Titelangaben
Schnecker, Jörg ; Schindlbacher, Andreas ; Borken, Werner ; Wanek, Wolfgang:
Little effects on soil organic matter chemistry of density fractions after seven years of forest soil warming.
In: Soil Biology & Biochemistry.
Bd. 103
(2016)
.
- S. 300-307.
ISSN 0038-0717
DOI: https://doi.org/10.1016/j.soilbio.2016.09.003
Abstract
Rising temperatures enhance microbial decomposition of soil organic matter (SOM) and thereby increase the soil CO2 efflux. Elevated decomposition rates might differently affect distinct SOM pools, depending on their stability and accessibility. Soil fractions derived from density fractionation have been suggested to represent SOM pools with different turnover times and stability against microbial decomposition.To investigate the effect of soil warming on functionally different soil organic matter pools, we hereinvestigated the chemical and isotopic composition of bulk soil and three density fractions (free particulate organic matter, fPOM; occluded particulate organic matter, oPOM; and mineral associated organic matter, MaOM) of a C-rich soil from a long-term warming experiment in a spruce forest in the Austrian Alps. At the time of sampling, the soil in this experiment had been warmed during the snowfree period for seven consecutive years. During that time no thermal adaptation of the microbial community could be identified and CO2 release from the soil continued to be elevated by the warming treatment. Our results, which included organic carbon content, total nitrogen content, δ13C, Δ14C, δ15N and the chemical composition, identified by pyrolysis-GC/MS, showed no significant differences in bulksoil between warming treatment and control. Surprisingly, the differences in the three density fractions were mostly small and the direction of warming induced change was variable with fraction and soil depth. Warming led to reduced N content in topsoil oPOM and subsoil fPOM and to reduced relative abundance of N-bearing compounds in subsoil MaOM. Further, warming increased the δ13C of MaOM at both sampling depths, reduced the relative abundance of carbohydrates while it increased the relative abundance of lignins in subsoil oPOM. As the size of the functionally different SOM pools did not significantly change, we assume that the few and small modifications in SOM chemistry result from an interplay of enhanced microbial decomposition of SOM and increased root litter input in the warmed plots. Overall, stable functional SOM pool sizes indicate that soil warming had similarly affected easily decomposable and stabilized SOM of this C-rich forest soil.
Weitere Angaben
Publikationsform: | Artikel in einer Zeitschrift |
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Begutachteter Beitrag: | Ja |
Zusätzliche Informationen: | BAYCEER137672 |
Keywords: | Warming; Climate change; Density fractionation; Organic matter chemistry |
Institutionen der Universität: | Forschungseinrichtungen Forschungseinrichtungen > Zentrale wissenschaftliche Einrichtungen Forschungseinrichtungen > Zentrale wissenschaftliche Einrichtungen > Bayreuther Zentrum für Ökologie und Umweltforschung - BayCEER Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Geowissenschaften > Lehrstuhl Bodenökologie Fakultäten Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften Fakultäten > Fakultät für Biologie, Chemie und Geowissenschaften > Fachgruppe Geowissenschaften |
Titel an der UBT entstanden: | Ja |
Themengebiete aus DDC: | 500 Naturwissenschaften und Mathematik |
Eingestellt am: | 18 Jan 2018 13:54 |
Letzte Änderung: | 18 Jun 2024 06:58 |
URI: | https://eref.uni-bayreuth.de/id/eprint/41403 |