TY  - JOUR
AU  - Wei, Jing
AU  - Ibraim, Erkan
AU  - Brüggemann, Nicolas
AU  - Vereecken, Harry
AU  - Mohn, Joachim
TI  - First real-time isotopic characterisation of N2O from chemodenitrification
JO  - Geochimica et cosmochimica acta
VL  - 267
SN  - 0016-7037
CY  - New York, NY [u.a.]
PB  - Elsevier
M1  - FZJ-2019-05563
SP  - 17-32
PY  - 2019
AB  - Chemodenitrification can be a substantial abiotic source of nitrous oxide (N2O) in soil. The isotopic signature of N2O from this process could support source partitioning, but it is currently unknown in sufficient detail. In this study, we determined the isotopic composition of N2O, produced by the reaction of nitrite (NO2−) with lignin, four lignin derivatives, and three types of soils, online with a quantum cascade laser absorption spectrometer (QCLAS). We present the first dataset of continuous measurements of δ15Nbulk (δ15Nbulk ≡ (δ15Nα + δ15Nβ)/2), δ18O, and site preference (SPN2O, SPN2O ≡ δ15Nα − δ15Nβ) of N2O from chemodenitrification in both chemical assays and soils. Considerable amounts of N2O were produced by chemical reduction of NO2−, indicating that chemodenitrification could dominate N2O emission in NO2−-rich environments. The values of SPN2O varied by more than 20‰ in the reactions of sodium nitrite with organic substances. Contrary to the common assumption that SPN2O values are constant for a distinct N2O source process, our results reveal a considerable shift in SPN2O over time for most experiments. The large SPN2O variability might be explained by the multiple pathways with hyponitrous acid or nitramide as N2O precursors. These findings provide important new information to improve our understanding about the dependency of N2O isotopic signatures on N2O production processes.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000491872600002
DO  - DOI:10.1016/j.gca.2019.09.018
UR  - https://juser.fz-juelich.de/record/866410
ER  -