Abstract:

Analyzing the spatial patterns of land use and carbon stocks in the Three Gorges reservoir area (Chongqing section) over the past decade, and simulating land change trends and predicting carbon stock variations under different scenarios for the next decade, can significantly aid in optimizing regional land use patterns and formulating effective ecological policies. We employed the InVEST model and examined 13 driving factors to analyze land use changes in the Three Gorges reservoir area (Chongqing section) from 2010 to 2020 and to predict trends for 2030 under various development scenarios. We also assessed carbon stock status using the PLUS model. Results reveal that: (1) From 2010 to 2020, land use changes in the Three Gorges reservoir area (Chongqing section) were primarily characterized by the conversion of arable land, grassland, and wetlands to forest land, construction land, and water bodies. Carbon stocks in 2010 and 2020 were 426.89×10⁶and 425.51×10⁶ t, respectively, indicating a decline of 1.38×10⁶ t. (2) Carbon stock distribution exhibited spatial differentiation, with lower levels in the west and higher levels in the east, lower in the south and higher in the north, and higher at the reservoir’s head compared to its tail. The spatial changes in carbon stocks closely aligned with changes in land types. Socio-economic factors, particularly population and GDP, contributed most significantly to the spatial pattern evolution. (3) By 2030, carbon stocks are projected to decrease by 0.76×10⁶ and 8.98×10⁶ t under natural scenario and urban development scenario, respectively, but increase by 3.72×10⁶ t under ecological protection scenario. The primary cause of carbon stock reduction is the transition from high-carbon-density land types to low-carbon-density land types. To address these issues, future strategies should focus on creating a balanced, coordinated, and low-carbon spatial land-use pattern, planning urban growth boundaries, and prioritizing the protection of high carbon-storage areas such as the Wushan Mountain System, Daba Mountain System, and Wuling Mountain System. Additionally, restoring forests and grasslands in reservoir tail areas is crucial to preserving carbon sink functions.

Key words: carbon stock, Three Gorges reservoir area, PLUS model, InVEST model, land use change