Analyzing and predicting the effects of urban spatial planning on the gradient differentiation of production-living-ecological land and carbon storage.

Carbon storage (CS) of terrestrial ecosystems is strongly associated with space utilization changes. However, effects of urban spatial planning on the spatio-temporal heterogeneity of production-living-ecological land (PLEL) and CS remain unclear. To bridge this gap, we developed a new PGIP framework that combines PLEL theory, gradient analysis, the InVEST model, and the PLUS model. This integrated approach offers a comprehensive tool for assessing and simulating how urban planning influences CS. We applied this framework in Jinan, China, where we defined four urban gradient zones to examine the gradient differentiation of PLEL and CS. By integrating dynamic driving factors and urban spatial planning, the PLEL and CS in 2030 were simulated under different scenarios. Results revealed significant gradient-based variations in PLEL between 1980 and 2020. The urban living land (ULL) within 10 km of the city center increased by 117.60%. The CS has decreased by 8.14 × 10⁶ t, and the spatial heterogeneity of CS in the southeastern gradient zone was the strongest. More than 50% of the rise in CS resulted from the shift of rural living land to cultivated production land (CPL), while over 41% of the decrease in CS was caused by the conversion of CPL to ULL. By 2030, urban spatial planning is projected to significantly affect CS pattern, especially in downtown, far suburban, and southeastern gradient zone. Compared with unconstrained development scenario, under spatial planning-guided scenario, high-value clusters of CS will increase by 14.86 km