气候变化下华南五针松在中国的适生区预测

Suitable habitat prediction of Pinus kwangtungensis in China under climate change

华南五针松(Pinus kwangtungensis)是一种较原始、较古老的单维管束植物,为国家二级重点保护野生植物,预测不同气候背景下华南五针松的分布变迁对其野生资源保护具有重要意义。基于现有的华南五针松分布点和气候数据,利用最大熵模型(MaxEnt)和ArcGIS软件预测当前和未来不同气候情景下的华南五针松适生区及未来变迁规律,并通过气候变量贡献值、置换重要性值及刀切法揭示影响华南五针松分布的主要气候因子。结果表明:模型模拟训练集和测试集的特征曲线下面积值(area under curve,AUC)均大于0.995,模拟结果可靠;最暖季度降水量是影响华南五针松分布的关键气候因子。当前时期,华南五针松适生区主要位于广东北部、广西以及贵州南部地区,占中国国土面积的17%。在未来不同气候背景下,华南五针松适生区的面积和分布发生显著改变,2041—2060年,其总适生区面积随着温室气体浓度的上升呈现先减少后增加的趋势;2061—2080年,其总适生区面积随温室气体浓度的上升而逐渐下降。基于以上研究结果,建议将广西除南部外的其他地区、广东西北部、贵州南部边缘等华南五针松的稳定适生区作为应对未来气候变化的重点保护区域,并对广西南部边缘、广东南部等区域进行优先保护。该研究结果可为华南五针松应对未来不同气候变化和迁地保护提供科学依据。

Pinus kwangtungensis is a relatively primitive and ancient single vascular plant,which belongs to national second-class key protected wild plant.Predicting the distribution changes of Pinus kwangtungensis under different climatic backgrounds is of great significance for the protection of its wild resources.Based on the existing distribution points of Pinus kwangtungensis and the climate data,this study used the maximum entropy model(MaxEnt)and ArcGIS software to predict the suitable habitats and future changes of Pinus kwangtungensis under different climate scenarios,and revealed the main climatic factors affecting the distribution of Pinus kwangtungensis through the contribution value of climatic variables,the importance value of replacement and the knife cut method.The results show that the AUC values of the model simulation training set and the test set are all higher than 0.995,and the simulation results are reliable.The precipitation in the warmest quarter is the key climatic factor affecting the distribution of Pinus kwangtungensis.At present,the suitable habitats of Pinus kwangtungensis are mainly located in northern Guangdong,Guangxi and southern Guizhou,accounting for 17%land area of China.Under different climatic backgrounds in the future,the area and distribution of the suitable habitats of Pinus kwangtungensis change significantly.From 2041 to 2060,the total area of suitable habitats decreases first and then increases with the increase of greenhouse gas concentrations.From 2061 to 2080,the total area of suitable habitats gradually decreases with the increase of greenhouse gas concentrations.The above results suggest that the stable suitable habitats of Pinus kwangtungensis in Guangxi(except the southern region),northwestern Guangdong and the southern edge of Guizhou should be taken as the key protection areas to cope with future climate change,and priority protection should be given to the southern edge of Guangxi and southern Guangdong.This study provides a scientific basis for coping with different climate changes and ex-situ protection of Pinus kwangtungensis in the future.