Abstract
Measuring the stable isotope composition of nitrous oxide (N2O) evolved from soil could improve our understanding of the relative contributions of the main microbial processes (nitrification and denitrification) responsible for N2O formation in soil. However, interpretation of the isotopic data in N2O is complicated by the lack of knowledge of fractionation parameters by different microbial processes responsible for N2O production and consumption. Here we report isotopic enrichment for both nitrogen and oxygen isotopes in two stages of denitrification, N2O production and N2O reduction. We found that during both N2O production and reduction, enrichments were higher for oxygen than nitrogen. For both elements, enrichments were larger for N2O production stage than for N2O reduction. During gross N2O production, the ratio of δ18 O-to-δ15N differed between soils, ranging from 1.6 to 2.7. By contrast, during N2O reduction, we observed a constant ratio of δ18 O-to-δ15N with a value near 2.5. If general, this ratio could be used to estimate the proportion of N2O being reduced in the soil before escaping into the atmosphere. Because N2O-reductase enriches N2O in both isotopes, the global reduction of N2O consumption by soil may contribute to the globally observed isotopic depletion of atmospheric N 2O.
| Original language | English (US) |
|---|---|
| Article number | GB3025 |
| Journal | Global Biogeochemical Cycles |
| Volume | 20 |
| Issue number | 3 |
| DOIs | |
| State | Published - Sep 2006 |
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ASJC Scopus subject areas
- Global and Planetary Change
- Atmospheric Science
- Environmental Science(all)
- Environmental Chemistry
Cite this
Stable isotope discrimination during soil denitrification : Production and consumption of nitrous oxide. / Menyailo, Oleg V.; Hungate, Bruce A.
In: Global Biogeochemical Cycles, Vol. 20, No. 3, GB3025, 09.2006.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Stable isotope discrimination during soil denitrification
T2 - Production and consumption of nitrous oxide
AU - Menyailo, Oleg V.
AU - Hungate, Bruce A
PY - 2006/9
Y1 - 2006/9
N2 - Measuring the stable isotope composition of nitrous oxide (N2O) evolved from soil could improve our understanding of the relative contributions of the main microbial processes (nitrification and denitrification) responsible for N2O formation in soil. However, interpretation of the isotopic data in N2O is complicated by the lack of knowledge of fractionation parameters by different microbial processes responsible for N2O production and consumption. Here we report isotopic enrichment for both nitrogen and oxygen isotopes in two stages of denitrification, N2O production and N2O reduction. We found that during both N2O production and reduction, enrichments were higher for oxygen than nitrogen. For both elements, enrichments were larger for N2O production stage than for N2O reduction. During gross N2O production, the ratio of δ18 O-to-δ15N differed between soils, ranging from 1.6 to 2.7. By contrast, during N2O reduction, we observed a constant ratio of δ18 O-to-δ15N with a value near 2.5. If general, this ratio could be used to estimate the proportion of N2O being reduced in the soil before escaping into the atmosphere. Because N2O-reductase enriches N2O in both isotopes, the global reduction of N2O consumption by soil may contribute to the globally observed isotopic depletion of atmospheric N 2O.
AB - Measuring the stable isotope composition of nitrous oxide (N2O) evolved from soil could improve our understanding of the relative contributions of the main microbial processes (nitrification and denitrification) responsible for N2O formation in soil. However, interpretation of the isotopic data in N2O is complicated by the lack of knowledge of fractionation parameters by different microbial processes responsible for N2O production and consumption. Here we report isotopic enrichment for both nitrogen and oxygen isotopes in two stages of denitrification, N2O production and N2O reduction. We found that during both N2O production and reduction, enrichments were higher for oxygen than nitrogen. For both elements, enrichments were larger for N2O production stage than for N2O reduction. During gross N2O production, the ratio of δ18 O-to-δ15N differed between soils, ranging from 1.6 to 2.7. By contrast, during N2O reduction, we observed a constant ratio of δ18 O-to-δ15N with a value near 2.5. If general, this ratio could be used to estimate the proportion of N2O being reduced in the soil before escaping into the atmosphere. Because N2O-reductase enriches N2O in both isotopes, the global reduction of N2O consumption by soil may contribute to the globally observed isotopic depletion of atmospheric N 2O.
UR - http://www.scopus.com/inward/record.url?scp=34248525409&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34248525409&partnerID=8YFLogxK
U2 - 10.1029/2005GB002527
DO - 10.1029/2005GB002527
M3 - Article
AN - SCOPUS:34248525409
VL - 20
JO - Global Biogeochemical Cycles
JF - Global Biogeochemical Cycles
SN - 0886-6236
IS - 3
M1 - GB3025
ER -