关键词: 气候变化, 攀枝花苏铁, 物种分布模型, 地理分布, 空间格局

Abstract: Climate exerts a significant impact on the geographical distribution of species. Investigating the potential distribution of Cycas panzhihuaensis under the context of climate change is beneficial for conservation. Based on the current distribution points of C. panzhihuaensis, we used the Maximum Entropy (MaxEnt) model to examine the influence of environmental variables on its geographical distribution. The spatiotemporal changes and centroid shift trends in the potential distributions of C. panzhihuaensis were predicted under various climate scenarios (SSP245, SSP585) for both the current and future periods (2050s, 2070s, 2090s). The results showed that: (1) The MaxEnt model performed well in predicting the distributions of C. panzhihuaensis (with an AUC of 0.980), indicating its suitability for further predictive applications. (2) The temperature seasonality, precipitation in the driest quarter, maximum temperature of the warmest month, and organic carbon stock were the main factors influencing the distribution of C. panzhihuaensis. (3) The total suitable habitat for the current distribution of C. panzhihuaensis was 316.58×10⁴ hm², with a highly suitable habitat of 33.87×10⁴ hm². Its distribution appeared relatively continuous, forming a branch-like pattern along the dry, hot river valley regions of the Jinsha River’s great bend and its tributaries. (4) Under future climate change scenarios, the suitable habitat for C. panzhihuaensis will expand. Under the SSP245 and SSP585 scenarios, the maximum total suitable habitat will reach 481.98×10⁴ and 589.16×10⁴ hm², respectively, representing increases of 52.25% and 86.10%. The centroid of the suitable habitat will shift northward by 124.53 and 111.80 km, respectively. The minimum values of highly suitable habitat reduced by 45.87% and 88.34%, respectively. The results indicate that while the overall suitable habitat increases, a significant decrease in the highly suitable habitat can pose serious challenges to the viability of C. panzhihuaensis. Our results can provide a scientific basis for the in situ conservation of C. panzhihuaensis, and provide a reference for the selection of sites for ex situ conservation, introduction, and cultivation.

Key words: climate change, Cycas panzhihuaensis, species distribution modelling, geographical distribution, spatial pattern