Examining spatial carbon metabolism: Features, future simulation, and land-based mitigation

A comprehensive understanding of the spatial carbon metabolism distribution is essential for future mitigation policies from a land-based perspective. This study develops a methodological framework for carbon metabolism measurement and future simulation. An assessment of carbon sequestration and emission is conducted based on land use components within the biosphere. Carbon scenarios in accordance with the governmental mitigation policy were then established, and these were coupled with future multiple-type land use transitions to simulate the future spatial carbon distribution. This future carbon distribution map can help us understand the carbon dynamics in specific locations with possible land-based mitigation for policy making. Guangzhou, which is a rapid urbanization metropolis in China, was taken as a case study to conduct the proposed methodological framework and models. The results revealed that high-density carbon emissions dominated in the city center and expanded in the east-west direction, while carbon sequestration diminished in the middle and southern areas, with a decreased total sequestration amount. The carbon distribution in the 2030 scenarios highlighted different mitigation implications for different locations in the north, south, and central areas. Projections of emission reductions in northern outskirts and southern sub-center, as well as the projections of sequestration increases in the city center and northern mountainous area are then proposed to support mitigation. The established framework is proven to be effective for examining spatial carbon features at an urban scale, and the empirical findings can provide valuable insight into carbon mitigation strategies for rapid urbanization areas in developing countries.