Abstract:
The Yangtze River Economic Belt is an important area of contributing carbon sink in China. Exploring the spatiotemporal evolution and driving mechanism of carbon sink is beneficial for promoting carbon reduction, increasing carbon sink, and regional low-carbon development. Thus, the paper analyses the spatiotemporal evolution characteristics and drivers of carbon sinks in the Yangtze River Economic Belt based on land use data, socio-economic data and other data from 2000 to 2020 by using standard deviation ellipses, center of gravity migration models and Geodetector. The results show that: (1)Temporally, both the total amount and intensity of carbon sinks in the Yangtze River Economic Belt are fluctuating and increasing from 2000 to 2020, but the intensity of carbon sinks in the middle and lower reaches fluctuates more frequently in time sequence, with woodland being the largest carbon sink, with an average annual carbon sequestration of about 6817.66×10
4 t. (2)Spatially, The intensity of carbon sinks at the provincial scale shows a distribution pattern of "high in the south and low in the north, high in the west and low in the east". The distribution of total carbon sinks and woodland carbon sinks has a strong spatial consistency, concentrating in the middle and upper reaches and showing a characteristic of expansion followed by contraction and migration to the west; the carbon sinks of waters are mainly in the middle and lower reaches, showing a westward expansion trend; the carbon sinks of grassland and unused land are mainly distributed in the western plateau of Sichuan province and have contracted in scope. (3) In terms of the migration of the center of gravity, woodland carbon sinks follow a similar trajectory to the total carbon sinks, moving 18.81 and 17.76 km to the northeast and then west respectively; grassland carbon sinks move 21.76 km to the north and unused land carbon sinks move 32.38 km to the west; in contrast, watershed carbon sinks move the longest, cumulatively leaping about 73.46 km to the west. (4) In terms of the influencing factors, the size of carbon sinks in the Yangtze River Economic Belt is influenced by a combination of both natural and socio-economic factors, with natural factors having the greatest influence, and national policies and land use intensity among the socio-economic factors also having a more significant influence; the influence of any two drivers when they interact is greater than that of a single factor. The study shows that the spatial and temporal evolution of carbon sinks and the influencing factors vary significantly among regions in the Yangtze River Economic Belt. Therefore, it is recommended that each region should seek differentiated low-carbon pathways and optimize the structure of land for carbon sinks, and formulate environmental policies and land use planning to promote regional carbon sink potential and low-carbon development.