Apportionment of nitrous oxide flux from a successionalMidwest grassland to denitrification and nitrification based onisotopomers

Ostrom, N.E., R.L. Sutka, A.S. Grandy, K.H. Huizinga, P.H. Ostrom, and G.P. Robertson.

Presented at the All Scientist Poster Reception (2006-05-09 )

Apportioning the origins of nitrous oxide to the microbial activity of nitrifyinig and denitrifying bacteria in soils has been an elusive but important aspect of mitigating the fluxes of this important greenhouse gas from soils. Traditional stable isotope approaches have not been successful. In this study, we introduce a new isotopic approach for determining the relative importance of nitrification and denitrification in nitrous oxide flux by measuring the ¹⁵N content in each of the individual atoms in nitrous oxide. The difference ind¹⁵N between these atoms is termed Site Preference (S.P.) and is a promising approach for resolving the origins of nitrous oxide.