Spatiotemporal Evolution of Land-Use Carbon Emissions and Carbon Storage in Mountainous Towns of the Central Xuefeng Mountains, China

Under China’s dual-carbon targets, mountainous areas are critical ecological barriers with substantial carbon-sink potential. This study investigated the effects of land-use and land-cover change (LUCC) on carbon emission (CE), carbon storage (CS), and carbon balance in Longhui, Dongkou, and Suining counties in the central Xuefeng Mountains. Using LUCC data from 2000 to 2020, we combined the InVEST, PLUS, and Gray Models with an emission-coefficient method to reconstruct historical LUCC and analyze the spatiotemporal patterns of CE and CS. Future carbon balance was then modeled for 2040 under natural development (ND), ecological protection (EP), and economic development (ED) scenarios. The results indicated that: (1) from 2000 to 2020, construction land doubled, whereas cultivated land and forest land decreased significantly; (2) net CE increased by 3.5-fold, with construction land acting as the dominant carbon source and forest land serving as the primary carbon sink. CS declined by 3.7 × 105 t and exhibited a spatial pattern of high in the west, low in the east. The carbon supply-demand ratio (CSDR) showed a continuous downward trend, with central towns approaching carbon deficits. (3) Projections for 2040 indicated that Taohong Town will face a carbon deficit under the ED, while nearing the critical threshold under the ND. Although the EP prevents a deficit, the town remains vulnerable near the tipping point; in contrast, western ecological townships maintain substantial carbon surpluses. Accordingly, four carbon-balance regulation zones are identified, and differentiated governance strategies are proposed. These findings provide a scientific basis for carbon-balance regulation and low-carbon territorial planning in mountainous counties.