A recent paper presents new insights into the relationship between soil CO2 fluxes and soil moisture

Tuesday, May 9, 2023

Figure showing relationship between soil CO2 fluxes and soil moisture

 Conceptual representation of the relationship between soil CO2 efflux and soil moisture modified from Moyano et al. (2013).

A new paper published in the journal Geoderma demonstrates the major role of anaerobic mineralization in explaining high CO2 fluxes when soil moisture approaches full saturation. The paper is co-authored by Linden Fairbairn, Fereidoun Rezanezhad, Mehdi Gharasoo, Chris Parsons, Stephanie Slowinski, Philippe Van Cappellen from the Ecohydrology Research Group and Merrin Macrae from the Department of Geography and Environmental Management at Waterloo. In this study, soil incubations with variable soil moisture content were carried out, and gas (CO2 and CH4) fluxes and porewater geochemistry were monitored. A kinetic model representing both aerobic and anaerobic CO2 production captured the observed gas fluxes. Overall, we concluded that existing soil respiration models may underrepresent soil CO2 production under (near) water-saturated conditions.

The paper can be accessed at:https://www.sciencedirect.com/science/article/pii/S0016706123001702?via%3Dihub