气候变暖背景下春兰和蕙兰的适生区分布预测

为了阐明气候变暖背景下春兰(Cymbidium goeringii)和蕙兰(C. faberi)在我国的适生区分布变化情况,根据157条分布记录和19个生物气候变量,应用最大熵物种分布模型,对2070年4种温室气体排放情景下春兰和蕙兰在我国的适生区分布进行预测,并筛选影响其地理分布的主要气候因子。结果表明:(1)2070年春兰和蕙兰分布点的年均温(bio1)、最冷月最低温度(bio6)和最冷季平均温度(bio11)等均升高,气候有变暖趋势;(2)受试者工作特征曲线下面积(AUC)值在0.9—1.0之间,模型预测结果可信度较高;(3)影响春兰、蕙兰当前和2070年地理分布的限制性气候因子主要有最冷月最低温度(bio6)、最冷季平均温度(bio11)、年均降水量(bio12)和最干月份降水量(bio14);(4)气候变暖将会对春兰和蕙兰的适宜生境范围和面积产生影响。预测2070年春兰的适宜生境面积将会有所减小,而蕙兰的适宜生境面积将会增加,且整体有向北迁移的趋势。研究结果为野生春兰和蕙兰的生态风险评价和引种提供了重要依据。

Prediction of the potential geographical distribution of Cymbidium goeringii and C. faberi under the background of global warming

To evaluate how climate change may influence species distribution, we simulated the potential geographical distribution of Cymbidium goeringii and C. faberi under current and 2070 climate conditions based on 157 species presence data sets and 19 bioclimatic variables using MaxEnt software. The climate change model showed increases in the annual mean temperature, minimum temperature of the coldest month, and mean temperature of the coldest quarter. The area under the receiver operating characteristic curve (AUC) values for these factors varied from 0.9 to 1.0, which indicated that the prediction had high reliability. Four bioclimatic factors, minimum temperature of the coldest month, mean temperature of the coldest quarter, annual precipitation, and precipitation of the driest month, were the main bioclimatic factors affecting the geographical distributions of C. goeringii and C. faberi. With global warming, the area of suitable habitat for C. goeringii will shrink, whereas the area for C. faberi will expand and is projected to migrate northward. Our results provide scientific references for ecological risk assessment and introduction of C. goeringii and C. faberi.