Effect of antecedent soil moisture conditions on emissions and isotopologue distribution of N2O during denitrification
2011 | journal article. A publication with affiliation to the University of Göttingen.
Jump to: Cite & Linked | Documents & Media | Details | Version history
Cite this publication
Effect of antecedent soil moisture conditions on emissions and isotopologue distribution of N2O during denitrification
Bergstermann, A.; Cardenas, L. M.; Bol, R.; Gilliam, L.; Goulding, K.; Meijide, A. & Scholefield, D. et al. (2011)
Soil Biology and Biochemistry, 43(2) pp. 240-250. DOI: https://doi.org/10.1016/j.soilbio.2010.10.003
Documents & Media
Details
- Authors
- Bergstermann, Anja; Cardenas, Laura M.; Bol, Roland; Gilliam, Lucy; Goulding, Keith; Meijide, Ana; Scholefield, David; Vallejo, Antonio; Well, Reinhard
- Abstract
- The present study determined the influence of initial moisture conditions on the production and consumption of nitrous oxide (N2O) during denitrification and on the isotopic fingerprint of soil-emitted N2O. Sieved arable soil was pre-incubated at two different moisture contents: pre-wet at 75% and pre-dry at 20% water-filled pore space. After wetting to 90% water-filled pore space the soils were amended with glucose (400 kg C ha(-1)) and KNO3 (80 kg N ha(-1)) and incubated for 10 days under a He/O-2-atmosphere. Antecedent moisture conditions affected denitrification. N-2 + N2O fluxes and the N2O-to-N-2 ratio were higher in soils which were pre-incubated under dry conditions, probably because mobilization of organic C during the pre-treatment enhanced denitrification. Gaseous N fluxes showed similar time patterns of production and reduction of N2O in both treatments, where N2O fluxes were initially increasing and maximised 3-4 days after fertilizer application, and N2 fluxes were delayed by 1-2 days. Time courses of delta N-15(bulk)-N2O and delta O-18-N2O exhibited in both treatments increasing trends until maximum N-2 fluxes occurred, reflecting isotope fractionation during intense NO3- reduction. Later this trend slowed down in the pre-dry treatment, while delta O-18-N2O was constant and delta N-15(bulk)-N2O decreased in the pre-wet treatment. We explain these time patterns by non-homogenous distribution of NO3- and denitrification activity, resulting from application of NO3- and glucose to the surface of the soil. We assume that several process zones were thus created, which affected differently the isotopic signature of N2O and the N2O and N-2 fluxes during the different stages of the process. We modelled the delta N-15(bulk)-N2O using process rates and associated fractionation factors for the pre-treated soils, which confirmed our hypothesis. The site preference (SP) initially decreased while N2O reduction was absent, which we could not explain by the N-flux pattern. During the subsequent increase in N-2 flux, SP and delta O-18-N2O increased concurrently, confirming that this isotope pattern is indicative for N2O reduction to N-2. The possible effect of the antecedent moisture conditions of the soil on N2O emissions was shown to be important. (C) 2010 Elsevier Ltd. All rights reserved.
- Issue Date
- 2011
- Status
- published
- Publisher
- Pergamon-elsevier Science Ltd
- Journal
- Soil Biology and Biochemistry
- ISSN
- 0038-0717