The carbon reduction effects of industrial land transition: Intelligently constructed dataset of 16,067 parcels reveals multi-dimensional interactions and nonlinear mechanisms

Industrial land is a frontline for addressing global climate change, yet the carbon effects of its multi-dimensional transitions remain unclear. Taking the Southern Jiangsu Urban Agglomeration in China as a case study, this paper constructs a four-dimensional transition analysis framework of “quantity—spatial—functional—intensity”. The analysis is based on data from 16,067 industrial land parcels (2000–2020), generated through multi-source data and machine learning. Using the two-way fixed effects model and the Geographically and Temporally Weighted Regression (GTWR) model, this study explores the influence mechanism of multi-dimensional transitions of industrial land on carbon emissions. The findings reveal that: (1) The quantity transition of industrial land significantly promotes carbon emissions, while spatial decentralization, functional upgrading, and intensity improvement inhibit carbon emissions; (2) There are interactive synergistic carbon-reducing effects among spatial-functional-intensity transitions, which can offset the carbon-increasing effects of quantity expansion. (3) The impacts of industrial land transition exhibit nonlinearity and heterogeneity. For instance, the impact of intensity transition on emissions follows a “U-shaped” pattern, and the carbon reduction effect of spatial transition exhibits a threshold effect as agglomeration levels increase. This study confirms that the impact of industrial land transition on carbon reduction demonstrates dimensional differences, interactivity, and spatiotemporal dynamics. It provides a synergistic governance pathway of “quantity control—spatial optimization—functional upgrading—intensity threshold regulation” for the low-carbon transition of industrial land in urban agglomerations, offering significant implications for improving the coordination mechanisms between land use and carbon reduction policies.