HR: 14:10h
AN: B33F-03    [Abstracts]
TI: Examining the Role of Nitrogen Cycling in the Terrestrial Response to CO2, Climate, and Nitrogen Deposition
AU: * Yang, X
EM: xyang5@uiuc.edu
AF: University of Illinois, 105 S Gregory St., Urbana, IL 61801, United States
AU: Jain, A
EM: Jain@atmos.uiuc.edu
AF: University of Illinois, 105 S Gregory St., Urbana, IL 61801, United States
AU: Post, W
EM: wmp@ornl.gov
AF: Oak Ridge National Lab, P.O. Box 2008, Oak Ridge, TN 37831, United States
AB: Assessment of simulations to date with coupled carbon cycle-climate models show that carbon cycle feedbacks to climate change could significantly alter the rate of atmospheric CO2 concentration increase and climate change over the century. However, the terrestrial carbon cycle is not only directly altered by increasing atmospheric CO2 and climate change; it is also indirectly altered by feedbacks from nitrogen(N) cycle perturbations induced by changes in CO2 concentration, climate and N deposition. A process-based terrestrial nitrogen cycle model has been developed and coupled with the terrestrial carbon cycle component of Integrated Science Assessment Model (ISAM) to study terrestrial carbon cycle and nitrogen cycle in an integrated way. The coupled carbon-nitrogen model has been applied to a series of modeling experiments examining the influence of nitrogen cycling on the response of the terrestrial biosphere to elevated CO2, climate change, and nitrogen deposition. The results show that the interactions between carbon and nitrogen cycles greatly influence the sensitivity of terrestrial biosphere to the increase of CO2, temperature, precipitation and N deposition leads to an important carbon sink in the coming decades. This model accounts for all the major nitrogen processes such as immobilization, mineralization, nitrification, denitrification, leaching and can be used to estimate nitrogen gas emissions. This talk will focus on describing the results of a series of modeling experiments examining the influence of nitrogen cycling on the response of the terrestrial biosphere to elevated CO2, climate change, and nitrogen deposition.
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0414 Biogeochemical cycles, processes, and modeling (0412, 0793, 1615, 4805, 4912)
DE: 0426 Biosphere/atmosphere interactions (0315)
DE: 0469 Nitrogen cycling
SC: Biogeosciences [B]
MN: 2007 Fall Meeting