Analyzing the spatio-temporal carbon change mechanism -- A land-based carbon flow network (CFN) for cities

Abstract High carbon emissions played significant role in global climate change, which made cities with rapid urbanization responsible for local carbon mitigation. In this study, a land-based CFN framework was established by taking 15 land use types as different network nodes. It engaged in exploring the spatio-temporal patterns of the carbon change from a land use perspective, which was followed by the analysis of network utilities to reveal the complex carbon change mechanism. By taking Guangzhou city as an empirical study, the established framework was tested, which showed that the high-level carbon emission patches were found extended from the city center to the city limits with diminished size from 2000 to 2015. Transitions that increased/reduced carbon emissions were detected and revealed the different carbon change mechanism in three time-spans. Exploitation was found significantly contributed to the carbon emissions in 2000–2005 and fell over time. In the built-up area, the dominant carbon relationship has changed from exploitation to mutualism with enlarged carbon emissions. Competition was found continuously increased throughout the study period with favorable mutual restriction effects on carbon emissions, which provided valuable insight for the carbon mitigation through urban planning.