Abstract:
The carbon sequestration services provided by ecosystems are one of the most important means toachieve carbon neutrality. Clarifying the driving mechanisms of environmental factors is an important basis for effectively improving carbon sequestration services of eocystems. This study takes the Wujiang River Basin as a study area, uses the InVEST model to valuate carbon storage in the Wujiang River Basin from 2000 to 2020, integrates the influencing factors in the social-economic-natural system, and uses the random forest and PDP models to analyse the contribution of each factor to the carbon sequestration services and the driving mechanisms. The results show that: ① the spatial distribution of carbon sequestration services in the Wujiang River Basin is characterized by high value in the northeast and low in the southwest, showing a trend of downstream > midstream > upstream and a significant increase over time, and the growth rate at the upstream is greater than that at the midstream and downstream; ② in the spatial and temporal dimensions, natural surface factors are the environmental factors that contribute most to the carbon sequestration service, among which vegetation cover has the highest contribution, which is 55.08% in the spatial scale and slope has the highest contribution, with 34.46% in the temporal scale; ③ the influencing factors show different driving mechanisms in space and time, with the strongest change in the driving mechanism of population density, in space, the carbon sequestration service decreases with population increase, and over time, the carbon sequestration service increases with population increase overall; and ④ from 2000 to 2020, the change of human activities is an important reason for the increase of carbon sequestration services of ecosystems in the Wujiang River Basin, and climate change is also an important influencing factor. The results show that although the level of carbon sequestration services is limited by natural surface environmental factors, the positive disturbance of human activities can significantly increase carbon sequestration services of the basin ecosystems.