Impact of Urban sprawl on carbon uptake in Beijing metropolitan area

Increasing populations and economics intensify the urban growth and cropland encroachment in Beijing metropolitan area. In this paper we investigated the effects of recent urban sprawl (1991-2001) in Beijing metropolitan region, People's Republic of China on ecosystem net primary production (NPP). The analysis employed a mechanistic model of NPP in combination with satellite-derived and ecological data. Our analysis shows that urban growth in the 10-year study period significantly altered the urban ecosystem component of the regional carbon cycle. The annual amount of atmospheric carbon assimilated into phytomass through NPP was reduced by approximately 50.71×10⁴ Mg C (-15.08%). More than half of this reduction is attributed to the loss of cultivated land. Vegetation removal and road disturbance by the expansion of urban areas reduced the amount of carbon uptake.