Multi-scenario optimization of land use and net carbon effects under China's dual-carbon goals: Evidence from Hubei Province, China

The disorderly expansion of construction land is encroaching upon ecological carbon sink spaces at an unprecedented rate, transforming the land-use system from a carbon balancer into a key driver of regional carbon budget imbalance. In response to the lack of a unified analytical framework integrating the carbon sequestration of non-construction land, carbon emissions from construction land, and land-based economic benefits at the provincial scale, this study takes Hubei Province as the research area and develops a net carbon effect assessment framework encompassing these three dimensions. Linear trend projection, multi-objective programming (MOP), and the GeoSOS-FLUS model were jointly employed to establish four scenarios, namely BAU, EDP, LDS, and EEB, and to simulate land-use allocation and associated net carbon effects in 2030 and 2060. The results indicate that from 2000 to 2020, land-use change in Hubei Province was characterized by the contraction of agricultural space, the expansion of construction space, and the relative stability of the ecological substrate. The spatial pattern of net carbon effects exhibited a clear structure of “carbon sinks in the west and north, and carbon sources in the east and south.” Multi-scenario comparisons further reveal that the EEB scenario provides a representative economic–carbon compromise under equal weights assigned to normalized economic and carbon objectives, subject to ecological and development constraints. These findings provide decision-making support with both planning guidance and policy interpretability for provincial territorial spatial optimization and low-carbon transition under China's dual-carbon goals.