Abstract:

Taxus wallichiana var. chinensis, a wild plant under China’s first-class national protection, is also listed as Vulnerable (VU) by the IUCN, highlighting its conservation status. Research on its potential distribution under climate change remains limited, posing challenges to its protection and management efforts. This study leverages the Biomod2 package, which integrates multiple modeling approaches, and combines current and future climate scenarios with various environmental factors, such as climate and topography, to analyze changes in the potential suitable habitat of Taxus wallichiana var. chinensis in Hubei Province, China. The results demonstrate that by ensemble modeling using multiple approaches, a more accurate composite model was achieved for predicting the potential suitable habitat of Taxus wallichiana var. chinensis. Furthermore, precipitation in the coldest quarter (bio19) had the most substantial influence on the distribution of suitable habitats. The suitability of Taxus wallichiana var. chinensis initially increased with increasing precipitation, peaking when precipitation exceeded 61 mm, after which it exhibited a declining trend. Under current climatic conditions, the potential suitable habitat for Taxus wallichiana var. chinensis is predominantly concentrated in the Qinba Mountains of western Hubei and the Wuling Mountains of southwestern Hubei, covering an area of approximately 15067 km², which accounts for 8.1% of the total study area. Under future climate scenarios influenced by global warming, the area of potential suitable habitat for Taxus wallichiana var. chinensis is projected to increase significantly. Additionally, the overall degree of habitat fragmentation is expected to decrease, with suitable habitats expanding toward mid- to low-altitude mountainous regions characterized by favorable hydrothermal conditions and greater topographic variations. This study further underscores the impact of future climate change on the expansion of potentially suitable habitats and the migration of distribution centers for Taxus wallichiana var. chinensis, providing a scientific foundation for its conservation and management in the Hubei Province. The integration of diverse environmental variables and advanced modeling techniques in this study enhances our understanding of how climate change may alter the ecological niche of this vulnerable species. These findings highlight the critical role of precipitation patterns, particularly during the coldest season, in shaping the habitat suitability. This insight is vital for developing adaptive conservation strategies, as it suggests that changes in precipitation regimes could either bolster or constrain the survival of Taxus wallichiana var. chinensis in certain regions of China. Moreover, the predicted expansion of suitable habitats into new regions under warming scenarios indicates a potential shift in conservation priorities, necessitating proactive measures, such as habitat restoration and corridor establishment to facilitate species migration. By identifying key areas of current and future habitat suitability, this study provides actionable insights for policy makers and conservationists. This emphasizes the need for dynamic management approaches that account for shifting environmental conditions and the ecological requirements of Taxus wallichiana var. chinensis. As climate change continues to reshape ecosystems, such research provides an essential framework for safeguarding Taxus wallichiana var. chinensis, ensuring its persistence amid the evolving challenges in Hubei Province and other regions. This study not only contributes to the conservation of a single species but also serves as a model for studying other climate-sensitive plants facing similar threats in the future.

Key words: Taxus wallichiana var. chinensis, climate change, SDMs, Biomod2, potential suitable habitat distribution, habitat fragmentation

摘要：

红豆杉（Taxus wallichiana var. chinensis）是国家一级重点保护野生植物，也被IUCN列为易危级（VU）保护物种。目前关于气候变化下红豆杉的潜在适宜生境的研究较少，导致对其保护面临挑战。基于Biomod2程序包运用并集成多种模型方法，结合当前和未来气候情景，利用气候、地形等多种环境因子，分析了湖北省红豆杉潜在适宜生境的变化。研究表明，通过对多种模型进行组合，获得了精度更高的综合模型以预测红豆杉潜在适宜生境。另外发现，最冷季降水量（bio19）对适生区分布的影响最大，红豆杉适宜性随着降水量的增加呈现先上升，当降水量大于61 mm时下降的趋势。当前气候条件下，红豆杉潜在适宜生境主要分布在鄂西秦巴山区和鄂西南武陵山区，面积约15067 km²，占研究区总面积的8.1%。在未来气候情境下，由于气候变暖的影响潜在适宜生境面积预计将明显增加，总体破碎度化程度降低，并向水热条件较好地形起伏较大的中低山区扩展。研究进一步强调了未来气候变化对红豆杉潜在适宜生境扩展与分布中心迁移的影响，为湖北省红豆杉未来保护与管理提供了科学依据。

关键词: 红豆杉, 气候变化, 物种分布模型, Biomod2, 潜在适宜生境分布, 生境破碎化