Theses and Dissertations Collection

Fire is one of the most influential disturbance agents in the Earth's terrestrial and atmospheric environments; it alters availability of nutrients for plants and directly contributes to the concentration of trace gases and particulates in the atmosphere. Global climate change, coupled with increasing use of prescribed fire, provides an ongoing need for monitoring emission fluxes of trace gases to the atmosphere. As plant communities shift due to changing temperatures and fire frequency (e.g., the cheatgrass-sagebrush systems in the Great Basin, United States), increased knowledge of the variability in timing and quantity of fire emissions is necessary. The research within this thesis is focused on characterizing the uncertainty associated with the calculation of emission flux from shrub-steppe ecosystems. Specifically, this research 1) quantifies the uncertainty within the most widely applied burned area mapping product that is used in United States shrub-steppe ecosystems, 2) characterizes season variability in nitrogenous and carbonaceous trace gas emissions for shrub-steppe systems observed from laboratory burns, and finally 3) discusses possible underlying mechanisms for these observed results.