Using Species Distribution Modeling To Study The Diversity Patterns For Woody Plants Of The Loess Plateau

Various vegetation types have been recorded in the Loess Plateau.Meanwhile,this region is a famous transitional zone of forest,grassland and desert.Due to the special geological conditions and intensive human activities,the vulnerable environment is facing serious conservation challenges.Previous studies on biodiversity mostly focus on species,ignoring the genetic information retained by the evolution history.Incorporating phylogenetic relationships between species into biodiversity research can more comprehensively protect biodiversity and preserve biological potential.From the perspective of evolutionary history,our study analyzed the diversity patterns for woody plants of the Loess Plateau.First of all,we modeled the potential distribution of woody species by combining specimen records and climate data.The phylogeny of species was introduced to calculated the spatial patterns of species richness,weighted endemism,phylogenetic diversity and phylogenetic endemism.Additionally,we identified environmental drivers of the observed spatial patterns.Secondly,we modeled the spatial patterns for woody plants in the future(2070s)of the Loess Plateau,and considered the changes of current woody plant diversity patterns.Thirdly,we classified the types of endemism center and analyzed the migration of these endemism center under the climate change scenarios.The results of this study showed that the spatial pattern of species richness,weighted endemism,phylogenetic diversity and phylogenetic endemism of woody plants on the Loess Plateau decreased from southeast to northwest,and highly related to the flora of Qinling Mountains and Zhongtiao mountains.The annual precipitation and the minimum temperature of coldest month have the strongest explanatory power for the above metrics.The spatial patterns of woody plants in the 2070 s of the Loess Plateau is similar with the current patterns.All metrics showeddeclining trend,which indicates that woody plants of the Loess Plateau will face more sever risks in the future.Endemism centers were found on the southern edge of the Loess Plateau,which include paleo-endemism and mixed-endemism,without neo-endemism.In 2070 s,paleo-endemism,mixed-endemism,and neo-endemism centers will be found.We concluded that most woody species of the Loess Plateau originated in tropical or subtropical regions,and the species richness patterns of this region are maintained by dispersal rather than speciation.Our study is helpful to understand the mechanism of biodiversity formation of the Loess Plateau,and provide scientific basis and theoretical support for future biodiversity conservation and ecological restoration projects.