Research on the space-time evolution of carbon storage in Yunnan Province, China and its driving mechanism from the perspective of slope

Motivated by the effects of global warming, investigating how land use changes may affect carbon storage (CS) is essential. Using Yunnan Province, a typical highland hilly region in China, as an example, this study examined the factors causing the spatiotemporal heterogeneity of CS from a slope viewpoint, and mimicked how land use patterns and CS will alter in the scenarios of Natural Change (NCS), Ecological Protection (EPS) and Prevention of Urban Expansion (PUES) in 2030 coupling the PLUS-InVEST-OPGD-GTWR. The results show: (1) Overall CS declined from 2000 to 2020, with elevated values in isolated mountainous regions of the west and north and low values in the densely populated areas of the east and south. (2) The slope and population density are decisive for the spatial heterogeneity of CS. (3) The slope is the primary determinant of CS, in which the CS of cropland, grassland, waters, and unused land is dominantly distributed in the area with a slope of 5–15°, while the CS of woodland and construction land is primarily found in the region with 15–25° and 25–35° slope, respectively. (4) The CS under NCS, EPS, and PUES are expected to change by −0.5 × 103 t, 0.9973 × 106 t, and 0.5692 × 106 t, respectively, compared with 2020. This study presents a reference for the global highland hilly regions, such as Yunnan Province, to achieve ecological protection and sustainable development.