Spatiotemporal Evolution of Carbon Storage in the Central Yunnan Urban Agglomeration and Its Response to LULC Change

[Objective] This paper aims to deepen the understanding of the carbon cycle by analyzing the spatiotemporal evolution characteristics of carbon storage in the central Yunnan urban agglomeration and its response to land use/land cover (LULC) change, so as to effective guidance for carbon management and ecological restoration strategies. [Methods] InVEST and PLUS models were used to simulate and predict the spatiotemporal evolution patterns of carbon storage in the central Yunnan urban agglomeration from 1990 to 2030. By combining data on LULC change, the relationship between carbon storage and LULC change was quantitatively analyzed. [Results] (1) From 1990 to 2020, the land types of the central Yunnan urban agglomeration were mainly forestland, cropland, and grassland, and forestland, cropland, and construction land showed an increasing trend, among which construction land increased the largest. (2) Carbon storage in the central Yunnan urban agglomeration presented a change characteristics of “first increase and then decrease, gradually stabilize”, reaching a maximum value of 1.46×109 t in 2000, and decreasing to 1.45×109 t in 2020, showing a spatial distribution characteristic of “higher in the west, lower in the east”. (3) The carbon storage predictions under different future development scenarios indicated that, compared with 2020, all four scenarios showed a declining trend in carbon storage by 2030, among which the ecological development scenario experienced the least decline, with a reduction of 0.43×107 t compared with 2020, while the cropland development scenario exhibited the most significant decline, with a reduction of 1.05×107 t compared with 2020. (4) The conversion between cultivated land and forestland was the primary factor affecting carbon storage. Specifically, the transformation of cultivated land into forests plays a crucial role in increasing carbon storage in the central Yunnan urban agglomeration. Forest expansion significantly enhanced regional carbon storage, while a reduction in grassland negatively impacted carbon storage. [Conclusion] The conversion of forestland and cultivated land has a significant impact on increasing or decreasing carbon storage in the central Yunnan urban agglomeration.