Study On Priority Conservation And Gap Analysis Of Vascular Plants In Southwest Region Of China

The southwest region harbored the most abundant biodiversity in China and it was also assessed as the biodiversity hotspot in the world.According to various kinds of literature as well as specimen records,we analyzed the spatial geographical distribution pattern of species richness at the macroscale.Then the spatial correlation area analysis was used to identify hotspots and further determine the priority conservation area for vascular plants in the southwest region of China.At last,we evaluated the current situation of protective network,identified the conservation gaps through GAP analysis and finally put forward scientific suggestions.Main results are as follows:(1)There are 24070 vascular plants(including subspecies and varieties)in southwest region,belonging to 310 families and 2547 genera,in which 22135 species are Angiospermae,154 species are Gymnospermae and 1781 species are Pteridophyte.Among them,11678 species were defined as endemic to China,accounting for 48.52%of all species.191 species were listed in protected category ? and 1208 species in category ?.(2)According to China's Red List of Biodiversity-higher plants,we obtained the level of threatened species:9(0.04%)species were asssessed as Extinct,4(0.02%)were assessed as Extinct in Wild,6(0.02%)were Reginal Extinct.There were 298(1.24%),768(3.19%),1196(4.97%)species assessed as Critically Endangered,Endangered and Vulnerable respectively.The above three types were defined as threatened status,accounting for 9.40%in total.Moreover,1678 species were assessed as Near Threatened,15662 species were Lease Concern and 1818 species were Data Deficient.(3)At provincial scale,Yunnan province harbored the most species,accounting for 68.65%of all species,followed by Sichuan(12805,53.19%),Tibet(8280,34.40%),Guizhou(7499,31.15%),Chongqing(6363,26.43%)successively.At county scale,vascular plants mainly distributed in the eastern section of the Himalaya Mountains,the partial area of the Hengduan Mountains,the district of Xishuangbanna and the southeast area of Yunnan.Top-ranked 25 counties with the most plants represented 18041 species,accounting for 74.95%of vascular plants in this region.(4)Using the G~i(?)coefficient we determined the priority conservationareas which primarily distributed in the east of Himalayan Mountains,thepartial area of Hengduan mountains,the northwestern regions of SichuanBasin,Daba Mountains,the junction of Himalayan Mountains and La-trackKangri Hill,Ailao Mountains area,the district of Xishuangbanna,thesoutheastern area of Yunnan.These regions cover an area of 26.96 million hm~2,representing 20153 species in the whole study area.(5)The southwest region has established various protected areas up to2014,among which 210 were nature reserves(76 were national naturereserves and the others were provincial nature reserves),covering an area of50.36 million hm2.Other types including 116 national forest parks,62national wetland parks,52 scenic spots and 44 national geoparks were 274 intotal.We superposed the distribution map of priority areas and existing naturereserves network to identified the conservation gaps.The results indicatedthat the gaps mainly appeared in the northwest and southwest of Sichuanprovince,the northwest and southeast of Yunnan province,and the district ofDaba mountains.Among them,the conservation gaps in the south of Tibetwere intensively large and other regions were scattered and small.Consequently,more attention should be paid for these areas in the futureplanning.The study is of great significance for plant biodiversity in southwestregions.Meanwhile,it also can provide scientific basis and policy.