基于MaxEnt模型的濒危植物丹霞梧桐潜在适生区预测

Assessment of potential distribution for endangered plant Firmiana danxiaensis based on MaxEnt modeling

模拟预测濒危植物丹霞梧桐(Firmiana danxiaensis)的潜在适生区,对合理指导保护该植物有重要意义。通过MaxEnt(最大熵模型)和ArcGIS,基于广东南雄丹霞梧桐自然保护区野外实地调查的16个分布点,及生物气候、地形和地貌覆被多重环境变量,对丹霞梧桐在广东南雄丹霞梧桐自然保护区的潜在适生区进行模拟预测。结果显示,模拟训练集和测试集的AUC值分别为0.851和0.913,预测结果准确性高。丹霞梧桐的高、中适生区主要分布在南雄丹霞梧桐自然保护区南部,占总面积40.45%;影响丹霞梧桐分布的主要环境因子包括地貌成因、土地覆被、最旱季降水量、坡度及等温性等,其中地貌成因(贡献率75.8%)是影响丹霞梧桐潜在分布的最主导因子。综合分析表明,丹霞梧桐的潜在适生区为海拔150—300 m、坡度30°—55°、年度气温范围28.3—28.6℃,最旱季降水量135—137 mm之间的侵蚀分化低丘陵丹霞地貌,适生的气候条件为温度相对较高、降水量少的区域。上述研究结果可为丹霞梧桐的保护与恢复提供理论依据。

Predicting the potential habitats of the endangered plant Firmiana danxiaensis has significance for scientific management of the species.Based on the field investigation 16 distribution points of F.danxiaensis,combined with bioclimate,topography and geomorphologic cover factors,the distribution of potential suitable habitats the of F.danxiaensis was simulated and predicted in F.danxiaensis Nature Reserve in Guangdong Province by MaxEnt model and ArcGIS.The results showed that the AUC values of the training set and test set were respectively 0.851 and 0.913,indicating that the predicting results were reliability.The high and moderate potential distribution areas of the F.danxiaensis were mainly located in the south of the reserve,accounting for 40.45%of the total area.The main environmental factors affecting the distribution of F.danxiaensis were geomorphic causes,land cover,precipitation of the driest quarter,slope and isothermality,among which the geomorphic cause(contributing 75.8%)was the most important factor.Further analysis demonstrated that the optimum distribution areas for F.danxiaensis were an elevation of 150-300 m,a slope of 30°-55°,air temperature annual range from 28.3℃to 28.6℃,recipitation of the driest quarter from 135mm to 137 mm and Danxia landform with erosion differentiation and its suitable climatic conditions were relatively high temperature and less precipitation.The results provided a theoretical basis for the protection and restoration of F.danxiaensis.