Cite as:
Castellano-Hinojosa, A.; Loick, N.; Dixon, E.; Matthews, G.P.; Lewicka-Szczebak, D.; Well, R.; Bol, R.; Charteris, A. &amp; Cardenas, L. (2018): <b>Improved isotopic model based on 15N tracing and Rayleigh-type isotope fractionation for simulating differential sources of N2O emissions in a clay grassland soil</b>. <i>Rapid Communications in Mass Spectrometry</i> <b>33</b>, 449-460<br>DOI: <a href="" target="_blank"></a>.

Resource Description

Title: Improved isotopic model based on 15N tracing and Rayleigh-type isotope fractionation for simulating differential sources of N2O emissions in a clay grassland soil
FOR816dw ID: 11
Publication Date: 2018-12-18
License and Usage Rights: DASIM data user agreement. (
Resource Owner(s):
Individual: Antonio Castellano-Hinojosa
Individual: Nadine Loick
Individual: Elisabeth Dixon
Individual: G. Peter Matthews
Individual: Dominika Lewicka-Szczebak
Individual: Reinhard Well
Individual: Roland Bol
Individual: Alice Charteris
Individual: Laura Cardenas
RATIONALE<br/> Isotopic signatures of N2O can help distinguish between two sources (fertiliser N, or endogenous soil N) of N2O emissions. The contribution of each source to N2O emissions after N–application is difficult to determine. Here, isotopologue signatures of emitted N2O are used in an improved isotopic model based on Rayleigh type equations.<br/> <br/> METHODS<br/> The effects of a partial (33% of surface area, treatment 1c) or total (100% of surface area, treatment 3c) dispersal of N and C on gaseous emissions from denitrification were measured in a laboratory incubation system (DENIS) allowing simultaneous measurements of NO, N2O, N2 and CO2 over a 12?day incubation period. To determine the source of N2O emissions those results were combined with both the isotope ratio mass spectrometry analysis of the isotopocules of emitted N2O and the 15N?tracing technique.<br/> <br/> RESULTS<br/> The spatial dispersal of N and C significantly affected the quantity, but not the timing of gas fluxes. Cumulative emissions are larger for 3c than 1c. The 15N?enrichment analysis shows that initially ~70% of the emitted N2O derived from the applied amendment followed by a constant decrease. The decrease in contribution of the fertiliser N?pool after an initial increase is sooner and larger for 1c. The Rayleigh type model applied to N2O isotopocules data (?15Nbulk?N2O values) shows poor agreement with the measurements for the original 1?pool model for 1c; the 2?pool models gives better results when using a third order polynomial equation. In contrast, in 3c little difference is observed between the two modelling approaches.<br/> <br/> CONCLUSIONS<br/> The importance of N2O emissions from different N?pools in soil for the interpretation of N2O isotopocules data was demonstrated using a Rayleigh type model. Earlier statements concerning exponential increase of native soil nitrate pool activity highlighted in previous studies should be replaced with a polynomial increase with dependency on both N?pool sizes.
| denitrification | greenhouse gas | isotopes | isotopocules | Rayleigh type model |
Literature type specific fields:
Journal: Rapid Communications in Mass Spectrometry
Volume: 33
Page Range: 449-460
Metadata Provider:
Individual: Kristina Kleineidam
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