Date of this Version
Jarecke, K.M., T.D. Loecke, and A.J. Burgin. Coupling soil oxygen and greenhouse gas dynamics. (in prep)
Dynamic soil hydrology triggers important shifts in soil biogeochemical and physical processes that control greenhouse gas (GHG) emissions. Soil oxygen (O2), a direct control on biogenic GHG production (e.g. nitrous oxide-N2O, carbon dioxide-CO2 and methane-CH4), may serve as both an important proxy for determining sudden shifts in subsurface biogenic GHG production as well as the physical transport of soil GHG to the atmosphere. Recent technological advancements offer opportunities to link in-situ, near-continuous measurements of soil O2 concentration to soil biogeochemical processes and soil gas transport. Using high frequency data, this study asked: Do soil O2 dynamics correspond to soil GHG concentration and GHG surface flux? Change in subsurface CO2 and N2O concentrations were inversely related to short-term (< 48 hrs) change in soil O2 concentration at 10 and 20 cm whereas CH4 concentrations did not change in response to soil O2 dynamics. Although soil O2 dynamics at 10 cm did not correspond with change in surface N2O and CH4 flux, change soil O2 concentration at 10 cm had a significant positive linear relationship with change in surface CO2 flux. Our study suggests that coupling near-continuous soil O2 concentration and soil gas flux under dynamic soil hydrology may lead to greater understanding of climate change feedbacks and serve as a relevant predictive tool for future climate change mitigation.
Advisers: Amy J. Burgin and Terrence D. Loecke