Dispersal Corridors For Plant Species In Poyang Lake Basin Identified By Integration Of Genetic And Geospatial Data

The Poyang Lake Basin is one of natural geographic units with plenty of heat and precipitation in the subtropical China,providing suitable habitats for a high number of organisms.However,the biodiversity in this region has been threatened by anthropogenic induced global warming and habitat fragmentation,calling for the needs of constructing dispersal corridors to mitigate their adverse effects.Nevertheless,measuring the dispersal of wildlife through landscapes is notoriously difficult.Recently,the least cost path(LCP)calculation coupled with population genetic data and species distribution models has been applied to reveal the population connectivity.In this study,we used this method to identify the possible dispersal corridors of five plant species(Castanopsis tibetana,Schima superba,Cyclocarya paliurus,Sargentodoxa cuneata,Eomecon chionantha)in the Poyang Lake Basin(PLB,largely coinciding with Jiangxi Province),China,in the late Quaternary.Population samples of C.tibetana(39 populations/262 individuals),S.superba(44/364),C.paliurus(26/194),S.cuneata(58/417),E.chionantha(20/127)were collected across their distribution ranges in Jiangxi.Every two chloroplast for each specie were sequenced to assess population genetic data and species distribution models.The results showed that the strongest population connectivity for the five species occurred in the Wuyi Mountains and the Yu Mountains of the eastern PLB(East Corridor)during the late Quaternary.In the western PLB,populations of the five species were connected by the Luoxiao Mountains and the Jiuling Mountains but with a lower degree of possibility as a corridor(West Corridor).There were some connections between the eastern and the western populations across the Gannan Hills.When the corridors of five species were overlapped,the East Corridor and the West Corridor were mostly shared by multiple species.These results indicate that plant species in the PLB could have responded to the Pleistocene climate changes by moving along the East Corridor and the West Corridor.Given the dispersal corridors have seldom been considered in the governmental strategies of biodiversity conservation in the PLB,preserving and restoring natural vegetation along these corridors should be prioritized to mitigate the effects of human caused climate change and habitat fragmentation by allowing migration of plant species as well as the biota as a whole.