Comparative Study On The Relationship Between The Northern Grassland And The Southern Hilly Regions Of China And Climate Change

The research on the relationship between biodiversity reduction and global climate change has been a hot topic in the world.In the face of the ecological and environmental problems caused by climate change,such as the decrease of plant diversity and the degradation of ecosystem services,how to effectively deal with and adapt to climate change has become an urgent issue to explore.Based on remote sensing images,ecosystem service value and climate data,we analyzed the spatiotemporal trends of plant beta diversity in the northern grassland and the southern hilly region,and discussed the similarities and differences of the main climatic factors driving the changes of plant beta diversity and ecosystem service value.In terms of temporal variation,the inter-annual plant beta diversity in the northern grassland showed a significant decline,and inter-annual changes of plant beta diversity in the southern hilly regions showed that the plant diversity in Chongyi and Lechang increased,while that in Cili,Danjiangkou and Huaying decreased.In terms of spatial variation,the stability of beta diversity spatial distribution in southern hilly region was higher than that in northern grassland.The west of Anxi,the northwest of west Ordos,the west of Xilingol,and the north,middle and south of Tumuji had high coefficient of variation and poor stability of plant beta diversity in the northern grassland.In the southern hilly region,the southern and eastern marginal regions of Chongyi,the northern and central regions of Cili,the southeast of Danjiangkou,the west and east of Lechang,and the southwest of Huaying,the coefficient of variation of plant beta diversity is large,with the most obvious inter-annual fluctuation of diversity and poor stability.The regression equation between plant beta diversity and climate factors showed that inter-annual plant beta diversity was very sensitive to temperature changes in the northern grassland region and the southern hilly region.In particular,monthly temperature variables had more significant effects on plant diversity.Temperature increase will decrease plant diversity,and there is a critical value for the effect of temperature on plant diversity in some regions.In the northern grassland region,plant diversity in Anxi and West Ordos was mainly affected by climatic factors related to monthly mean temperature.Plant diversity in Tumuji was affected by low monthly temperature,and too low temperature would reduce plant diversity.Xilingol is mainly affected by precipitation factors in summer season.Generally speaking,the increase of precipitation in summer contributes to the increase of plant diversity.In the southern hilly region,monthly high temperature is an important factor affecting plant diversity.No meteorological factors have been introduced into the Huaying,indicating that the change of temperature and precipitation is not the key driving force for the change of plant diversity in the mountainous area of the Huaying.The regression equation of ecosystem service value and climate factors showed that there were significant differences in the main climate driving forces of ecosystem service value in the north and south of China,and the main climate driving forces of different types of ecosystem service value in the same study area were also different.In the northern grassland region,soil conservation and hydrological regulation in Anxi are always affected by climatic factors.Except for soil conservation,all service types in the study area of west Ordos were affected by climate factors.The water supply and hydrological regulation in Xilingol study area are always affected by the monthly mean precipitation factor,while the temperature related variables have a stable influence on gas regulation,environmental purification and soil conservation.In Tumuji,climate factors only have a great impact on water supply and hydrological regulation.In the southern hilly regions,the ecosystem service value of the Huaying is significantly affected by monthly high temperature factors.However,climate factors could not explain the change mechanism of service value in Chongyi,Cili,Danjiangkou and Lechang regions.Monthly temperature and precipitation data can be used to accurately understand the specific driving forces of plant diversity change.While predicting future changes in plant diversity,effective measures should be taken to respond to the decreasing trend of plant diversity.The dynamic changes of plant diversity in different ecosystem types can be monitored timely and effectively,which can provide scientific basis for the implementation of ecological engineering.