Impacts of urban growth on vegetation carbon sequestration - Urban Remote Sensing: Monitoring, Synthesis and Modeling in the Urban Environment - page 261

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Impacts of urban growth on vegetation
carbon sequestration
Tingting Zhao
The last two centuries saw increasing human impacts on the global carbon cycle through land-cover/land-use
conversions and the burning of fossil fuels, both highly associated with urban development. The accounting of
urban carbon balance that considers both vegetation carbon sinks and human energy uses, however, remains largely
incomplete at regional to global scales. One of the challenges facing the scientific community involves availability of
data on carbon exchange between vegetation and the atmosphere at large geographic scales. Light-use efficiency
(LUE) models provide a partial solution to this problem through integration of moderate- to coarse-resolution
remote sensing imagery with the measured or modeled vegetation biophysical parameters. In this chapter, the LUE
approach is briefly reviewed and applied to the estimation of gross primary production (GPP) in eight states and
the District of Columbia in the eastern United States in 1992 and 2001. The estimated GPP was associated with
four settlement densities identified based on Census 1990 and 2000 housing unit data. The LUE-based vegetation
productivity estimates may be integrated with carbon emissions data prepared based on energy and transportation
surveys, so as to provide a comprehensive view of net carbon exchange between land and the atmosphere owing to
human urban development.