Diurnal fluxes of CO2 and N2O from cattle-impacted soil and implications for emission estimates

Abstract

Short-term diurnal changes in emissions of CO₂ and N₂O were determined in a cattle overwintering area during three specific periods of the year. Production of both N₂O and CO₂, as determined with gas chambers buried in soil and spatially distributed changed rapidly, and the general course of fluxes of the two gases was different. CO₂emissions were basically controlled by temperature, and most gas chambers showed the same trends in CO₂ flux, indicating low spatial heterogeneity. In contrast, N₂O emissions were much more spatially heterogeneous and each chamber had its own time course of emission; therefore, the relationship between flux and temperature was more complicated for N₂O than CO₂. For estimating gas emissions over long periods, we strongly recommend the use of frequent emission measurements during periods of high gas fluxes.