西北干旱区白刺属植物适生环境的模拟分析

白刺属(Nitraria L.)植物是古地中海第三纪孑遗植物,对我国西北干旱、半干旱地区具有极高的生态效益。本研究基于MaxEnt模型和ArcGIS软件及其SDM工具箱预测了过去到未来不同时期下白刺属6个物种在我国的潜在适生区及其迁移路线,以期为该属植物的保护及资源利用方面提供一定的理论依据。结果表明:白刺属植物当代在我国的高适生区面积占我国国土总面积的6.32%,主要集中在宁夏北部、内蒙古南部和新疆西部地区。与过去相比,白刺属植物的潜在高适生区在当代减少了1.68%。与当代相比,白刺属植物高适生区预测面积在2070年(RCP4.5)气候情景下减少了0.13%,在2070年(RCP8.5)气候情景下增加了1.61%,主要集中在甘肃东南部和宁夏地区;白刺属植物在我国潜在适生区的主导环境因子是最冷月最低温(bio6);最冷季度的平均降水量(bio19)和年均温(bio1)是影响白刺属潜在地理分布的主要环境因子;白刺属植物在末次间冰期(LIG)、末次冰盛期(LGM)、当代及2070年(RCP4.5和RCP8.5)均有向青海等高海拔地区迁移的趋势。

Simulation and analysis of the suitable environment for Nitraria L.in the arid area of Northwest China

Nitraria L.are the tertiary relic plants of the Paleo-Mediterranean,which have high ecological benefits for arid and semi-arid areas in northwest China.Based on MaxEnt model,ArcGIS software and SDM toolbox,the potential distribution areas and migration routes of six species of Nitraria L.in China in the past and future were predicted in this study,in order to provide a theoretical basis for the protection and resource utilization of Nitraria L.The results showed that the high potential area of Nitraria L.in China accounted for 6.32%of the total land area,mainly concentrated in northern Ningxia,southern Inner Mongolia and western Xinjiang.Compared with the past,the potential high suitable area of Nitraria L.decreased by 1.68%in the current period.Compared with the present,the predicted area of high adaptive area of Nitraria L.would decrease by 0.13%in 2070(RCP4.5)climate scenario,and increase by 1.61%in 2070(RCP8.5)climate scenario,mainly concentrate in southeastern Gansu and Ningxia.The dominant environmental factors influencing the potential suitable growing areas of Nitraria L.in China are the lowest temperature in the coldest month.The average precipitation and average annual temperature in the coldest season are the main environmental factors affecting the potential geographical distribution of Nitraria L..In the last interglacial stage(LIG),the last glacial maximum(LGM),the current period and in 2070(RCP4.5 and RCP8.5),Nitraria L.plants showed a tendency to migrate to Qinghai and other high elevation areas.