Bioclimatic variables used in the study.

Climate change has emerged as a significant driver of biodiversity loss, with profound implications for species distribution. This study assessed the current and future distribution of Tecomella undulata (Desert teak), an economically and medicinally valuable species facing threats from climate change. MaxEnt model, built using 44 occurrence points and environmental data including bioclimatic factors and Digital Elevation Model (DEM), demonstrated an impressive Area Under the Curve (AUC) value of around 0.91 and a True Skill Statistic (TSS) value of 0.79, indicating excellent predictive performance. Temperature seasonality (Bio4) emerged as the most crucial variable, contributing 35.9% to the modeling, followed by the mean temperature of the wettest quarter (Bio8) and precipitation seasonality (Bio15). The habitat suitability maps showed a strong presence of T. undulata in the southern regions of Iran, with Fars and Bushehr provinces being particularly conducive to its growth. Future projections under Shared Socioeconomic Pathways (SSP) scenarios SSP245 and SSP585 for 2030, 2050, 2070, and 2090 suggested a decline in suitable habitats for T. undulata, with high-suitability areas projected to decrease by up to 98% and unsuitable habitats predicted to increase. The study underscores the urgency for tailored conservation measures to mitigate the impacts of climate change on this valuable species.

气候变化已成为生物多样性丧失的关键驱动因子，对物种分布格局产生深远影响。本研究针对兼具经济与药用价值、正受气候变化威胁的沙漠柚木（Tecomella undulata，Desert teak），评估了其当前及未来的分布状况。研究基于44个物种分布记录点与包含生物气候因子、数字高程模型（Digital Elevation Model，DEM）在内的环境数据构建MaxEnt模型，该模型的曲线下面积（Area Under the Curve，AUC）值约为0.91，真实技能统计量（True Skill Statistic，TSS）值达0.79，展现出优异的预测性能。其中温度季节性（Bio4）为最重要的环境变量，对模型贡献率达35.9%，其次为最湿季平均温度（Bio8）与降水季节性（Bio15）。生境适宜性图谱显示，伊朗南部为该物种的主要适生区域，法尔斯省（Fars）与布什尔省（Bushehr）尤其适宜其生长。基于共享社会经济路径（Shared Socioeconomic Pathways，SSP）下的SSP245与SSP585情景，对2030、2050、2070及2090年的未来预测结果表明，沙漠柚木的适生生境将持续缩减：高适宜生境预计最多减少98%，而不适生生境则呈扩张态势。本研究强调了制定针对性保护措施以缓解气候变化对该珍贵物种不利影响的紧迫性。