Biogeochemistry, 2017, Vol.132(3), pp.325-342
To access, purchase, authenticate, or subscribe to the full-text of this article, please visit this link: http://dx.doi.org/10.1007/s10533-017-0306-0 Byline: Jing Wei (1), Wulf Amelung (1,2), Eva Lehndorff (2), Michael Schloter (3), Harry Vereecken (1), Nicolas Bruggemann (1) Keywords: NO.sub.2 .sup.-; Nitrous oxide; Soil organic matter; Nitric oxide; Site preference Abstract: Abstract Nitrite (NO.sub.2 .sup.-) as an important intermediate of the biological nitrogen cycle is particularly reactive in acidic soils and acts as a source of [N.sub.2]O and NO.sub.x (NO and NO.sub.2). However, abiotic and biotic pathways of NO.sub.2 .sup.--driven [N.sub.2]O and NO.sub.x production in forest soil and the role of soil organic matter (SOM) in these processes are still unclear. In this study, NO.sub.2 .sup.- was applied to both unsterile and sterilized soil samples as well as to different SOM fractions from a Norway spruce forest. Biotic and abiotic [N.sub.2]O emission was measured with an infrared absorption analyzer and gas chromatography, while NO.sub.x emission was quantified with a chemiluminescence analyzer. Isotopic signatures of [N.sub.2]O ([delt[a].sup.15]N.sup.bulk, [delt[a].sup.18]O, and 15.sup.N-[N.sub.2]O site preference) were analyzed with an isotope ratio mass spectrometer. After NO.sub.2 .sup.- addition, a large amount of NO.sub.x was emitted immediately, while [N.sub.2]O emission occurred 15--60 min later and was much lower compared to NO.sub.x. Sterilization of soil decreased [N.sub.2]O emission significantly, but not NO.sub.x emission. The 15.sup.N site preference of [N.sub.2]O ranged from 7.98 to 11.58[per thousand] for abiotic and 4.69--7.42[per thousand] for biotic sources. The fulvic acid fraction contributed the most to abiotic [N.sub.2]O emission, while the fastest NO and [N.sub.2]O emission occurred after NO.sub.2 -.sup.application to the humin fraction, followed by the humic acid fraction. These results are important for the future understanding of NO.sub.x and [N.sub.2]O sources, as well as the use of isotopic signatures for source-partitioning [N.sub.2]O emission from soil. Graphical Abstract Author Affiliation: (1) Forschungszentrum Julich GmbH, Institute of Bio- and Geosciences, Agrosphere (IBG-3), Wilhelm-Johnen-Stra[sz]e, 52425, Julich, Germany (2) Institute of Crop Science and Resource Conservation, Soil Science & Soil Ecology, University of Bonn, Nussallee 13, 53115, Bonn, Germany (3) Research Unit for Environmental Genomics, Helmholtz Zentrum Munchen-Deutsches Forschungszentrum fur Gesundheit und Umwelt (GmbH), Ingolstadter Landstra[sz]e 1, 85764, Neuherberg, Germany Article History: Registration Date: 03/02/2017 Received Date: 21/10/2016 Accepted Date: 03/02/2017 Online Date: 17/02/2017 Article note: Responsible Editor: E. Matzner. Electronic supplementary material The online version of this article (doi: 10.1007/s10533-017-0306-0) contains supplementary material, which is available to authorized users.
NO ; Nitrous oxide ; Soil organic matter ; Nitric oxide ; Site preference
View full text in Springer (Subscribers only)