不同气候情景下独花报春属在中国的潜在分布格局变化预测

Prediction of Potential Distribution Pattern Changes of Omphalogramma Franch under Different Climate Scenarios in China

关键词:  独花报春属  最大熵（Maxent）模型  气候变化  潜在分布  适宜生境

Key words:  Omphalogramma Franch  Maximum-Entropy (Maxent) model  climatic change  potential distribution  suitable habitat

摘要:

气候变化是影响植物分布的主要因素。独花报春属植物在我国的分布区狭窄，生态位相似，多个物种处于濒危状态，预测不同气候情景下该属物种潜在地理分布范围的变化对保护物种多样性具有重要的意义。本文基于独花报春属（Omphalogramma）9个物种的106条分布记录以及14个高分辨率的环境变量，利用最大熵（Maxent）算法构建独花报春属物种在我国潜在适宜生境的预测模型，识别了关键环境变量，并借助GIS技术分析了独花报春属物种在冰期、当前和未来不同气候情景下的地理分布格局变化。结果表明：独花报春属潜在适生境预测模型的准确度非常高（AUC=0.97），当前的潜在适生区主要分布在云贵高原西部、川西高原至四川盆地、喜马拉雅山脉部分地区。温度年较差、等温性、最低月均辐射量和年降水量是影响独花报春属地理分布格局的主要环境变量。在末次盛冰期，独花报春属物种经历了种群的收缩并将喜马拉雅山脉东段和横断山作为避难所；在中世纪以后，种群向西南方向扩张。未来随着全球变暖，独花报春属的潜在适宜分布范围将进一步收缩，丧失的生境主要集中在云南南部热带气候区。建议在以后的保护工作中应该重点监测此区域的种群变化，采取合理的就地和迁地保护措施以有效保护独花报春属物种。

Abstract:

Climate change is the primary factor influencing plant distribution. The genus Omphalogramma has a narrow distribution range in China, with similar ecological niches, and several species are endangered. Predicting the potential geographic distribution range changes of species within this genus under different climate scenarios is of significant importance for biodiversity conservation. Using data from 106 records of nine Omphalogramma species and 14 environmental variables, we created a predictive model with Maxent to identify potential habitats in China. We simulated their distribution under different climate scenarios across the glacial period, present, and future, and analyzed the environmental factors affecting their spatial distribution using GIS technology. The results showed that the accuracy of the model was very high (AUC=0.97). Presently, potential habitats primarily exist in the western Yunnan-Guizhou Plateau, western Sichuan Plateau extending to the Sichuan Basin, and portions of the Himalayan Mountains. The temperature annual range, isothermality, minimum monthly average radiation, and annual precipitation were identified as the main environmental variables affecting the geographic distribution of Omphalogramma. During the glacial period, the species experienced a population decline, seeking refuge in the eastern Himalayas and the Hengduan Mountains. Post-Middle Ages, populations expanded southwestward. In the future, global warming is expected to reduce the potential suitable range of the genus, with habitat loss concentrated in the tropical climate region of southern Yunnan. It is recommended that future conservation efforts should focus on monitoring population changes in this region and implementing appropriate in-situ and ex-situ conservation measures to effectively protect species of the genus Omphalogramma.