[Spatio-temporal Evolution and Multi-scenario Simulation of Carbon Storage in Karst Regions of Central Guizhou Province：Taking Puding County as An Example].

Abstract

Regional land use change is the main cause for the change in karst carbon storage. It is important to analyze the spatial and temporal evolution and future spatial distribution trends of carbon storage in typical counties in central Guizhou's karst region， such as Puding County， to improve regional carbon storage， optimize land ecological security patterns， and promote low-carbon sustainable urban development. The PLUS-InVEST model was coupled， based on the interpreted land use data and future land prediction， the spatial and temporal evolution characteristics of land use change and carbon storage in Puding County from 1973 to 2020 were inverted， and the spatial pattern evolution of land use and carbon storage change under different scenarios in 2060 were simulated and predicted. The results showed： ① from 1973 to 2020， the overall carbon storage in Puding County increased by 6.61×105 t， showing an upward trend. The spatial distribution showed a significant increase in the northeastern and southwestern parts of Puding County and a significant decrease in the south-central parts. The change was due to the increase in carbon storage in dryland to shrubland and forest land and the decrease in carbon storage in areas where paddy fields are converted to construction land. ② The land use change in Puding County in the historical period was mainly reflected in the continuous expansion of construction land and the increased fluctuation of the proportion of forest land and shrub forest land， and the change in land use in different scenarios projected in 2060 retained the change characteristics of the historical period. ③ In 2060， the carbon storage in Puding County under the scenarios of natural evolution， ecological protection， and economic development increased by 2.93×105， 5.40×105， and 1.11×105 t， respectively， compared with that in 2020. Of these， the increase in ecological protection scenarios was the most significant， with the transfer of dryland to shrubland being the main reason for the increase in regional carbon sequestration capacity. These results can serve as a scientific reference for land use management decisions and the formulation of emission reduction and sink increase policies in Puding County. The future land use planning of karst areas should be guided by the goal of "carbon neutrality" in 2060， take appropriate ecological protection measures， strictly control the rapid expansion of construction land to paddy fields， optimize the land use structure， and effectively improve the level of regional carbon storage.