Asking the pikas politely…
The chemical transformations and transport that control nitrogen remains uncharacterized in shale bedrock. Shales may act as a potential hotspot for denitrification due to an abundance of electron donors such as organic matter and sulfide minerals; however, there is uncertainty in the denitrification process in shales. A mechanistic understanding of shale denitrification, which produces gaseous N2 and N2O, is vital to (1) characterizing the global nitrogen budget; and (2) predicting greenhouse gas fluxes from bedrock and their response to environmental change To address this critical knowledge gap, we propose to study the conditions that control and promote N2 and N2O production within the Mancos shale in the East River watershed, CO through combined field monitoring of subsurface environments and laboratory incubation experiments. In this study, we will specifically seek to characterize the magnitude of denitrification rates from the Mancos shale in response to chemical amendments across the watershed and how it varies in response to changes in moisture conditions, oxygen concentrations, and mineralogical availability of electron donors. Our results will quantify denitrification rates and greenhouse gas fluxes from shale bedrock environments. In addition, to providing fundamental insights into a relatively uninterrogated process and its potential effects on shales.