| Volumes and Issues Contents of Issue 1 |
www.biogeosciences-discuss.net/6/1657/2009/
doi:10.5194/bgd-6-1657-2009
© Author(s) 2009. This work is distributed
under the Creative Commons Attribution 3.0 License.
Nitrogen fertilization did not affect decay of old lignin and SOC in a 13C-labeled arable soil over 36 years
1Department of Geography, University of Zurich, Zurich, Switzerland
2Institute of Agricultural Chemistry, University of Bologna, Bologna, Italy
3UFZ – Helmholtz Centre for Environmental Research, Leipzig, Germany
Abstract. Retardation of soil organic carbon (SOC) decay after nitrogen addition to litter or soil has been suggested in several recent studies and has been attributed to a retardation in lignin decay. With our study we tested the long-term effect of mineral nitrogen fertilization on the decay of the SOC component lignin in arable soil. To achieve this, we tracked 13C-labeled lignin and SOC in an arable soil that is part of a 36-year field experiment with two mineral nitrogen fertilization levels. We could show that nitrogen fertilization neither retarded nor enhanced the decay of old SOC or lignin over a period of 36 years, proposing that decay of lignin was less sensitive to nitrogen fertilization than previously suggested. However, for fresh biomass there were indications that lignin decay might have been enhanced by nitrogen fertilization, whereas decay of SOC was unaffected. A retardation of SOC decay due to nitrogen addition, as found in other experiments, can therefore only be explained by effects on lignin decay, if lignin was actually measured.
Discussion Paper (PDF, 444 KB) Interactive Discussion (Closed, 3 Comments) Final Revised Paper (BG)
Citation: Hofmann, A., Heim, A., Gioacchini, P., Miltner, A., Gehre, M., and Schmidt, M. W. I.: Nitrogen fertilization did not affect decay of old lignin and SOC in a 13C-labeled arable soil over 36 years, Biogeosciences Discuss., 6, 1657-1675, doi:10.5194/bgd-6-1657-2009, 2009. Bibtex EndNote Reference Manager XML
