基于MaxEnt模型的广东省红豆属植物潜在适生区研究

Study on the Potential Suitable Area of Ormosia in Guangdong Province Based on the MaxEnt Model

为了解气候变化情景下广东省红豆属(Ormosia)潜在适生区的变化,探究影响红豆属植物潜在适生区的主导环境因子,本研究基于MaxEnt模型和ArcGIS 10.8软件,利用17种红豆属植物的分布数据及22个环境变量数据,结合未来共享社会经济路径(SSP126、SSP585)的气候情景,分别预测红豆属植物在当前和未来气候场景下的潜在适生区分布情况。结果表明:(1)适生区预测模型的评价效果良好,受试者工作特征曲线(Receiver Operating Characteristic curve,ROC曲线)下面积(AUC平均值)均为0.8-1.0。(2)在当前气候情景下,大面积(占广东省面积的40%-100%)适生的红豆属植物有茸荚红豆(Ormosia pachycarpa)等3种;中等面积(占20%-40%)适生的有薄毛茸荚红豆(O.pachycarpa var.tenuis)等6种;小面积(占5%-20%)适生的有韧荚红豆(O.indurata)等4种;极小面积(占0%-5%)适生的有凹叶红豆(O.emarginata)等4种。其中面积占比最大的是茸荚红豆,总适生面积为15.2288×10^(4) km^(2)(占84.75%);面积占比最小的是博罗红豆(O.boluoensis),总适生面积为0.0337×10^(4) km^(2)(占0.19%)。(3)降水和海拔对红豆属植物的分布起主导作用:12种红豆属植物适生区的主导环境因子为气候因子(9个降水因子,3个温度因子),剩余5种的主导环境因子是高程海拔因子(5个海拔因子)。(4)在未来(SSP126、SSP585)的气候情景下,潜在适生区面积增加的红豆属植物有凹叶红豆等4种,增加幅度为0.79%-42.43%;面积减小的红豆属植物有博罗红豆等13种,减少幅度为1.30%-78.56%。气候变暖对红豆属的潜在分布区具有一定的消极影响,17种红豆属植物中有13种的适生区面积将减少,特别是几个狭域分布的物种:博罗红豆、锈枝红豆(O.ferruginea)、小叶红豆(O.microphylla)、紫花红豆(O.purpureiflora)和亮毛红豆(O.sericeolucida),它们应是红豆属就地保护和迁地保护优先考虑的类群。

In order to understand the changes in the potential suitable areas of Ormosia in Guangdong Province under climate change scenarios and explore the dominant environmental factors affecting the potential suitable areas of Ormosia,based on the MaxEnt model and ArcGIS 10.8 software,this study used the distribution data of 17 species of Ormosia plants and the data of 22 environmental variables,combined with the climate scenarios of social and economic paths(SSP126,SSP585)to predict the distribution of potential suitable areas of Ormosia plants in the current and future climate scenarios.The results showed that:(1)The evaluation effect of the prediction model of the suitable area was good,and the Area under the Receiver Operating Characteristic curve(ROC curve)(average AUC values)were all in the range of 0.8-1.0.(2)Under the current climate scenario,Ormosia pachycarpa and other 3 species were suitable for growing in large area(accounting for 40%-100%of the area of Guangdong Province).6 species,including O.pachycarpa var.tenuis,were suitable for medium area(20%-40%).4 species,including O.indurata,were suitable for small area(5%-20%).4 species,such as O.emarginata,were suitable for very small area(0%-5%).Among them,the highest percentage of suitable area is O.pachycarpa,with a total area of 1522288 km 2,accounting for 84.75%;the smallest suitable area is O.boluoensis,with a total area of 337 km 2,accounting for 0.19%.(3)Rainfall and altitude play a leading role in the distribution of Ormosia plants.The dominant factors of the suitable area of 12 species of Ormosia plants were climatic factors(9 rainfall factors,3 temperature factors),and the dominant factors of the remaining 5 species were altitude factors(5 altitude factors).(4)Under the future climate scenarios(SSP126,SSP585),the potential suitable area of 4 Ormosia species would increase,including O.emarginata etc.,with an increase of 0.79%-42.43%.The potential suitable area of 13 Ormosia species would decrease,including O.boluoensis etc.,with a decrease of 1.30%-78.56%.Climate warming has a certain negative impact on the potential distribution area of Ormosia species.Among the 17 species of Ormosia,the suitable area of 13 species will be reduced,especially for several narrowly distributed species(O.boluoensis,O.ferruginea,O.microphylla,O.purpureiflora,and O.sericeolucida).They should be the priority groups of in situ conservation and ex situ conservation of Ormosia species.