Analyzing spatial patterns of urban carbon metabolism: A case study in Beijing, China

Abstract

Analyzing the spatial pattern of a city's carbon metabolism can provide insights into the spatial adjustments required to mitigate the greenhouse effect. Using GIS software and empirical coefficients, we analyzed the spatial distribution of Beijing's carbon metabolism in 5 years (1990, 1995, 2000, 2005, and 2008), and analyzed both temporal and spatial changes in this pattern. Our results highlight the importance of the expansion of built-up areas in defining the patterns of Beijing's carbon metabolism, and let us explore options for changing these patterns. Carbon emission was high in the highly urbanized southeastern parts of the city and low in the less-urbanized northwestern parts, whereas carbon sequestration showed the opposite pattern (low in southeastern parts and high in northwestern parts). During the study period, carbon sequestration only offset 2.4% of carbon emission, indicating a serious imbalance of the city's carbon metabolism. The city's core built-up area expanded along eight axes, and its form fluctuated between simpler and more complex. From a small-scale perspective, the spatial pattern mainly showed expansion and aggregation of patches with high carbon emission and shrinkage and fragmentation of patches with high carbon sequestration. These results provide insights that will guide the development of more effective management of the spatial patterns of carbon emission and sequestration.