中国特有属秤锤树属植物的潜在分布区预测

秤锤树属（Sinojackia）是中国特有属，包括7个物种，各物种的种群及个体数量均较少，预测其潜在适宜分布区及其主要影响因素对制定保护措施至关重要。该研究在全面收集秤锤树属植物分布位点数据的基础上，结合气候、土壤和植被数据，运用物种分布模型（MaxEnt）和ArcGIS，预测该属植物当前的分布范围以及未来（2050s和2070s）潜在分布区的变化，分析影响该属植物分布的主要环境变量。预测结果显示：（1）当前秤锤树属高适宜地区主要在我国的亚热带地区，分布在长江中下游平原，包括湖南、浙江的大部分地区，河南、安徽和江苏南部地区以及湖北和江西两省交界处，四川、贵州零星分布着高适宜度位点；纬度范围为25.42°~31.84°N。（2）当前秤锤树属的高适宜性（0.665）生境面积仅为4.07×10⁴ km²，占国土面积的4.23％，分布区极为狭窄。未来（2050s和2070s）的高适宜分布地区将大幅度缩减，其中在2070s的RCP8.5排放情景下减少最多。（3）随着温度的上升，秤锤树属植物有向高纬度迁移的趋势。研究结果可为濒危植物的就地保护提供科学依据，同时也可为其迁地保护位点的选择提供参考。

Modeling potential distribution of an endangered genus (Sinojackia) endemic to China

Sinojackia, a genus endemic to China, includes seven species with a small number of populations. To develop effective conservation measures, it is important to understand the potential distribution of endangered endemic plant species and the underlying environmental factors. Here, we collected extensive occurrence data of Sinojackia, and then extracted climate, soil, and vegetation data from several datasets. We utilized the species distribution model (MaxEnt) and ArcGIS to predict the current and future potential distributions (2050s and 2070s) of the genus, as well as changes in potential distribution areas in the future. We also analyzed the major environmental variables that affected the distribution of the genus. Results show that: (1) The current high suitability distribution areas are mainly located within the subtropical regions of China. Specifically, the Middle-Lower Yangtze River Plain, including most parts of Hunan, Zhejiang, the southern areas of Henan, Anhui, and Jiangsu, the areas around the Hubei and Jiangxi boundary, and some sporadic regions in Sichuan and Guizhou. The latitude spans 25.42° to 31.84°N. (2) In addition, the current high suitability distribution area (0.665) is extremely narrow, totaling 4.07×10⁴ km², accounting for 4.23% of the total area of China. Furthermore, suitable distribution will decline in the future (2050s and 2070s). Of note, the area under a RCP8.5 emissions scenario in the 2070s will be substantially reduced. (3) With the increase in temperature in the future, the genus will migrate to higher altitudes. Our results are critical for the establishment of nature reserves for in-situ conservation and for the selection of sites for ex-situ conservation.