Pouyat, Richard (USDA-FS, Northeastern Research Station, c/o Baltimore Ecosystem Study, 5200 Westland Blvd., Baltimore, MD, 21227; Phone: 410-455-8014; Fax: 410-455-8025; Email: rpouyat@fs.fed.us)
R. Pouyat *, I.D. Yesilonis, P.M. Groffman, J. Russell-Anelli
Urban land-use change can potentially affect biogeochemical
cycles through altered disturbance regimes, landscape management practices,
built structures, and changes in environmental factors. These changes have created novel ecosystems,
which have the potential to significantly affect carbon pools and fluxes. For urban ecosystems, very little data
exists to assess whether urbanization leads to an increase or decrease in soil
organic carbon (SOC) pools. We update
previously presented data from research in Baltimore and data mined from the
literature to calculate SOC changes due to urban land-use change. For a 1000 ha hypothetical urban landscape
in the mid-Atlantic region, we estimate a loss of 5 kg C x 10-6 if
the native landscape was previously dominated by hardwood deciduous
forest. In contrast, we estimate a gain
of approximately 4 kg C x
10-6 if the native landscape was predominately a desert ecosystem. These data suggest that the net change in SOC due to urban land-use change will depend on the native ecosystem replaced. For those soils with low initial SOC densities, there is potential to increase C sequestration through management. However, specific urban related management techniques and the effect of site history need to be evaluated.