HR: 1340h
AN: B23C-1507    [Abstracts]
TI: Long-term Soil C and N Dynamics in Response to Enhanced Wind Erosion in Semiarid Grassland, Using CENTURY Model
AU: * Li, J
EM: jl2mc@virginia.edu
AF: Department of Environmental Sciences, University of Virginia, 291 McCormick Road, Charlottesville, VA 22903, United States
AU: Okin, G S
EM: okin@ucla.edu
AF: Department of Geography, University of California, Los Angeles, 1255 Bunche Hall, Los Angeles, CA 90095, United States
AU: Alavrez, L
EM: ljh3x@virginia.edu
AF: Department of Environmental Sciences, University of Virginia, 291 McCormick Road, Charlottesville, VA 22903, United States
AU: Epstein, H
EM: hee2b@virginia.edu
AF: Department of Environmental Sciences, University of Virginia, 291 McCormick Road, Charlottesville, VA 22903, United States
AB: Recent studies show that enhanced wind erosion changes soil carbon (C) and nitrogen (N) cycling in desert grasslands of southern New Mexico. However, long-term effects at the scale of decades to centuries are less known, especially under the conditions of drought, directional changes in climate, and land use pressures. Additionally, previous studies have focused on the isolated response of soil C and N, with little understanding of their interactions and differential response of other sub-pools. Using CENTURY, a process-based biogeochemical model, we evaluate the potential impacts of enhanced wind erosion on the long-term dynamics of C and N in the Jornada Experimental Range, southern New Mexico. We find that enhanced wind erosion does have a significant effect on long-term dynamics of C and N that are similar to the short-term dynamics observed in a field experiment at Jornada. The relationships between pools of C and N, levels of wind erosion and vegetation cover reduction as well as the mechanisms by which wind erosion changes C and N cycling in desert grasslands are discussed.
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 0470 Nutrients and nutrient cycling (4845, 4850)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting