基于MaxEnt模型预测中华秋沙鸭在中国东北地区的潜在分布区

Predicting the Potential Distribution Area of the Scaly-sided Merganser in Northeast China Based on the MaxEnt Model

了解物种适宜生境的空间分布格局并准确地评估物种栖息地的适宜性对物种保护具有重要意义。通过野外调查、文献检索以及全球生物多样性信息平台(GBIF)获取东北地区中华秋沙鸭(Mergus squamatus)的87个分布点,利用ENMTools最终筛选79个有效分布点和10个重要环境变量,使用优化后的最大熵模型(MaxEnt)对中华秋沙鸭的潜在分布区进行预测。结果表明:东北地区中华秋沙鸭高适宜区主要位于长白山山脉和小兴安岭东部地区,较适宜区主要位于松嫩平原与辽河平原东部、长白山山脉西部地区,低适宜区主要位于三江平原、辽河平原与辽东丘陵地区。影响模型预测的主导环境特征变量是年降水量(61.2%)、降水量变异系数(14.9%)和等温性(10.8%)。此外,在地形因子中,距水源距离(5.9%)和海拔(1.7%)对中华秋沙鸭适宜生境选择同样有重要影响。其中AUC为(0.908±0.041),表明该模型可预测我国东北地区中华秋沙鸭的潜在分布区,可为制定中华秋沙鸭的保护政策提供理论依据。

It is important for species conservation to understand the spatial distribution pattern of suitable habitats and ac⁃curately evaluate the suitability of species habitats.We obtained 87 distribution sites of the scaly-sided merganser(Mergus squamatus)in northeast China through field surveys,literature searches,and the Global Biodiversity Information Facility(GBIF)data,and used the ENMTools to screen 79 effective distribution sites,and 10 important environmental variables.The optimized maximum entropy model(MaxEnt)was used to predict the potential distribution areas of scaly-sided mergan⁃ser.The results showed that:the highly suitable areas for the scaly-sided merganser in northeast China were mainly lo⁃cated in the eastern part of the Changbaishan Mountain and the eastern part of the Xiaoxinganling Mountain,and the more suitable areas were located in the eastern part of the Songnen Plain and Liaohe Plain and the western part of the Chang⁃baishan Mountain,low-suitable areas were mainly located in the Sanjiang Plain,Liaohe Plain and Liaodong Hills.The domi⁃nant environmental characteristic variables affecting the model prediction were annual precipitation(61.2%),precipitation coefficient of variation(14.9%),and isothermality(10.8%).In addition,among the topographic factors,the distance from water source(5.9%)and elevation(1.7%)also had the significant effects on the selection of suitable habitats for the scalysided merganser.The AUC value was(0.908±0.041),which indicated that the model could predict the potential distribu⁃tion area of the scaly-sided merganser in the northeast of China and provide a theoretical basis for the development of a con⁃servation policy for the scaly-sided merganser.