 0.940. The key environmental variables affecting the potential distribution of M. wilsonii were the annual precipitation (573-1671 mm), the min temperature of coldest month (10.1ºC-16.2ºC), the coefficient of variation in precipitation seasonality (11.5-160.9), and the standard deviation of temperature seasonality (404.7- 1765.6). The area of the highly suitable habitat was 29.66×104 km², mainly concentrated in Yunnan, Sichuan, Guizhou and Guangxi. Yunnan had the largest suitable habitat, occupying 13.23×104 km², accounting for 44.6% of the highly suitable area. Under the three climate change scenarios, the areas of the suitable habitat of M. wilsonii showed increasing trends, the geometric center of the highly suitable habitat would move to the northeast. Our results can provide a scientific basis for the protection, cultivation, management and sustainable use of M. wilsonii.

This study focused on assessing the impact of climate change on Cupressus funebris, one of the important endemic conifer species in China. The impact of fluctuations in temperature on the potential distribution and extinction risk of the C. funebris was evaluated using species distribution modelling. The outcomes of this current study revealed that the species was mainly distributed in mountainous forest areas, and climate variables played a major role in the distribution of this conifer tree. Under climate change, the threatened conifer will be mainly concentrated in mountainous forests and is projected to undergo contraction in distribution and shift northward. The conservation status of C. funebris is projected to be uplisted to “Near Threatened” status under the SSP5_8.5 scenario by 2040 and to the “Least Concern” status under all the other investigated climate and dispersal scenarios. Despite the high capacity of the species for adaptation to environmental changes, part of its AOO might be lost under severe climate change conditions. Key conservation areas were identified, and suggestions for redesigning some of the current natural reserves in the forested area where the species is found were proposed for the conservation of this key coniferous species. The stable area in the northwestern part of Yunnan in the Hengduan Mountain Forest can serve as a promising area for C. funebris reintroduction through afforestation programs.

Tapiscia sinensis Oliv. (T. sinensis), known as the Yingjiao tree, belongs to the Staphyleaceae family. It is a deciduous tree species endemic to China and represents an ancient species from the Tertiary glacial relics, possessing significant ecological and economic value. This study is based on 154 effective distribution points of T. sinensis in China and 12 environmental factors. Using integrated modeling and ArcGIS software (v10.8), the potential geographic distribution of T. sinensis under climate change was predicted to assess its future impact on distribution and ecological niche. Additionally, on-site surveys were conducted to compare the characteristics of T. sinensis forest communities across different habitability zones. The study also proposes conservation strategies based on the influence of climate change on the distribution of T. sinensis and the characteristics of its forest communities. The results indicate that (1) the current highly suitable areas for T. sinensis are primarily located in the municipal regions where Chongqing, Hubei, Hunan, and Guizhou provinces meet, covering an area of 20.44 × 10⁴ km². (2) In three suitable community categories, T. sinensis is consistently a subdominant species, with the community in moderately suitable areas being the most diverse and exhibiting higher stability and evenness. (3) Under future climate change scenarios, the potential distribution area for T. sinensis will gradually decrease with rising temperatures. It will shift toward northern higher latitude regions, with the degree of ecological niche migration also increasing. (4) Conservation measures for T. sinensis primarily involve in situ and ex situ protection approaches. These results provide a theoretical basis for the scientific management and resource conservation of T. sinensis.