Mammal Diversity In Southwest China And The Impact Of Climate Change On The Diversity Of National Key Protected Species

The geographical pattern of biodiversity and the impact of climate change on biodiversity is one of the central issues in macroecology and biogeography,and it is also an important reference and basis for global and regional species diversity protection.Ecologists and biogeographers have put forward many hypotheses to explain the origin of species richness pattern,and have carried out a lot of tests.However,there are still widespread disputes about the status of different hypotheses and the dominant factors of large-scale geographical pattern of species richness.China has a vast territory,complex terrain,diverse climate and rich species.It is one of the 12 "countries with great diversity" in the world.Southwest China is the most abundant area of species diversity,which is suitable for the study of species richness pattern.However,due to the lack of accurate species distribution data,the previous studies on the geographical pattern and climate change of terrestrial mammal richness in Southwest China have been limited The effect of urbanization on species diversity is rare.Based on comprehensive and detailed species distribution data,combined with climate,terrain,vegetation and other environmental information,this study explored the pattern of terrestrial mammal richness in Southwest China and the impact of climate change on the distribution of species diversity of national key species in Southwest China(1)Through the literature,zoology and other information,we collected the species distribution directory of Southwest China,which belongs to 12 orders,40 families,177 genera,a total of 382 species,including 360 species with latitude and longitude information,and 7958 data of wild mammal species with latitude and longitude points were recorded.(2)Through the calculation formula of G-F index,the G-F index of Southwest China is 0.78 for Guizhou,0.83 for Sichuan,0.77 for Tibet,0.85 for Yunnan and 0.73 for Chongqing.G-F index can objectively and comprehensively reflect the species diversity of a region for a long time.The results of G-F index analysis can reflect the typical characteristics of biodiversity hotspots in Southwest China.(3)Based on the integrated model,the hot spots of mammal diversity pattern in Southwest China are predicted,including most areas of Yunnan,including Xishuangbanna in the south,Ailao Mountain and Wuliang Mountain in the middle,Hengduan Mountain from the west to the north,and the line from Minshan Mountain to Qionglai mountain in Sichuan Basin.The area from the border of China and Vietnam to Xishuangbanna and the southern section of Hengduan Mountains in southern Yunnan are the most species rich areas.The hot spots of species richness are all concentrated in this area,and the surrounding areas of these hot spots also have high species richness,including most of the mountainous and hilly areas in Guizhou and Minshan area in Sichuan.The species richness values of the above areas are all over 100 species.However,the species richness of the Qinghai Tibet Plateau is relatively low,and the hinterland of the Qinghai Tibet Plateau is the region with the poorest mammalian richness,with less than 30 species.(4)Based on the future climate data,the distribution of species diversity was predicted by the integrated model.The national key mammal species in Southwest China are basically distributed in the whole southwest region.Compared with the simulation results based on the current climate data,in the future climate model,except for this model in the rcp4.5 scenario 2050s,the highest species richness values of the other three models are relatively reduced.In the rcp8.5 scenario 2050s,the highest values of the national key mammals are reduced most,only 45 species,a decrease of 10%.Under these three models,the highest species richness was 46 species in the 2070s of rcp4.5 and rcp8.5 scenarios,with an area of 146.72 km2 and 62.88 km2,respectively.Compared with the predicted area of 4212.96 km2 of 46 species in the baseline climate,the area decreased by 96.52%and 98.51%.By the 2070s,climate change reduced the species richness of 46-50 species of national key mammals in the study area by 100%.From the prediction map of species richness distribution pattern obtained by integrated model simulation,it can be seen that the climate niche suitable for national key mammals in Southwest China will gradually decrease in the future,mainly in 2070s under rrcp4.5 model and 2050s and 2070s under rcp8.5 model.Under these three climate models,species richness will decrease.